SLIB is a portable library for the programming language Scheme. It provides a platform independent framework for using packages of Scheme procedures and syntax. As distributed, SLIB contains useful packages for all implementations. Its catalog can be transparently extended to accomodate packages specific to a site, implementation, user, or directory.
Aubrey Jaffer <jaffer@ai.mit.edu>
Hyperactive Software -- The Maniac Inside!
http://www-swiss.ai.mit.edu/~jaffer/SLIB.html
SLIB denotes features by symbols. SLIB maintains a list of features supported by the Scheme session. The set of features provided by a session may change over time. Some features are properties of the Scheme implementation being used. The following features detail what sort of numbers are available from an implementation.
Other features correspond to the presence of sets of Scheme procedures or syntax (macros).
#t if feature is supported by the current Scheme
session.
(provided? feature) will return #t.
(provided? 'foo) => #f (provide 'foo) (provided? 'foo) => #t
SLIB creates and maintains a catalog mapping features to locations of files introducing procedures and syntax denoted by those features.
At the beginning of each section of this manual, there is a line like
(require 'feature).
The Scheme files comprising SLIB are cataloged so that these feature
names map to the corresponding files.
SLIB provides a form, require, which loads the files providing
the requested feature.
(provided? feature) is true,
then require just returns an unspecified value.
(provided? feature) will return #t.
The catalog can also be queried using require:feature->path.
#t.
#f.
At the start of a session no catalog is present, but is created with the
first catalog inquiry (such as (require 'random)). Several
sources of catalog information are combined to produce the catalog:
cd to this directory before starting the
Scheme session.
Catalog files consist of one or more association lists. In the circumstance where a feature symbol appears in more than one list, the latter list's association is retrieved. Here are the supported formats for elements of catalog lists:
(feature . <symbol>)
(feature . "<path>")
(feature source "<path>")
slib:loads the Scheme source file <path>.
(feature compiled "<path>" ...)
slib:load-compileds the files <path> ....
The various macro styles first require the named macro package,
then just load <path> or load-and-macro-expand <path> as
appropriate for the implementation.
(feature defmacro "<path>")
defmacro:loads the Scheme source file <path>.
(feature macro-by-example "<path>")
defmacro:loads the Scheme source file <path>.
(feature macro "<path>")
macro:loads the Scheme source file <path>.
(feature macros-that-work "<path>")
macro:loads the Scheme source file <path>.
(feature syntax-case "<path>")
macro:loads the Scheme source file <path>.
(feature syntactic-closures "<path>")
macro:loads the Scheme source file <path>.
Here is an example of a `usercat' catalog. A Program in this
directory can invoke the `run' feature with (require 'run).
;;; "usercat": SLIB catalog additions for SIMSYNCH. -*-scheme-*- ( (simsynch . "../synch/simsynch.scm") (run . "../synch/run.scm") (schlep . "schlep.scm") )
SLIB combines the catalog information which doesn't vary per user into the file `slibcat' in the implementation-vicinity. Therefore `slibcat' needs change only when new software is installed or compiled. Because the actual pathnames of files can differ from installation to installation, SLIB builds a separate catalog for each implementation it is used with.
The definition of *SLIB-VERSION* in SLIB file `require.scm'
is checked against the catalog association of *SLIB-VERSION* to
ascertain when versions have changed. I recommend that the definition
of *SLIB-VERSION* be changed whenever the library is changed. If
multiple implementations of Scheme use SLIB, remember that recompiling
one `slibcat' will fix only that implementation's catalog.
The compilation scripts of Scheme implementations which work with SLIB
can automatically trigger catalog compilation by deleting
`slibcat' or by invoking a special form of require:
Another special form of require erases SLIB's catalog, forcing it
to be reloaded the next time the catalog is queried.
Each file in the table below is descibed in terms of its file-system independent vicinity (see section Vicinity). The entries of a catalog in the table override those of catalogs above it in the table.
implementation-vicinity `slibcat'
library-vicinity `mklibcat.scm'
library-vicinity `sitecat'
implementation-vicinity `implcat'
implementation-vicinity.
implementation-vicinity `mkimpcat.scm'
implementation-vicinity `sitecat'
home-vicinity `homecat'
user-vicinity `usercat'
user-vicinity.
The procedures described in these sections are supported by all implementations as part of the `*.init' files or by `require.scm'.
required.
*features* must be defined by all implementations
(see section Porting).
Here are features which SLIB (`require.scm') adds to *features* when appropriate.
For each item, (provided? 'feature) will return #t
if that feature is available, and #f if not.
source, or compiled. The cdr of the pathname
should be either a string or a list.
In the following functions if the argument feature is not a symbol it is assumed to be a pathname.
#t if feature is a member of *features* or
*modules* or if feature is supported by a file already
loaded and #f otherwise.
(provided? feature) is true
require returns. Otherwise, if (assq feature
*catalog*) is not #f, the associated files will be loaded and
(provided? feature) will henceforth return #t. An
unspecified value is returned. If feature is not found in
*catalog*, then an error is signaled.
require, pathname is loaded.
An unspecified value is returned.
*features* if
feature is a symbol and *modules* otherwise.
#t if feature is a member of *features* or
*modules* or if feature is supported by a file already
loaded. Returns a path if one was found in *catalog* under the
feature name, and #f otherwise. The path can either be a string
suitable as an argument to load or a pair as described above for
*catalog*.
A vicinity is a descriptor for a place in the file system. Vicinities hide from the programmer the concepts of host, volume, directory, and version. Vicinities express only the concept of a file environment where a file name can be resolved to a file in a system independent manner. Vicinities can even be used on flat file systems (which have no directory structure) by having the vicinity express constraints on the file name. On most systems a vicinity would be a string. All of these procedures are file system dependent.
These procedures are provided by all implementations.
in-vicinity.
program-vicinity can
return incorrect values if your program escapes back into a
load.
home-vicinity
returns #f.
slib:load,
slib:load-source, slib:load-compiled,
open-input-file, open-output-file, etc. The returned
filename is filename in vicinity. in-vicinity should
allow filename to override vicinity when filename is
an absolute pathname and vicinity is equal to the value of
(user-vicinity). The behavior of in-vicinity when
filename is absolute and vicinity is not equal to the value
of (user-vicinity) is unspecified. For most systems
in-vicinity can be string-append.
sub-vicinity will
return a pathname of the subdirectory name of
vicinity.These constants and procedures describe characteristics of the Scheme and underlying operating system. They are provided by all implementations.
char->integer.
unix, vms, macos, amiga, or
ms-dos.
(slib:report-version) => slib "2c0" on scm "5b1" on unix
(slib:report-version) followed by
almost all the information neccessary for submitting a problem report.
An unspecified value is returned.
(slib:report)
=>
slib "2c0" on scm "5b1" on unix
(implementation-vicinity) is "/home/jaffer/scm/"
(library-vicinity) is "/home/jaffer/slib/"
(scheme-file-suffix) is ".scm"
loaded *features* :
trace alist qp sort
common-list-functions macro values getopt
compiled
implementation *features* :
bignum complex real rational
inexact vicinity ed getenv
tmpnam abort transcript with-file
ieee-p1178 rev4-report rev4-optional-procedures hash
object-hash delay eval dynamic-wind
multiarg-apply multiarg/and- logical defmacro
string-port source current-time record
rev3-procedures rev2-procedures sun-dl string-case
array dump char-ready? full-continuation
system
implementation *catalog* :
(i/o-extensions compiled "/home/jaffer/scm/ioext.so")
...
These procedures are provided by all implementations.
#t if the specified file exists. Otherwise, returns
#f. If the underlying implementation does not support this
feature then #f is always returned.
#f is returned. Otherwise, #t is
returned.
(tmpnam) will return different
pathnames.
(current-output-port).
Returns the width of port, which defaults to
(current-output-port) if absent. If the width cannot be
determined 79 is returned.
Returns the height of port, which defaults to
(current-output-port) if absent. If the height cannot be
determined 24 is returned.
These procedures are provided by all implementations.
Example:
(identity 3) => 3 (identity '(foo bar)) => (foo bar) (map identity lst) == (copy-list lst)
The following procedures were present in Scheme until R4RS (see section `Language changes' in Revised(4) Scheme). They are provided by all SLIB implementations.
#t.
#f.
(last-pair (cons 1 2))
=> (1 . 2)
(last-pair '(1 2))
=> (2)
== (cons 2 '())
These procedures are provided by all implementations.
(slib:load-source "foo") will
load from file `foo.scm'.
If an implementation does not support compiled code then
slib:load will be identical to slib:load-source.
eval returns the value of obj evaluated in the current top
level environment.
slib:eval-load procedure does not affect the values returned by
current-input-port and current-output-port.
#t, a success status is returned to the
system (if possible). If n is #f a failure is returned to
the system (if possible). If n is an integer, then n is
returned to the system (if possible). If the Scheme session cannot exit
an unspecified value is returned from slib:exit.
scm Scheme
implementation.
(require 'feature). Include this line in your code prior to
using the package.
Defmacros are supported by all implementations.
(gentemp) => scm:G0 (gentemp) => scm:G1
slib:eval of expanding all defmacros in scheme
expression e.
defmacro:load procedure reads Scheme source code expressions
and definitions from the file and evaluates them sequentially. These
source code expressions and definitions may contain defmacro
definitions. The macro:load procedure does not affect the values
returned by current-input-port and
current-output-port.
#t if sym has been defined by defmacro,
#f otherwise.
macroexpand-1 will expand the
macro call once and return it. A form is considered to be a macro
call only if it is a cons whose car is a symbol for which a
defmacr has been defined.
macroexpand is similar to macroexpand-1, but repeatedly
expands form until it is no longer a macro call.
defmacro:eval, defmacro:macroexpand*,
or defmacro:load defines a new macro which will henceforth be
expanded when encountered by defmacro:eval,
defmacro:macroexpand*, or defmacro:load.
(require 'macro) is the appropriate call if you want R4RS
high-level macros but don't care about the low level implementation. If
an SLIB R4RS macro implementation is already loaded it will be used.
Otherwise, one of the R4RS macros implemetations is loaded.
The SLIB R4RS macro implementations support the following uniform interface:
macro:load procedure reads Scheme source code expressions and
definitions from the file and evaluates them sequentially. These source
code expressions and definitions may contain macro definitions. The
macro:load procedure does not affect the values returned by
current-input-port and current-output-port.
A vanilla implementation of Macro by Example (Eugene Kohlbecker,
R4RS) by Dorai Sitaram, (dorai@cs.rice.edu) using defmacro.
define-syntax Macro-by-Example macros
cheaply.
....
defmacro
natively supported (most implementations)
These macros are not referentially transparent (see section `Macros' in Revised(4) Scheme). Lexically scoped macros (i.e., let-syntax
and letrec-syntax) are not supported. In any case, the problem
of referential transparency gains poignancy only when let-syntax
and letrec-syntax are used. So you will not be courting
large-scale disaster unless you're using system-function names as local
variables with unintuitive bindings that the macro can't use. However,
if you must have the full r4rs macro functionality, look to the
more featureful (but also more expensive) versions of syntax-rules
available in slib section Macros That Work, section Syntactic Closures, and
section Syntax-Case Macros.
syntax-rules.
The top-level syntactic environment is extended by binding the keyword to the specified transformer.
(define-syntax let*
(syntax-rules ()
((let* () body1 body2 ...)
(let () body1 body2 ...))
((let* ((name1 val1) (name2 val2) ...)
body1 body2 ...)
(let ((name1 val1))
(let* (( name2 val2) ...)
body1 body2 ...)))))
(pattern template)
where the pattern and template are as in the grammar above.
An instance of syntax-rules produces a new macro transformer by
specifying a sequence of hygienic rewrite rules. A use of a macro whose
keyword is associated with a transformer specified by
syntax-rules is matched against the patterns contained in the
syntax-rules, beginning with the leftmost syntax-rule.
When a match is found, the macro use is trancribed hygienically
according to the template.
Each pattern begins with the keyword for the macro. This keyword is not involved in the matching and is not considered a pattern variable or literal identifier.
Macros That Work differs from the other R4RS macro implementations in that it does not expand derived expression types to primitive expression types.
macro:eval returns the value of expression in the current
top level environment. expression can contain macro definitions.
Side effects of expression will affect the top level
environment.
macro:load procedure reads Scheme source code expressions and
definitions from the file and evaluates them sequentially. These source
code expressions and definitions may contain macro definitions. The
macro:load procedure does not affect the values returned by
current-input-port and current-output-port.References:
The Revised^4 Report on the Algorithmic Language Scheme Clinger and Rees [editors]. To appear in LISP Pointers. Also available as a technical report from the University of Oregon, MIT AI Lab, and Cornell.
Macros That Work. Clinger and Rees. POPL '91.
The supported syntax differs from the R4RS in that vectors are allowed as patterns and as templates and are not allowed as pattern or template data.
transformer spec ==> (syntax-rules literals rules)
rules ==> ()
| (rule . rules)
rule ==> (pattern template)
pattern ==> pattern_var ; a symbol not in literals
| symbol ; a symbol in literals
| ()
| (pattern . pattern)
| (ellipsis_pattern)
| #(pattern*) ; extends R4RS
| #(pattern* ellipsis_pattern) ; extends R4RS
| pattern_datum
template ==> pattern_var
| symbol
| ()
| (template2 . template2)
| #(template*) ; extends R4RS
| pattern_datum
template2 ==> template
| ellipsis_template
pattern_datum ==> string ; no vector
| character
| boolean
| number
ellipsis_pattern ==> pattern ...
ellipsis_template ==> template ...
pattern_var ==> symbol ; not in literals
literals ==> ()
| (symbol . literals)
...) is
the pattern or template that appears to its left.
No pattern variable appears more than once within a pattern.
For every occurrence of a pattern variable within a template, the template rank of the occurrence must be greater than or equal to the pattern variable's rank.
Every ellipsis template must open at least one variable.
For every ellipsis template, the variables opened by an ellipsis template must all be bound to sequences of the same length.
The compiled form of a rule is
rule ==> (pattern template inserted)
pattern ==> pattern_var
| symbol
| ()
| (pattern . pattern)
| ellipsis_pattern
| #(pattern)
| pattern_datum
template ==> pattern_var
| symbol
| ()
| (template2 . template2)
| #(pattern)
| pattern_datum
template2 ==> template
| ellipsis_template
pattern_datum ==> string
| character
| boolean
| number
pattern_var ==> #(V symbol rank)
ellipsis_pattern ==> #(E pattern pattern_vars)
ellipsis_template ==> #(E template pattern_vars)
inserted ==> ()
| (symbol . inserted)
pattern_vars ==> ()
| (pattern_var . pattern_vars)
rank ==> exact non-negative integer
where V and E are unforgeable values.
The pattern variables associated with an ellipsis pattern are the variables bound by the pattern, and the pattern variables associated with an ellipsis template are the variables opened by the ellipsis template.
If the template contains a big chunk that contains no pattern variables or inserted identifiers, then the big chunk will be copied unnecessarily. That shouldn't matter very often.
macro:eval returns the value of expression in the current
top level environment. expression can contain macro definitions.
Side effects of expression will affect the top level
environment.
macro:load procedure reads Scheme source code expressions and
definitions from the file and evaluates them sequentially. These
source code expressions and definitions may contain macro definitions.
The macro:load procedure does not affect the values returned by
current-input-port and current-output-port.A Syntactic Closures Macro Facility by Chris Hanson 9 November 1991
This document describes syntactic closures, a low-level macro facility for the Scheme programming language. The facility is an alternative to the low-level macro facility described in the Revised^4 Report on Scheme. This document is an addendum to that report.
The syntactic closures facility extends the BNF rule for transformer spec to allow a new keyword that introduces a low-level macro transformer:
transformer spec := (transformer expression)
Additionally, the following procedures are added:
make-syntactic-closure capture-syntactic-environment identifier? identifier=?
The description of the facility is divided into three parts. The first
part defines basic terminology. The second part describes how macro
transformers are defined. The third part describes the use of
identifiers, which extend the syntactic closure mechanism to be
compatible with syntax-rules.
This section defines the concepts and data types used by the syntactic closures facility.
set! special form is also a form. Examples of
forms:
17 #t car (+ x 4) (lambda (x) x) (define pi 3.14159) if define
symbol?. Macro transformers rarely distinguish symbols from
aliases, referring to both as identifiers.
This section describes the transformer special form and the
procedures make-syntactic-closure and
capture-syntactic-environment.
Syntax: It is an error if this syntax occurs except as a transformer spec.
Semantics: The expression is evaluated in the standard transformer
environment to yield a macro transformer as described below. This macro
transformer is bound to a macro keyword by the special form in which the
transformer expression appears (for example,
let-syntax).
A macro transformer is a procedure that takes two arguments, a
form and a syntactic environment, and returns a new form. The first
argument, the input form, is the form in which the macro keyword
occurred. The second argument, the usage environment, is the
syntactic environment in which the input form occurred. The result of
the transformer, the output form, is automatically closed in the
transformer environment, which is the syntactic environment in
which the transformer expression occurred.
For example, here is a definition of a push macro using
syntax-rules:
(define-syntax push
(syntax-rules ()
((push item list)
(set! list (cons item list)))))
Here is an equivalent definition using transformer:
(define-syntax push
(transformer
(lambda (exp env)
(let ((item
(make-syntactic-closure env '() (cadr exp)))
(list
(make-syntactic-closure env '() (caddr exp))))
`(set! ,list (cons ,item ,list))))))
In this example, the identifiers set! and cons are closed
in the transformer environment, and thus will not be affected by the
meanings of those identifiers in the usage environment
env.
Some macros may be non-hygienic by design. For example, the following
defines a loop macro that implicitly binds exit to an escape
procedure. The binding of exit is intended to capture free
references to exit in the body of the loop, so exit must
be left free when the body is closed:
(define-syntax loop
(transformer
(lambda (exp env)
(let ((body (cdr exp)))
`(call-with-current-continuation
(lambda (exit)
(let f ()
,@(map (lambda (exp)
(make-syntactic-closure env '(exit)
exp))
body)
(f))))))))
To assign meanings to the identifiers in a form, use
make-syntactic-closure to close the form in a syntactic
environment.
environment must be a syntactic environment, free-names must
be a list of identifiers, and form must be a form.
make-syntactic-closure constructs and returns a syntactic closure
of form in environment, which can be used anywhere that
form could have been used. All the identifiers used in
form, except those explicitly excepted by free-names, obtain
their meanings from environment.
Here is an example where free-names is something other than the
empty list. It is instructive to compare the use of free-names in
this example with its use in the loop example above: the examples
are similar except for the source of the identifier being left
free.
(define-syntax let1
(transformer
(lambda (exp env)
(let ((id (cadr exp))
(init (caddr exp))
(exp (cadddr exp)))
`((lambda (,id)
,(make-syntactic-closure env (list id) exp))
,(make-syntactic-closure env '() init))))))
let1 is a simplified version of let that only binds a
single identifier, and whose body consists of a single expression. When
the body expression is syntactically closed in its original syntactic
environment, the identifier that is to be bound by let1 must be
left free, so that it can be properly captured by the lambda in
the output form.
To obtain a syntactic environment other than the usage environment, use
capture-syntactic-environment.
capture-syntactic-environment returns a form that will, when
transformed, call procedure on the current syntactic environment.
procedure should compute and return a new form to be transformed,
in that same syntactic environment, in place of the form.
An example will make this clear. Suppose we wanted to define a simple
loop-until keyword equivalent to
(define-syntax loop-until
(syntax-rules ()
((loop-until id init test return step)
(letrec ((loop
(lambda (id)
(if test return (loop step)))))
(loop init)))))
The following attempt at defining loop-until has a subtle bug:
(define-syntax loop-until
(transformer
(lambda (exp env)
(let ((id (cadr exp))
(init (caddr exp))
(test (cadddr exp))
(return (cadddr (cdr exp)))
(step (cadddr (cddr exp)))
(close
(lambda (exp free)
(make-syntactic-closure env free exp))))
`(letrec ((loop
(lambda (,id)
(if ,(close test (list id))
,(close return (list id))
(loop ,(close step (list id)))))))
(loop ,(close init '())))))))
This definition appears to take all of the proper precautions to prevent
unintended captures. It carefully closes the subexpressions in their
original syntactic environment and it leaves the id identifier
free in the test, return, and step expressions, so
that it will be captured by the binding introduced by the lambda
expression. Unfortunately it uses the identifiers if and
loop within that lambda expression, so if the user of
loop-until just happens to use, say, if for the
identifier, it will be inadvertently captured.
The syntactic environment that if and loop want to be
exposed to is the one just outside the lambda expression: before
the user's identifier is added to the syntactic environment, but after
the identifier loop has been added.
capture-syntactic-environment captures exactly that environment
as follows:
(define-syntax loop-until
(transformer
(lambda (exp env)
(let ((id (cadr exp))
(init (caddr exp))
(test (cadddr exp))
(return (cadddr (cdr exp)))
(step (cadddr (cddr exp)))
(close
(lambda (exp free)
(make-syntactic-closure env free exp))))
`(letrec ((loop
,(capture-syntactic-environment
(lambda (env)
`(lambda (,id)
(,(make-syntactic-closure env '() `if)
,(close test (list id))
,(close return (list id))
(,(make-syntactic-closure env '()
`loop)
,(close step (list id)))))))))
(loop ,(close init '())))))))
In this case, having captured the desired syntactic environment, it is
convenient to construct syntactic closures of the identifiers if
and the loop and use them in the body of the
lambda.
A common use of capture-syntactic-environment is to get the
transformer environment of a macro transformer:
(transformer
(lambda (exp env)
(capture-syntactic-environment
(lambda (transformer-env)
...))))
This section describes the procedures that create and manipulate
identifiers. Previous syntactic closure proposals did not have an
identifier data type -- they just used symbols. The identifier data
type extends the syntactic closures facility to be compatible with the
high-level syntax-rules facility.
As discussed earlier, an identifier is either a symbol or an alias. An alias is implemented as a syntactic closure whose form is an identifier:
(make-syntactic-closure env '() 'a) => an alias
Aliases are implemented as syntactic closures because they behave just
like syntactic closures most of the time. The difference is that an
alias may be bound to a new value (for example by lambda or
let-syntax); other syntactic closures may not be used this way.
If an alias is bound, then within the scope of that binding it is looked
up in the syntactic environment just like any other identifier.
Aliases are used in the implementation of the high-level facility
syntax-rules. A macro transformer created by syntax-rules
uses a template to generate its output form, substituting subforms of
the input form into the template. In a syntactic closures
implementation, all of the symbols in the template are replaced by
aliases closed in the transformer environment, while the output form
itself is closed in the usage environment. This guarantees that the
macro transformation is hygienic, without requiring the transformer to
know the syntactic roles of the substituted input subforms.
#t if object is an identifier, otherwise returns
#f. Examples:
(identifier? 'a) => #t (identifier? (make-syntactic-closure env '() 'a)) => #t (identifier? "a") => #f (identifier? #\a) => #f (identifier? 97) => #f (identifier? #f) => #f (identifier? '(a)) => #f (identifier? '#(a)) => #f
The predicate eq? is used to determine if two identifers are
"the same". Thus eq? can be used to compare identifiers
exactly as it would be used to compare symbols. Often, though, it is
useful to know whether two identifiers "mean the same thing". For
example, the cond macro uses the symbol else to identify
the final clause in the conditional. A macro transformer for
cond cannot just look for the symbol else, because the
cond form might be the output of another macro transformer that
replaced the symbol else with an alias. Instead the transformer
must look for an identifier that "means the same thing" in the usage
environment as the symbol else means in the transformer
environment.
identifier=? returns #t if the meaning of
identifier1 in environment1 is the same as that of
identifier2 in environment2, otherwise it returns #f.
Examples:
(let-syntax
((foo
(transformer
(lambda (form env)
(capture-syntactic-environment
(lambda (transformer-env)
(identifier=? transformer-env 'x env 'x)))))))
(list (foo)
(let ((x 3))
(foo))))
=> (#t #f)
(let-syntax ((bar foo))
(let-syntax
((foo
(transformer
(lambda (form env)
(capture-syntactic-environment
(lambda (transformer-env)
(identifier=? transformer-env 'foo
env (cadr form))))))))
(list (foo foo)
(foobar))))
=> (#f #t)
The syntactic closures facility was invented by Alan Bawden and Jonathan
Rees. The use of aliases to implement syntax-rules was invented
by Alan Bawden (who prefers to call them synthetic names). Much
of this proposal is derived from an earlier proposal by Alan
Bawden.
macro:eval returns the value of expression in the current
top level environment. expression can contain macro definitions.
Side effects of expression will affect the top level
environment.
macro:load procedure reads Scheme source code expressions and
definitions from the file and evaluates them sequentially. These
source code expressions and definitions may contain macro definitions.
The macro:load procedure does not affect the values returned by
current-input-port and current-output-port.
This is version 2.1 of syntax-case, the low-level macro facility
proposed and implemented by Robert Hieb and R. Kent Dybvig.
This version is further adapted by Harald Hanche-Olsen <hanche@imf.unit.no> to make it compatible with, and easily usable with, SLIB. Mainly, these adaptations consisted of:
If you wish, you can see exactly what changes were done by reading the shell script in the file `syncase.sh'.
The two PostScript files were omitted in order to not burden the SLIB
distribution with them. If you do intend to use syntax-case,
however, you should get these files and print them out on a PostScript
printer. They are available with the original syntax-case
distribution by anonymous FTP in
`cs.indiana.edu:/pub/scheme/syntax-case'.
In order to use syntax-case from an interactive top level, execute:
(require 'syntax-case) (require 'repl) (repl:top-level macro:eval)
See the section Repl (See section Repl) for more information.
To check operation of syntax-case get `cs.indiana.edu:/pub/scheme/syntax-case', and type
(require 'syntax-case) (syncase:sanity-check)
Beware that syntax-case takes a long time to load -- about 20s on
a SPARCstation SLC (with SCM) and about 90s on a Macintosh SE/30 (with
Gambit).
All R4RS syntactic forms are defined, including delay. Along
with delay are simple definitions for make-promise (into
which delay expressions expand) and force.
syntax-rules and with-syntax (described in TR356)
are defined.
syntax-case is actually defined as a macro that expands into
calls to the procedure syntax-dispatch and the core form
syntax-lambda; do not redefine these names.
Several other top-level bindings not documented in TR356 are created:
build- procedures in `output.ss'
expand-syntax (the expander)
The syntax of define has been extended to allow (define id),
which assigns id to some unspecified value.
We have attempted to maintain R4RS compatibility where possible. The incompatibilities should be confined to `hooks.ss'. Please let us know if there is some incompatibility that is not flagged as such.
Send bug reports, comments, suggestions, and questions to Kent Dybvig (dyb@iuvax.cs.indiana.edu).
Included with the syntax-case files was `structure.scm'
which defines a macro define-structure. There is no
documentation for this macro and it is not used by any code in SLIB.
(bindings ...) forms...
(fluid-let ((variable init) ...) expression expression ...)
The inits are evaluated in the current environment (in some unspecified order), the current values of the variables are saved, the results are assigned to the variables, the expressions are evaluated sequentially in the current environment, the variables are restored to their original values, and the value of the last expression is returned.
The syntax of this special form is similar to that of let, but
fluid-let temporarily rebinds existing variables. Unlike
let, fluid-let creates no new bindings; instead it
assigns the values of each init to the binding (determined
by the rules of lexical scoping) of its corresponding
variable.
(require 'oop) or (require 'yasos)
`Yet Another Scheme Object System' is a simple object system for Scheme based on the paper by Norman Adams and Jonathan Rees: Object Oriented Programming in Scheme, Proceedings of the 1988 ACM Conference on LISP and Functional Programming, July 1988 [ACM #552880].
Another reference is:
Ken Dickey. Scheming with Objects AI Expert Volume 7, Number 10 (October 1992), pp. 24-33.
let). An
operation may be applied to any Scheme data object--not just instances.
As code which creates instances is just code, there are no classes
and no meta-anything. Method dispatch is by a procedure call a la
CLOS rather than by send syntax a la Smalltalk.
(opname self arg ...) default-body
(opname? object)
returns #t if object has an operation opname? and
#f otherwise.
((name self arg ...) body) ...
(name object arg ... executes the
body of the object with self bound to object and
with argument(s) arg....
((ancestor1 init1) ...) operation ...
let-like form of object for multiple inheritance. It
returns an object inheriting the behaviour of ancestor1 etc. An
operation will be invoked in an ancestor if the object itself does not
provide such a method. In the case of multiple inherited operations
with the same identity, the operation used is the one found in the first
ancestor in the ancestor list.
print operation is provided which is just (format
port obj) (See section Format (version 3.0)) for non-instances and prints
obj preceded by `#<INSTANCE>' for instances.
2 for a pair, 1 for a character
and by default id an error otherwise. Objects such as collections
(See section Collections) may override the default in an obvious way.
Setters implement generalized locations for objects
associated with some sort of mutable state. A getter operation
retrieves a value from a generalized location and the corresponding
setter operation stores a value into the location. Only the getter is
named -- the setter is specified by a procedure call as below. (Dylan
uses special syntax.) Typically, but not necessarily, getters are
access operations to extract values from Yasos objects (See section Yasos).
Several setters are predefined, corresponding to getters car,
cdr, string-ref and vector-ref e.g., (setter
car) is equivalent to set-car!.
This implementation of setters is similar to that in Dylan(TM)
(Dylan: An object-oriented dynamic language, Apple Computer
Eastern Research and Technology). Common LISP provides similar
facilities through setf.
string-ref is the getter corresponding to a setter which is
actually string-set!:
(define foo "foo") ((setter string-ref) foo 0 #\F) ; set element 0 of foo foo => "Foo"
set is equivalent to
set!. Otherwise, place must have the form of a procedure
call, where the procedure name refers to a getter and the call indicates
an accessible generalized location, i.e., the call would return a value.
The return value of set is usually unspecified unless used with a
setter whose definition guarantees to return a useful value.
(set (string-ref foo 2) #\O) ; generalized location with getter foo => "FoO" (set foo "foo") ; like set! foo => "foo"
define-operation defining an operation
getter-name that objects may support to return the value of some
mutable state. The default operation is to signal an error. The return
value is unspecified.
;;; These definitions for PRINT and SIZE are already supplied by
(require 'yasos)
(define-operation (print obj port)
(format port
(if (instance? obj) "#<instance>" "~s")
obj))
(define-operation (size obj)
(cond
((vector? obj) (vector-length obj))
((list? obj) (length obj))
((pair? obj) 2)
((string? obj) (string-length obj))
((char? obj) 1)
(else
(error "Operation not supported: size" obj))))
(define-predicate cell?)
(define-operation (fetch obj))
(define-operation (store! obj newValue))
(define (make-cell value)
(object
((cell? self) #t)
((fetch self) value)
((store! self newValue)
(set! value newValue)
newValue)
((size self) 1)
((print self port)
(format port "#<Cell: ~s>" (fetch self)))))
(define-operation (discard obj value)
(format #t "Discarding ~s~%" value))
(define (make-filtered-cell value filter)
(object-with-ancestors ((cell (make-cell value)))
((store! self newValue)
(if (filter newValue)
(store! cell newValue)
(discard self newValue)))))
(define-predicate array?)
(define-operation (array-ref array index))
(define-operation (array-set! array index value))
(define (make-array num-slots)
(let ((anArray (make-vector num-slots)))
(object
((array? self) #t)
((size self) num-slots)
((array-ref self index) (vector-ref anArray index))
((array-set! self index newValue) (vector-set! anArray index newValue))
((print self port) (format port "#<Array ~s>" (size self))))))
(define-operation (position obj))
(define-operation (discarded-value obj))
(define (make-cell-with-history value filter size)
(let ((pos 0) (most-recent-discard #f))
(object-with-ancestors
((cell (make-filtered-call value filter))
(sequence (make-array size)))
((array? self) #f)
((position self) pos)
((store! self newValue)
(operate-as cell store! self newValue)
(array-set! self pos newValue)
(set! pos (+ pos 1)))
((discard self value)
(set! most-recent-discard value))
((discarded-value self) most-recent-discard)
((print self port)
(format port "#<Cell-with-history ~s>" (fetch self))))))
(define-access-operation fetch)
(add-setter fetch store!)
(define foo (make-cell 1))
(print foo #f)
=> "#<Cell: 1>"
(set (fetch foo) 2)
=>
(print foo #f)
=> "#<Cell: 2>"
(fetch foo)
=> 2
(require 'precedence-parse) or (require 'parse)
This package implements:
This package offers improvements over previous parsers.
? is substituted for
missing input.
Here are the higher-level syntax types and an example of each. Precedence considerations are omitted for clarity. See section Grammar Rule Definition for full details.
bye
calls the function exit with no arguments.
- 42
Calls the function negate with the argument 42.
x - y
Calls the function difference with arguments x and y.
x + y + z
Calls the function sum with arguments x, y, and
y.
5 !
Calls the function factorial with the argument 5.
set foo bar
Calls the function set! with the arguments foo and
bar.
/* almost any text here */
Ignores the comment delimited by /* and */.
{0, 1, 2}
Calls the function list with the arguments 0, 1,
and 2.
f(x, y)
Calls the function funcall with the arguments f, x,
and y.
set foo bar;
delimits the extent of the restfix operator set.
prec:define-grammar.
The rules are appended to *syn-defs*. The value of
*syn-defs* is the grammar suitable for passing as an argument to
prec:parse.
*syn-ignore-whitespace*
In order to start defining a grammar, either
(set! *syn-defs* '())
or
(set! *syn-defs* *syn-ignore-whitespace*)
prec:define-grammar is used to define both the character classes
and rules for tokens.
Once your grammar is defined, save the value of *syn-defs* in a
variable (for use when calling prec:parse).
(define my-ruleset *syn-defs*)
prec:define-grammar and extracted from *syn-defs*.
The token delim may be a character, symbol, or string. A character delim argument will match only a character token; i.e. a character for which no token-group is assigned. A symbols or string will match only a token string; i.e. a token resulting from a token group.
prec:parse reads a ruleset grammar expression delimited
by delim from the given input port. prec:parse
returns the next object parsable from the given input port,
updating port to point to the first character past the end of the
external representation of the object.
If an end of file is encountered in the input before any characters are
found that can begin an object, then an end of file object is returned.
If a delimiter (such as delim) is found before any characters are
found that can begin an object, then #f is returned.
The port argument may be omitted, in which case it defaults to the
value returned by current-input-port. It is an error to parse
from a closed port.
tok:char-group was called with that character alone.
The argument chars-proc must be a procedure of one argument, a
list of characters. After tokenize has finished
accumulating the characters for a token, it calls chars-proc with
the list of characters. The value returned is the token which
tokenize returns.
The argument group may be an exact integer or a procedure of one
character argument. The following discussion concerns the treatment
which the tokenizing routine, tokenize, will accord to characters
on the basis of their groups.
When group is a non-zero integer, characters whose group number is equal to or exactly one less than group will continue to accumulate. Any other character causes the accumulation to stop (until a new token is to be read).
The group of zero is special. These characters are ignored when parsed pending a token, and stop the accumulation of token characters when the accumulation has already begun. Whitespace characters are usually put in group 0.
If group is a procedure, then, when triggerd by the occurence of an initial (no accumulation) chars character, this procedure will be repeatedly called with each successive character from the input stream until the group procedure returns a non-false value.
The following convenient constants are provided for use with
tok:char-group.
"0123456789".
char-whitespace? returns true.
This section describes advanced features. You can skip this section on first reading.
The Null Denotation (or nud) of a token is the procedure and arguments applying for that token when Left, an unclaimed parsed expression is not extant.
The Left Denotation (or led) of a token is the procedure, arguments, and lbp applying for that token when there is a Left, an unclaimed parsed expression.
In his paper,
Pratt, V. R. Top Down Operator Precendence. SIGACT/SIGPLAN Symposium on Principles of Programming Languages, Boston, 1973, pages 41-51
the left binding power (or lbp) was an independent property of tokens. I think this was done in order to allow tokens with NUDs but not LEDs to also be used as delimiters, which was a problem for statically defined syntaxes. It turns out that dynamically binding NUDs and LEDs allows them independence.
For the rule-defining procedures that follow, the variable tk may be a character, string, or symbol, or a list composed of characters, strings, and symbols. Each element of tk is treated as though the procedure were called for each element.
Character tk arguments will match only character tokens; i.e. characters for which no token-group is assigned. Symbols and strings will both match token strings; i.e. tokens resulting from token groups.
(list sop
arg1 ...) is incorporated.
If no NUD has been defined for a token; then if that token is a string, it is converted to a symbol and returned; if not a string, the token is returned.
If no LED has been defined for a token, and left is set, the parser issues a warning.
Here are procedures for defining rules for the syntax types introduced in section Precedence Parsing Overview.
For the rule-defining procedures that follow, the variable tk may be a character, string, or symbol, or a list composed of characters, strings, and symbols. Each element of tk is treated as though the procedure were called for each element.
For procedures prec:delim, ..., prec:prestfix, if the sop
argument is #f, then the token which triggered this rule is
converted to a symbol and returned. A false sop argument to the
procedures prec:commentfix, prec:matchfix, or prec:inmatchfix has a
different meaning.
Character tk arguments will match only character tokens; i.e. characters for which no token-group is assigned. Symbols and strings will both match token strings; i.e. tokens resulting from token groups.
prec:parse1 is called with binding-power bp.
prec:parse1; the resulting value is incorporated into the
expression being built. Otherwise, the list of sop and the
expression returned from prec:parse1 is incorporated.
Parsing of commentfix syntax differs from the others in several ways. It reads directly from input without tokenizing; It calls stp but does not return its value; nay any value. I added the stp argument so that comment text could be echoed.
0 until the token
match is reached. If the token sep does not appear between
each pair of expressions parsed, a warning is issued.
0 until the token
match is reached. If the token sep does not appear between
each pair of expressions parsed, a warning is issued.
Returns #t, #f or a string; has side effect of printing
according to format-string. If destination is #t,
the output is to the current output port and #t is returned. If
destination is #f, a formatted string is returned as the
result of the call. NEW: If destination is a string,
destination is regarded as the format string; format-string is
then the first argument and the output is returned as a string. If
destination is a number, the output is to the current error port
if available by the implementation. Otherwise destination must be
an output port and #t is returned.
format-string must be a string. In case of a formatting error
format returns #f and prints a message on the current output or
error port. Characters are output as if the string were output by the
display function with the exception of those prefixed by a tilde
(~). For a detailed description of the format-string syntax
please consult a Common LISP format reference manual. For a test suite
to verify this format implementation load `formatst.scm'. Please
send bug reports to lutzeb@cs.tu-berlin.de.
Note: format is not reentrant, i.e. only one format-call
may be executed at a time.
Please consult a Common LISP format reference manual for a detailed description of the format string syntax. For a demonstration of the implemented directives see `formatst.scm'.
This implementation supports directive parameters and modifiers
(: and @ characters). Multiple parameters must be
separated by a comma (,). Parameters can be numerical parameters
(positive or negative), character parameters (prefixed by a quote
character ('), variable parameters (v), number of rest
arguments parameter (#), empty and default parameters. Directive
characters are case independent. The general form of a directive
is:
directive ::= ~{directive-parameter,}[:][@]directive-character
directive-parameter ::= [ [-|+]{0-9}+ | 'character | v | # ]
Documentation syntax: Uppercase characters represent the corresponding control directive characters. Lowercase characters represent control directive parameter descriptions.
~A
display does).
~@A
~mincol,colinc,minpad,padcharA
~S
write does).
~@S
~mincol,colinc,minpad,padcharS
~D
~@D
~:D
~mincol,padchar,commacharD
~X
~@X
~:X
~mincol,padchar,commacharX
~O
~@O
~:O
~mincol,padchar,commacharO
~B
~@B
~:B
~mincol,padchar,commacharB
~nR
~n,mincol,padchar,commacharR
~@R
~:R
~:@R
~P
~@P
y and ies.
~:P
~P but jumps 1 argument backward.
~:@P
~@P but jumps 1 argument backward.
~C
~@C
#\ prefixing).
~:C
^C for ASCII 03).
~F
~width,digits,scale,overflowchar,padcharF
~@F
~E
Eee).
~width,digits,exponentdigits,scale,overflowchar,padchar,exponentcharE
~@E
~G
~width,digits,exponentdigits,scale,overflowchar,padchar,exponentcharG
~@G
~$
~digits,scale,width,padchar$
~@$
~:@$
~:$
~%
~n%
~&
~n&
~& and then n-1 newlines.
~|
~n|
~~
~n~
~<newline>
~:<newline>
~@<newline>
~T
~@T
~colnum,colincT
~?
~@?
~(str~)
string-downcase).
~:(str~)
string-capitalize.
~@(str~)
string-capitalize-first.
~:@(str~)
string-upcase.
~*
~n*
~:*
~n:*
~@*
~n@*
~[str0~;str1~;...~;strn~]
~n[
~@[
~:[
~;
~:;
~{str~}
~n{
~:{
~@{
~:@{
~^
~n^
~n,m^
~n,m,k^
~:A
#f as an empty list (see below).
~:S
#f as an empty list (see below).
~<~>
~:^
~mincol,padchar,commachar,commawidthD
~mincol,padchar,commachar,commawidthX
~mincol,padchar,commachar,commawidthO
~mincol,padchar,commachar,commawidthB
~n,mincol,padchar,commachar,commawidthR
~I
~F~@Fi with passed parameters for
~F.
~Y
~K
~?.
~!
~_
#\space character
~n_
#\space characters.
~/
#\tab character
~n/
#\tab characters.
~nC
integer->char. n must be a positive decimal number.~:S
#<...> as strings "#<...>" so that the format output can always
be processed by read.
~:A
#<...> as strings "#<...>" so that the format output can always
be processed by read.
~Q
~:Q
~F, ~E, ~G, ~$
Format has some configuration variables at the beginning of `format.scm' to suit the systems and users needs. There should be no modification necessary for the configuration that comes with SLIB. If modification is desired the variable should be set after the format code is loaded. Format detects automatically if the running scheme system implements floating point numbers and complex numbers.
symbol->string so the case type of the
printed symbols is implementation dependent.
format:symbol-case-conv is a one arg closure which is either
#f (no conversion), string-upcase, string-downcase
or string-capitalize. (default #f)
#f)
~E printing. (default
#\E)
~A, ~S,
~P, ~X uppercase printing. SLIB format 1.4 uses C-style
printf padding support which is completely replaced by the CL
format padding style.
~, which is not documented
(ignores all characters inside the format string up to a newline
character). (7.1 implements ~a, ~s,
~newline, ~~, ~%, numerical and variable
parameters and :/@ modifiers in the CL sense).
~A and ~S which print in
uppercase. (Elk implements ~a, ~s, ~~, and
~% (no directive parameters or modifiers)).
~a, ~s, ~c, ~%, and ~~ (no directive
parameters or modifiers)).
This implementation of format is solely useful in the SLIB context because it requires other components provided by SLIB.
requires printf and scanf and additionally defines
the symbols:
(current-input-port).
(current-output-port).
(current-error-port).
Each function converts, formats, and outputs its arg1 ... arguments according to the control string format argument and returns the number of characters output.
printf sends its output to the port (current-output-port).
fprintf sends its output to the port port. sprintf
string-set!s locations of the non-constant string argument
str to the output characters.
Note: sprintf should be changed to a macro so a
substringexpression could be used for the str argument.
The string format contains plain characters which are copied to the output stream, and conversion specifications, each of which results in fetching zero or more of the arguments arg1 .... The results are undefined if there are an insufficient number of arguments for the format. If format is exhausted while some of the arg1 ... arguments remain unused, the excess arg1 ... arguments are ignored.
The conversion specifications in a format string have the form:
% [ flags ] [ width ] [ . precision ] [ type ] conversion
An output conversion specifications consist of an initial `%' character followed in sequence by:
scanf functions with the `%i' conversion (see section Standard Formatted Input).
6. If the precision is explicitly 0,
the decimal point character is suppressed.
For the `%g' and `%G' conversions, the precision specifies how
many significant digits to print. Significant digits are the first
digit before the decimal point, and all the digits after it. If the
precision is 0 or not specified for `%g' or `%G', it is
treated like a value of 1. If the value being printed cannot be
expressed accurately in the specified number of digits, the value is
rounded to the nearest number that fits.
For exact conversions, if a precision is supplied it specifies the
minimum number of digits to appear; leading zeros are produced if
necessary. If a precision is not supplied, the number is printed with
as many digits as necessary. Converting an exact `0' with an
explicit precision of zero produces no characters.
scanf
for input (see section Standard Formatted Input).
Note: Inexact conversions are not supported yet.
write (which can be read using read); otherwise,
output is as display prints. A precision specifies the maximum
number of characters to output; otherwise as many characters as needed
are output.
Note: `%a' and `%A' are SLIB extensions.
Each function reads characters, interpreting them according to the control string format argument.
scanf-read-list returns a list of the items specified as far as
the input matches format. scanf, fscanf, and
sscanf return the number of items successfully matched and
stored. scanf, fscanf, and sscanf also set the
location corresponding to arg1 ... using the methods:
set!
set-car!
set-cdr!
vector-set!
substring-move-left!
The argument to a substring expression in arg1 ... must
be a non-constant string. Characters will be stored starting at the
position specified by the second argument to substring. The
number of characters stored will be limited by either the position
specified by the third argument to substring or the length of the
matched string, whichever is less.
The control string, format, contains conversion specifications and other characters used to direct interpretation of input sequences. The control string contains:
Unless the specification contains the `n' conversion character (described below), a conversion specification directs the conversion of the next input field. The result of a conversion specification is returned in the position of the corresponding argument points, unless `*' indicates assignment suppression. Assignment suppression provides a way to describe an input field to be skipped. An input field is defined as a string of characters; it extends to the next inappropriate character or until the field width, if specified, is exhausted.
Note: This specification of format strings differs from the ANSI C and POSIX specifications. In SLIB, white space before an input field is not skipped unless white space appears before the conversion specification in the format string. In order to write format strings which work identically with ANSI C and SLIB, prepend whitespace to all conversion specifications except `[' and `c'.
The conversion code indicates the interpretation of the input field; For a suppressed field, no value is returned. The following conversion codes are legal:
scanf. No input is consumed by %n.
scanf cannot read a null string.
The scanf functions terminate their conversions at end-of-file,
at the end of the control string, or when an input character conflicts
with the control string. In the latter case, the offending character is
left unread in the input stream.
This routine implements Posix command line argument parsing. Notice
that returning values through global variables means that getopt
is not reentrant.
(vector-ref argv *optind*)) that matches a letter in
optstring. argv is a vector or list of strings, the 0th of
which getopt usually ignores. argc is the argument count, usually
the length of argv. optstring is a string of recognized
option characters; if a character is followed by a colon, the option
takes an argument which may be immediately following it in the string or
in the next element of argv.
*optind* is the index of the next element of the argv vector
to be processed. It is initialized to 1 by `getopt.scm', and
getopt updates it when it finishes with each element of
argv.
getopt returns the next option character from argv that
matches a character in optstring, if there is one that matches.
If the option takes an argument, getopt sets the variable
*optarg* to the option-argument as follows:
getopt returns an error
indication.
If, when getopt is called, the string (vector-ref argv
*optind*) either does not begin with the character #\- or is
just "-", getopt returns #f without changing
*optind*. If (vector-ref argv *optind*) is the string
"--", getopt returns #f after incrementing
*optind*.
If getopt encounters an option character that is not contained in
optstring, it returns the question-mark #\? character. If
it detects a missing option argument, it returns the colon character
#\: if the first character of optstring was a colon, or a
question-mark character otherwise. In either case, getopt sets
the variable getopt:opt to the option character that caused the
error.
The special option "--" can be used to delimit the end of the
options; #f is returned, and "--" is skipped.
RETURN VALUE
getopt returns the next option character specified on the command
line. A colon #\: is returned if getopt detects a missing argument
and the first character of optstring was a colon #\:.
A question-mark #\? is returned if getopt encounters an option
character not in optstring or detects a missing argument and the first
character of optstring was not a colon #\:.
Otherwise, getopt returns #f when all command line options have been
parsed.
Example:
#! /usr/local/bin/scm
;;;This code is SCM specific.
(define argv (program-arguments))
(require 'getopt)
(define opts ":a:b:cd")
(let loop ((opt (getopt (length argv) argv opts)))
(case opt
((#\a) (print "option a: " *optarg*))
((#\b) (print "option b: " *optarg*))
((#\c) (print "option c"))
((#\d) (print "option d"))
((#\?) (print "error" getopt:opt))
((#\:) (print "missing arg" getopt:opt))
((#f) (if (< *optind* (length argv))
(print "argv[" *optind* "]="
(list-ref argv *optind*)))
(set! *optind* (+ *optind* 1))))
(if (< *optind* (length argv))
(loop (getopt (length argv) argv opts))))
(slib:exit)
getopt-- is an extended version of getopt
which parses long option names of the form
`--hold-the-onions' and `--verbosity-level=extreme'.
Getopt-- behaves as getopt except for non-empty
options beginning with `--'.
Options beginning with `--' are returned as strings rather than
characters. If a value is assigned (using `=') to a long option,
*optarg* is set to the value. The `=' and value are
not returned as part of the option string.
No information is passed to getopt-- concerning which long
options should be accepted or whether such options can take arguments.
If a long option did not have an argument, *optarg will be set to
#f. The caller is responsible for detecting and reporting
errors.
(define opts ":-:b:")
(define argc 5)
(define argv '("foo" "-b9" "--f1" "--2=" "--g3=35234.342" "--"))
(define *optind* 1)
(define *optarg* #f)
(require 'qp)
(do ((i 5 (+ -1 i)))
((zero? i))
(define opt (getopt-- argc argv opts))
(print *optind* opt *optarg*)))
-|
2 #\b "9"
3 "f1" #f
4 "2" ""
5 "g3" "35234.342"
5 #f "35234.342"
read-command converts a command line into a list of strings
suitable for parsing by getopt. The syntax of command lines
supported resembles that of popular shells. read-command
updates port to point to the first character past the command
delimiter.
If an end of file is encountered in the input before any characters are found that can begin an object or comment, then an end of file object is returned.
The port argument may be omitted, in which case it defaults to the
value returned by current-input-port.
The fields into which the command line is split are delimited by
whitespace as defined by char-whitespace?. The end of a command
is delimited by end-of-file or unescaped semicolon (;) or
newline. Any character can be literally included in a field by
escaping it with a backslach (\).
The initial character and types of fields recognized are:
read starting with this character. The
read expression is evaluated, converted to a string
(using display), and replaces the expression in the returned
field.
The comment field differs from the previous fields in that it must be
the first character of a command or appear after whitespace in order to
be recognized. # can be part of fields if these conditions are
not met. For instance, ab#c is just the field ab#c.
read-dommand-line and backslashes before newlines in
comments are also ignored.
read-options-file converts an options file into a list of
strings suitable for parsing by getopt. The syntax of options
files is the same as the syntax for command
lines, except that newlines do not terminate reading (only ;
or end of file).
If an end of file is encountered before any characters are found that can begin an object or comment, then an end of file object is returned.
Arguments to procedures in scheme are distinguished from each other by their position in the procedure call. This can be confusing when a procedure takes many arguments, many of which are not often used.
A parameter-list is a way of passing named information to a procedure. Procedures are also defined to set unused parameters to default values, check parameters, and combine parameter lists.
A parameter has the form (parameter-name value1
...). This format allows for more than one value per
parameter-name.
A parameter-list is a list of parameters, each with a different parameter-name.
parameter-list-ref returns the value of parameter
parameter-name of parameter-list.
make-parameter-list
which created parameter-list. For each non-false element of
expanders that procedure is mapped over the corresponding
parameter value and the returned parameter lists are merged into
parameter-list.
This process is repeated until parameter-list stops growing. The
value returned from parameter-list-expand is unspecified.
make-parameter-list
which created parameter-list. fill-empty-parameters
returns a new parameter-list with each empty parameter replaced with the
list returned by calling the corresponding defaulter with
parameter-list as its argument.
make-parameter-list
which created parameter-list.
check-parameters returns parameter-list if each check
of the corresponding parameter-list returns non-false. If some
check returns #f an error is signaled.
In the following procedures arities is a list of symbols. The
elements of arities can be:
single
optional
boolean
nary
nary1
single and boolean are converted to
the single value associated with them. The other arity types are
converted to lists of the value(s) of type types.
positions is a list of positive integers whose order matches the
order of the parameter-names in the call to
make-parameter-list which created parameter-list. The
integers specify in which argument position the corresponding parameter
should appear.
getopt. Longer
strings will be treated as long-named options (see section Getopt).
getopt->parameter-list, but converts argv to an
argument-list as specified by optnames, positions,
arities, types, defaulters, checks, and
aliases.
These getopt functions can be used with SLIB relational
databases. For an example, See section Database Utilities.
If errors are encountered while processing options, directions for using
the options are printed to current-error-port.
(begin
(set! *optind* 1)
(getopt->parameter-list
2
'("cmd" "-?")
'(flag number symbols symbols string flag2 flag3 num2 num3)
'(boolean optional nary1 nary single boolean boolean nary nary)
'(boolean integer symbol symbol string boolean boolean integer integer)
'(("flag" flag)
("f" flag)
("Flag" flag2)
("B" flag3)
("optional" number)
("o" number)
("nary1" symbols)
("N" symbols)
("nary" symbols)
("n" symbols)
("single" string)
("s" string)
("a" num2)
("Abs" num3))))
-|
Usage: cmd [OPTION ARGUMENT ...] ...
-f, --flag
-o, --optional=<number>
-n, --nary=<symbols> ...
-N, --nary1=<symbols> ...
-s, --single=<string>
--Flag
-B
-a <num2> ...
--Abs=<num3> ...
ERROR: getopt->parameter-list "unrecognized option" "-?"
The batch procedures provide a way to write and execute portable scripts
for a variety of operating systems. Each batch: procedure takes
as its first argument a parameter-list (see section Parameter lists). This
parameter-list argument parms contains named associations. Batch
currently uses 2 of these:
batch-port
batch-dialect
`batch.scm' uses 2 enhanced relational tables (see section Database Utilities) to store information linking the names of
operating-systems to batch-dialectes.
operating-system and batch-dialect tables and adds
the domain operating-system to the enhanced relational database
database.
batch:platform is set to (software-type)
(see section Configuration) unless (software-type) is unix,
in which case finer distinctions are made.
batch:call-with-output-script writes an appropriate
header to file and then calls proc with file as the
only argument. If file is a string,
batch:call-with-output-script opens a output-file of name
file, writes an appropriate header to file, and then calls
proc with the newly opened port as the only argument. Otherwise,
batch:call-with-output-script acts as if it was called with the
result of (current-output-port) as its third argument.
#t if successful, #f if not.
batch:apply-chop-to-fit calls proc with arg1,
arg2, ..., and chunk, where chunk is a subset of
list. batch:apply-chop-to-fit tries proc with
successively smaller subsets of list until either proc
returns non-false, or the chunks become empty.
The rest of the batch: procedures write (or execute if
batch-dialect is system) commands to the batch port which
has been added to parms or (copy-tree parms) by the
code:
(adjoin-parameters! parms (list 'batch-port port))
batch:try-system (below) with arguments, but signals an
error if batch:try-system returns #f.
These functions return a non-false value if the command was successfully
translated into the batch dialect and #f if not. In the case of
the system dialect, the value is non-false if the operation
suceeded.
batch-port in parms which executes
the program named string1 with arguments string2 ....
batch-port in parms which executes
the batch script named string1 with arguments string2
....
Note: batch:run-script and batch:try-system are not the
same for some operating systems (VMS).
batch-port in
parms.
batch-port in parms which create a
file named file with contents line1 ....
batch-port in parms which deletes
the file named file.
batch-port in parms which renames
the file old-name to new-name.
In addition, batch provides some small utilities very useful for writing scripts:
(truncate-up-to "/usr/local/lib/slib/batch.scm" "/") => "batch.scm"
str but with the suffix string old
removed and the suffix string new appended. If the end of
str does not match old, an error is signaled.
(replace-suffix "/usr/local/lib/slib/batch.scm" ".scm" ".c") => "/usr/local/lib/slib/batch.c"
equal? to elements of
list2, then those elements will appear first and in the order of
list1.
equal? to elements of
list1, then those elements will appear last and in the order of
list2.
batch-dialect to be used for the
operating-system named osname. os->batch-dialect uses the
tables added to database by batch:initialize!.
Here is an example of the use of most of batch's procedures:
(require 'database-utilities)
(require 'parameters)
(require 'batch)
(define batch (create-database #f 'alist-table))
(batch:initialize! batch)
(define my-parameters
(list (list 'batch-dialect (os->batch-dialect batch:platform))
(list 'platform batch:platform)
(list 'batch-port (current-output-port)))) ;gets filled in later
(batch:call-with-output-script
my-parameters
"my-batch"
(lambda (batch-port)
(adjoin-parameters! my-parameters (list 'batch-port batch-port))
(and
(batch:comment my-parameters
"================ Write file with C program.")
(batch:rename-file my-parameters "hello.c" "hello.c~")
(batch:lines->file my-parameters "hello.c"
"#include <stdio.h>"
"int main(int argc, char **argv)"
"{"
" printf(\"hello world\\n\");"
" return 0;"
"}" )
(batch:system my-parameters "cc" "-c" "hello.c")
(batch:system my-parameters "cc" "-o" "hello"
(replace-suffix "hello.c" ".c" ".o"))
(batch:system my-parameters "hello")
(batch:delete-file my-parameters "hello")
(batch:delete-file my-parameters "hello.c")
(batch:delete-file my-parameters "hello.o")
(batch:delete-file my-parameters "my-batch")
)))
Produces the file `my-batch':
#!/bin/sh
# "my-batch" build script created Sat Jun 10 21:20:37 1995
# ================ Write file with C program.
mv -f hello.c hello.c~
rm -f hello.c
echo '#include <stdio.h>'>>hello.c
echo 'int main(int argc, char **argv)'>>hello.c
echo '{'>>hello.c
echo ' printf("hello world\n");'>>hello.c
echo ' return 0;'>>hello.c
echo '}'>>hello.c
cc -c hello.c
cc -o hello hello.o
hello
rm -f hello
rm -f hello.c
rm -f hello.o
rm -f my-batch
When run, `my-batch' prints:
bash$ my-batch mv: hello.c: No such file or directory hello world
generic-write is a procedure that transforms a Scheme data value
(or Scheme program expression) into its textual representation and
prints it. The interface to the procedure is sufficiently general to
easily implement other useful formatting procedures such as pretty
printing, output to a string and truncated output.
#f to stop the transformation.
The value returned by generic-write is undefined.
Examples:
(write obj) == (generic-write obj #f #f display-string) (display obj) == (generic-write obj #t #f display-string)
where
display-string == (lambda (s) (for-each write-char (string->list s)) #t)
pretty-prints obj on port. If port is not
specified, current-output-port is used.
Example:
(pretty-print '((1 2 3 4 5) (6 7 8 9 10) (11 12 13 14 15)
(16 17 18 19 20) (21 22 23 24 25)))
-| ((1 2 3 4 5)
-| (6 7 8 9 10)
-| (11 12 13 14 15)
-| (16 17 18 19 20)
-| (21 22 23 24 25))
(current-output-port).
outfile is a port or a string. If no outfile is specified
then current-output-port is assumed. These expanded expressions
are then pretty-printed to this port.
Whitepsace and comments (introduced by ;) which are not part of
scheme expressions are reproduced in the output. This procedure does
not affect the values returned by current-input-port and
current-output-port.
pprint-filter-file can be used to pre-compile macro-expansion and
thus can reduce loading time. The following will write into
`exp-code.scm' the result of expanding all defmacros in
`code.scm'.
(require 'pprint-file) (require 'defmacroexpand) (defmacro:load "my-macros.scm") (pprint-filter-file "code.scm" defmacro:expand* "exp-code.scm")
(require 'posix-time)
decode-universal-time.
decode-universal-time.
localtime sets the
variable *timezone* with the difference between Coordinated
Universal Time (UTC) and local standard time in seconds
(see section Time Zone).
"Wed Jun 30 21:49:08 1993".
(asctime (gmtime caltime)),
(asctime (localtime caltime)), and
(asctime (localtime caltime tz)), respectively.
(decode-universal-time (get-universal-time)).
current-time.
gmtime and localtime.
gmtime and localtime.
Notice that the values returned by decode-universal-time do not
match the arguments to encode-universal-time.
Notice that the values returned by decode-universal-time do not
match the arguments to encode-universal-time.
Note: The Tektronix graphics support files need more work, and are not complete.
The Tektronix 4000 series graphics protocol gives the user a 1024 by 1024 square drawing area. The origin is in the lower left corner of the screen. Increasing y is up and increasing x is to the right.
The graphics control codes are sent over the current-output-port and can be mixed with regular text and ANSI or other terminal control sequences.
The graphics control codes are sent over the current-output-port and can be mixed with regular text and ANSI or other terminal control sequences.
The bit-twiddling functions are made available through the use of the
logical package. logical is loaded by inserting
(require 'logical) before the code that uses these
functions.
Example:
(number->string (logand #b1100 #b1010) 2) => "1000"
Example:
(number->string (logior #b1100 #b1010) 2) => "1110"
Example:
(number->string (logxor #b1100 #b1010) 2) => "110"
Example:
(number->string (lognot #b10000000) 2) => "-10000001" (number->string (lognot #b0) 2) => "-1"
(logtest j k) == (not (zero? (logand j k))) (logtest #b0100 #b1011) => #f (logtest #b0100 #b0111) => #t
(logbit? index j) == (logtest (integer-expt 2 index) j) (logbit? 0 #b1101) => #t (logbit? 1 #b1101) => #f (logbit? 2 #b1101) => #t (logbit? 3 #b1101) => #t (logbit? 4 #b1101) => #f
(inexact->exact (floor (* int (expt 2 count)))).
Example:
(number->string (ash #b1 3) 2) => "1000" (number->string (ash #b1010 -1) 2) => "101"
Example:
(logcount #b10101010) => 4 (logcount 0) => 0 (logcount -2) => 1
Example:
(integer-length #b10101010) => 8 (integer-length 0) => 0 (integer-length #b1111) => 4
Example:
(integer-expt 2 5) => 32 (integer-expt -3 3) => -27
Example:
(number->string (bit-extract #b1101101010 0 4) 2) => "1010" (number->string (bit-extract #b1101101010 4 9) 2) => "10110"
(d x y) such that d = gcd(n1,
n2) = n1 * x + n2 * y.
(quotient (+ -1 n) -2) for positive odd integer n.
modular: procedures.
(modulo n (modulus->integer
modulus)) in the representation specified by modulus.
The rest of these functions assume normalized arguments; That is, the arguments are constrained by the following table:
For all of these functions, if the first argument (modulus) is:
positive?
zero?
negative?
(+ 1 (* -2 modulus)), but with symmetric
representation; i.e. (<= (- modulus) n
modulus).
If all the arguments are fixnums the computation will use only fixnums.
#t if there exists an integer n such that k * n
== 1 mod modulus, and #f otherwise.
The Scheme code for modular:* with negative modulus is not
completed for fixnum-only implementations.
This package tests and generates prime numbers. The strategy used is as follows:
The Miller-Rabin test is a Monte-Carlo test--in other words, it's fast and it gets the right answer with high probability. For a candidate that is prime, the Miller-Rabin test is certain to report "prime"; it will never report "composite". However, for a candidate that is composite, there is a (small) probability that the Miller-Rabin test will erroneously report "prime". This probability can be made arbitarily small by adjusting the number of iterations of the Miller-Rabin test.
#t if candidate is probably prime. The optional
parameter iter controls the number of iterations of the
Miller-Rabin test. The probability of a composite candidate being
mistaken for a prime is at most (1/4)^iter. The default value of
iter is 15, which makes the probability less than 1 in 10^9.
count odd probable primes less (more)
than or equal to start. The optional parameter iter
controls the number of iterations of the Miller-Rabin test for each
candidate. The probability of a composite candidate being mistaken for
a prime is at most (1/4)^iter. The default value of iter
is 15, which makes the probability less than 1 in 10^9.
Rabin and Miller's result can be summarized as follows. Let p
(the candidate prime) be any odd integer greater than 2. Let b
(the "base") be an integer in the range 2 ... p-1. There is a
fairly simple Boolean function--call it C, for
"Composite"---with the following properties:
p is prime, C(p, b) is false for all b in the range
2 ... p-1.
p is composite, C(p, b) is false for at most 1/4 of all
b in the range 2 ... p-1. (If the test fails for base
b, p is called a strong pseudo-prime to base
b.)
For details of C, and why it fails for at most 1/4 of the
potential bases, please consult a book on number theory or cryptography
such as "A Course in Number Theory and Cryptography" by Neal Koblitz,
published by Springer-Verlag 1994.
There is nothing probablistic about this result. It's true for all
p. If we had time to test (1/4)p + 1 different bases, we
could definitively determine the primality of p. For large
candidates, that would take much too long--much longer than the simple
approach of dividing by all numbers up to sqrt(p). This is
where probability enters the picture.
Suppose we have some candidate prime p. Pick a random integer
b in the range 2 ... p-1. Compute C(p,b). If
p is prime, the result will certainly be false. If p is
composite, the probability is at most 1/4 that the result will be false
(demonstrating that p is a strong pseudoprime to base b).
The test can be repeated with other random bases. If p is prime,
each test is certain to return false. If p is composite, the
probability of C(p,b) returning false is at most 1/4 for each
test. Since the b are chosen at random, the tests outcomes are
independent. So if p is composite and the test is repeated, say,
15 times, the probability of it returning false all fifteen times is at
most (1/4)^15, or about 10^-9. If the test is repeated 30 times, the
probability of failure drops to at most 8.3e-25.
Rabin and Miller's result holds for all candidates p.
However, if the candidate p is picked at random, the probability
of the Miller-Rabin test failing is much less than the computed bound.
This is because, for most composite numbers, the fraction of
bases that cause the test to fail is much less than 1/4. For example,
if you pick a random odd number less than 1000 and apply the
Miller-Rabin test with only 3 random bases, the computed failure bound
is (1/4)^3, or about 1.6e-2. However, the actual probability of failure
is much less--about 7.2e-5. If you accidentally pick 703 to test for
primality, the probability of failure is (161/703)^3, or about 1.2e-2,
which is almost as high as the computed bound. This is because 703 is a
strong pseudoprime to 161 bases. But if you pick at random there is
only a small chance of picking 703, and no other number less than 1000
has that high a percentage of pseudoprime bases.
The Miller-Rabin test is sometimes used in a slightly different fashion, where it can, at least in principle, cause problems. The weaker version uses small prime bases instead of random bases. If you are picking candidates at random and testing for primality, this works well since very few composites are strong pseudo-primes to small prime bases. (For example, there is only one composite less than 2.5e10 that is a strong pseudo-prime to the bases 2, 3, 5, and 7.) The problem with this approach is that once a candidate has been picked, the test is deterministic. This distinction is subtle, but real. With the randomized test, for any candidate you pick--even if your candidate-picking procedure is strongly biased towards troublesome numbers, the test will work with high probability. With the deterministic version, for any particular candidate, the test will either work (with probability 1), or fail (with probability 1). It won't fail for very many candidates, but that won't be much consolation if your candidate-picking procedure is somehow biased toward troublesome numbers.
(sort! (factor k) <).Note: The rest of these procedures implement the Solovay-Strassen primality test. This test has been superseeded by the faster See section Prime Testing and Generation. However these are left here as they take up little space and may be of use to an implementation without bignums.
See Robert Solovay and Volker Strassen, A Fast Monte-Carlo Test for Primality, SIAM Journal on Computing, 1977, pp 84-85.
#f if p is composite; #t if p is
prime. There is a slight chance (expt 2 (- prime:trials)) that a
composite will return #t.
The optional argument state must be of the type produced by
(make-random-state). It defaults to the value of the variable
*random-state*. This object is used to maintain the state of the
pseudo-random-number generator and is altered as a side effect of the
random operation.
random uses by default. The nature
of this data structure is implementation-dependent. It may be printed
out and successfully read back in, but may or may not function correctly
as a random-number state object in another implementation.
*random-state* and as a second argument to
random. If argument state is given, a copy of it is
returned. Otherwise a copy of *random-state* is returned.If inexact numbers are support by the Scheme implementation, `randinex.scm' will be loaded as well. `randinex.scm' contains procedures for generating inexact distributions.
(vector-length vect), the
coordinates are uniformly distributed within the unit n-shere.
The sum of the squares of the numbers is returned.
(vector-length vect), the coordinates are
uniformly distributed over the surface of the unit n-shere.
(+ m (* d
(random:normal))).
The integer degree, if given, specifies the degree of the polynomial being computed -- which is also the number of bits computed in the checksums. The default value is 32.
The integer generator specifies the polynomial being computed. The power of 2 generating each 1 bit is the exponent of a term of the polynomial. The bit at position degree is implicit and should not be part of generator. This allows systems with numbers limited to 32 bits to calculate 32 bit checksums. The default value of generator when degree is 32 (its default) is:
(make-port-crc 32 #b00000100110000010001110110110111)
Creates a procedure to calculate the P1003.2/D11.2 (POSIX.2) 32-bit checksum from the polynomial:
32 26 23 22 16 12 11
( x + x + x + x + x + x + x +
10 8 7 5 4 2 1
x + x + x + x + x + x + x + 1 ) mod 2
(require 'make-crc) (define crc32 (slib:eval (make-port-crc))) (define (file-check-sum file) (call-with-input-file file crc32)) (file-check-sum (in-vicinity (library-vicinity) "ratize.scm")) => 3553047446
The plotting procedure is made available through the use of the
charplot package. charplot is loaded by inserting
(require 'charplot) before the code that uses this
procedure.
Example:
(require 'charplot)
(set! charplot:height 19)
(set! charplot:width 45)
(define (make-points n)
(if (zero? n)
'()
(cons (cons (/ n 6) (sin (/ n 6))) (make-points (1- n)))))
(plot! (make-points 37) "x" "Sin(x)")
-|
Sin(x) ______________________________________________
1.25|- |
| |
1|- **** |
| ** ** |
750.0e-3|- * * |
| * * |
500.0e-3|- * * |
| * |
250.0e-3|- * |
| * * |
0|-------------------*--------------------------|
| * |
-250.0e-3|- * * |
| * * |
-500.0e-3|- * |
| * * |
-750.0e-3|- * * |
| ** ** |
-1|- **** |
|____________:_____._____:_____._____:_________|
x 2 4
#f if such an integer can't be found.
To find the closest integer to a given integers square root:
(define (integer-sqrt y) (newton:find-integer-root (lambda (x) (- (* x x) y)) (lambda (x) (* 2 x)) (ash 1 (quotient (integer-length y) 2)))) (integer-sqrt 15) => 4
abs(f(x)) is less than prec; or
returns #f if such a real can't be found.
If prec is instead a negative integer, newton:find-root
returns the result of -prec iterations.
H. J. Orchard, The Laguerre Method for Finding the Zeros of Polynomials, IEEE Transactions on Circuits and Systems, Vol. 36, No. 11, November 1989, pp 1377-1381.
There are 2 errors in Orchard's Table II. Line k=2 for starting value of 1000+j0 should have Z_k of 1.0475 + j4.1036 and line k=2 for starting value of 0+j1000 should have Z_k of 1.0988 + j4.0833.
magnitude(f(z)) is less than prec; or returns
#f if such a number can't be found.
If prec is instead a negative integer, laguerre:find-root
returns the result of -prec iterations.
magnitude(f(z)) is less than prec; or
returns #f if such a number can't be found.
If prec is instead a negative integer,
laguerre:find-polynomial-root returns the result of -prec
iterations.
Scheme provides a consistent and capable set of numeric functions. Inexacts implement a field; integers a commutative ring (and Euclidean domain). This package allows the user to use basic Scheme numeric functions with symbols and non-numeric elements of commutative rings.
The commutative-ring package makes +, -, *,
/, and ^ careful in the sense that any non-numeric
arguments which it cannot reduce appear in the expression output. In
order to see what working with this package is like, self-set all the
single letter identifiers (to their corresponding symbols).
(define a 'a) ... (define z 'z)
Or just (require 'self-set). Now for some sample expressions:
(* (+ a b) (+ a b)) => (+ (* 2 a b) (^ a 2) (^ b 2)) (* (+ a b) (- a b)) => (- (^ a 2) (^ b 2)) (* (- a b) (- a b)) => (- (+ (^ a 2) (^ b 2)) (* 2 a b)) (* (- a b) (+ a b)) => (- (^ a 2) (^ b 2)) (/ (+ a b) (+ c d)) => (+ (/ a (+ c d)) (/ b (+ c d))) (/ (+ a b) (- c d)) => (+ (/ a (- c d)) (/ b (- c d))) (/ (- a b) (- c d)) => (- (/ a (- c d)) (/ b (- c d))) (/ (- a b) (+ c d)) => (- (/ a (+ c d)) (/ b (+ c d))) (^ (+ a b) 3) => (+ (* 3 a (^ b 2)) (* 3 b (^ a 2)) (^ a 3) (^ b 3)) (^ (+ a 2) 3) => (+ 8 (* a 12) (* (^ a 2) 6) (^ a 3))
Use of this package is not restricted to simple arithmetic expressions:
(require 'determinant) (determinant '((a b c) (d e f) (g h i))) => (- (+ (* a e i) (* b f g) (* c d h)) (* a f h) (* b d i) (* c e g))
The commutative-ring package differs from other extension
mechanisms in that it automatically, using properties true of all
commutative rings, simplifies sum and product expressions containing
non-numeric elements. One need only specify behavior for + or
* for cases where expressions involving objects reduce to numbers
or to expressions involving different non-numeric elements.
Currently, only +, -, *, /, and ^
support non-numeric elements. Expressions with - are converted
to equivalent expressions without -, so behavior for - is
not defined separately. / expressions are handled similarly.
This list might be extended to include quotient, modulo,
remainder, lcm, and gcd; but these work only for
the more restrictive Euclidean (Unique Factorization) Domain.
cars are sub-op1 and
sub-op2, respectively. The argument reduction is a
procedure accepting 2 arguments which will be lists whose cars
are sub-op1 and sub-op2.
car is sub-op1, and
some other argument. Reduction will be called with the list whose
car is sub-op1 and some other argument.
If reduction returns #f, the reduction has failed and other
reductions will be tried. If reduction returns a non-false value,
that value will replace the two arguments in arithmetic (+,
-, and *) calculations involving non-numeric elements.
The operations + and * are assumed commutative; hence both
orders of arguments to reduction will be tried if necessary.
The following rule is the built-in definition for distributing *
over +.
(cring:define-rule '* '+ 'identity (lambda (exp1 exp2) (apply + (map (lambda (trm) (* trm exp2)) (cdr exp1))))))
The first step in creating your commutative ring is to write procedures to create elements of the ring. A non-numeric element of the ring must be represented as a list whose first element is a symbol or string. This first element identifies the type of the object. A convenient and clear convention is to make the type-identifying element be the same symbol whose top-level value is the procedure to create it.
(define (n . list1)
(cond ((and (= 2 (length list1))
(eq? (car list1) (cadr list1)))
0)
((not (term< (first list1) (last1 list1)))
(apply n (reverse list1)))
(else (cons 'n list1))))
(define (s x y) (n x y))
(define (m . list1)
(cond ((neq? (first list1) (term_min list1))
(apply m (cyclicrotate list1)))
((term< (last1 list1) (cadr list1))
(apply m (reverse (cyclicrotate list1))))
(else (cons 'm list1))))
Define a procedure to multiply 2 non-numeric elements of the ring. Other multiplicatons are handled automatically. Objects for which rules have not been defined are not changed.
(define (n*n ni nj)
(let ((list1 (cdr ni)) (list2 (cdr nj)))
(cond ((null? (intersection list1 list2)) #f)
((and (eq? (last1 list1) (first list2))
(neq? (first list1) (last1 list2)))
(apply n (splice list1 list2)))
((and (eq? (first list1) (first list2))
(neq? (last1 list1) (last1 list2)))
(apply n (splice (reverse list1) list2)))
((and (eq? (last1 list1) (last1 list2))
(neq? (first list1) (first list2)))
(apply n (splice list1 (reverse list2))))
((and (eq? (last1 list1) (first list2))
(eq? (first list1) (last1 list2)))
(apply m (cyclicsplice list1 list2)))
((and (eq? (first list1) (first list2))
(eq? (last1 list1) (last1 list2)))
(apply m (cyclicsplice (reverse list1) list2)))
(else #f))))
Test the procedures to see if they work.
;;; where cyclicrotate(list) is cyclic rotation of the list one step
;;; by putting the first element at the end
(define (cyclicrotate list1)
(append (rest list1) (list (first list1))))
;;; and where term_min(list) is the element of the list which is
;;; first in the term ordering.
(define (term_min list1)
(car (sort list1 term<)))
(define (term< sym1 sym2)
(string<? (symbol->string sym1) (symbol->string sym2)))
(define first car)
(define rest cdr)
(define (last1 list1) (car (last-pair list1)))
(define (neq? obj1 obj2) (not (eq? obj1 obj2)))
;;; where splice is the concatenation of list1 and list2 except that their
;;; common element is not repeated.
(define (splice list1 list2)
(cond ((eq? (last1 list1) (first list2))
(append list1 (cdr list2)))
(else (error 'splice list1 list2))))
;;; where cyclicsplice is the result of leaving off the last element of
;;; splice(list1,list2).
(define (cyclicsplice list1 list2)
(cond ((and (eq? (last1 list1) (first list2))
(eq? (first list1) (last1 list2)))
(butlast (splice list1 list2) 1))
(else (error 'cyclicsplice list1 list2))))
(N*N (S a b) (S a b)) => (m a b)
Then register the rule for multiplying type N objects by type N objects.
(cring:define-rule '* 'N 'N N*N))
Now we are ready to compute!
(define (t)
(define detM
(+ (* (S g b)
(+ (* (S f d)
(- (* (S a f) (S d g)) (* (S a g) (S d f))))
(* (S f f)
(- (* (S a g) (S d d)) (* (S a d) (S d g))))
(* (S f g)
(- (* (S a d) (S d f)) (* (S a f) (S d d))))))
(* (S g d)
(+ (* (S f b)
(- (* (S a g) (S d f)) (* (S a f) (S d g))))
(* (S f f)
(- (* (S a b) (S d g)) (* (S a g) (S d b))))
(* (S f g)
(- (* (S a f) (S d b)) (* (S a b) (S d f))))))
(* (S g f)
(+ (* (S f b)
(- (* (S a d) (S d g)) (* (S a g) (S d d))))
(* (S f d)
(- (* (S a g) (S d b)) (* (S a b) (S d g))))
(* (S f g)
(- (* (S a b) (S d d)) (* (S a d) (S d b))))))
(* (S g g)
(+ (* (S f b)
(- (* (S a f) (S d d)) (* (S a d) (S d f))))
(* (S f d)
(- (* (S a b) (S d f)) (* (S a f) (S d b))))
(* (S f f)
(- (* (S a d) (S d b)) (* (S a b) (S d d))))))))
(* (S b e) (S c a) (S e c)
detM
))
(pretty-print (t))
-|
(- (+ (m a c e b d f g)
(m a c e b d g f)
(m a c e b f d g)
(m a c e b f g d)
(m a c e b g d f)
(m a c e b g f d))
(* 2 (m a b e c) (m d f g))
(* (m a c e b d) (m f g))
(* (m a c e b f) (m d g))
(* (m a c e b g) (m d f)))
(require 'determinant) (determinant '((1 2) (3 4))) => -2 (determinant '((1 2 3) (4 5 6) (7 8 9))) => 0 (determinant '((1 2 3 4) (5 6 7 8) (9 10 11 12))) => 0
A base table implementation using Scheme association lists is available
as the value of the identifier alist-table after doing:
Association list base tables are suitable for small databases and support all Scheme types when temporary and readable/writeable Scheme types when saved. I hope support for other base table implementations will be added in the future.
This rest of this section documents the interface for a base table implementation from which the section Relational Database package constructs a Relational system. It will be of interest primarily to those wishing to port or write new base-table implementations.
All of these functions are accessed through a single procedure by
calling that procedure with the symbol name of the operation. A
procedure will be returned if that operation is supported and #f
otherwise. For example:
(require 'alist-table) (define open-base (alist-table 'make-base)) make-base => *a procedure* (define foo (alist-table 'foo)) foo => #f
#f is returned.
Calling the close-base method on this database and possibly other
operations will cause filename to be written to. If
filename is #f a temporary, non-disk based database will be
created if such can be supported by the base table implelentation.
#t, this database will have methods capable of
effecting change to the database. If mutable? is #f, only
methods for inquiring the database will be available. If the database
cannot be opened as specified #f is returned.
Calling the close-base (and possibly other) method on a
mutable? database will cause filename to be written to.
close-database (and possibly other) method on lldb may
cause filename to be written to. If filename is #f
this database will be changed to a temporary, non-disk based database if
such can be supported by the underlying base table implelentation. If
the operations completed successfully, #t is returned.
Otherwise, #f is returned.
#f, no action is taken and #f is returned. If this
operation completes successfully, #t is returned. Otherwise,
#f is returned.
#t is returned. Otherwise, #f is returned.
#f. The base table can then be opened using (open-table
lldb base-id). The positive integer key-dimension is
the number of keys composed to make a primary-key for this table.
The list of symbols column-types describes the types of each
column.
open-table. catalog-id will be used as the base table for
the system catalog.
#f.
As with make-table, the positive integer key-dimension is
the number of keys composed to make a primary-key for this table.
The list of symbols column-types describes the types of each
column.
#t if the base table associated with base-id was
removed from the low level database lldb, and #f otherwise.
Any 2 arguments of the supported type passed to the returned function
which are not equal? must result in returned values which are not
equal?.
Any 2 lists of supported types (which must at least include symbols and
non-negative integers) passed to the returned function which are not
equal? must result in returned values which are not
equal?.
(make-list-keyifier key-dimension types).
This procedure returns a key which is equal? to the
column-numberth element of the list which was passed to create
combined-key. The list types must have at least
key-dimension elements.
(make-list-keyifier key-dimension types).
This procedure returns a list of keys which are elementwise
equal? to the list which was passed to create combined-key.
In the following functions, the key argument can always be assumed to be the value returned by a call to a keyify routine.
In contrast, a match-key argument is a list of length equal to the number of primary keys. The match-key restricts the actions of the table command to those records whose primary keys all satisfy the corresponding element of the match-key list. The elements and their actions are:
#f- The false value matches any key in the corresponding position.
- an object of type procedure
- This procedure must take a single argument, the key in the corresponding position. Any key for which the procedure returns a non-false value is a match; Any key for which the procedure returns a
#fis not.- other values
- Any other value matches only those keys
equal?to it.
#f value if there is a row associated with
key in the table opened in handle and #f otherwise.
#f otherwise.
#t if symbol names a type allowed as a column value
by the implementation, and #f otherwise. At a minimum, an
implementation must support the types integer, symbol,
string, boolean, and base-id.
#t if symbol names a type allowed as a key value by
the implementation, and #f otherwise. At a minimum, an
implementation must support the types integer, and symbol.
integer
symbol
boolean
#t or #f.
base-id
open-table. The value of catalog-id must be an acceptable
base-id.
(require 'relational-database)
This package implements a database system inspired by the Relational Model (E. F. Codd, A Relational Model of Data for Large Shared Data Banks). An SLIB relational database implementation can be created from any section Base Table implementation.
Most nontrivial programs contain databases: Makefiles, configure scripts, file backup, calendars, editors, source revision control, CAD systems, display managers, menu GUIs, games, parsers, debuggers, profilers, and even error reporting are all rife with databases. Coding databases is such a common activity in programming that many may not be aware of how often they do it.
A database often starts as a dispatch in a program. The author, perhaps because of the need to make the dispatch configurable, the need for correlating dispatch in other routines, or because of changes or growth, devises a data structure to contain the information, a routine for interpreting that data structure, and perhaps routines for augmenting and modifying the stored data. The dispatch must be converted into this form and tested.
The programmer may need to devise an interactive program for enabling easy examination and modification of the information contained in this database. Often, in an attempt to foster modularity and avoid delays in release, intermediate file formats for the database information are devised. It often turns out that users prefer modifying these intermediate files with a text editor to using the interactive program in order to do operations (such as global changes) not forseen by the program's author.
In order to address this need, the concientous software engineer may even provide a scripting language to allow users to make repetitive database changes. Users will grumble that they need to read a large manual and learn yet another programming language (even if it almost has language "xyz" syntax) in order to do simple configuration.
All of these facilities need to be designed, coded, debugged, documented, and supported; often causing what was very simple in concept to become a major developement project.
This view of databases just outlined is somewhat the reverse of the view of the originators of the Relational Model of database abstraction. The relational model was devised to unify and allow interoperation of large multi-user databases running on diverse platforms. A fairly general purpose "Comprehensive Language" for database manipulations is mandated (but not specified) as part of the relational model for databases.
One aspect of the Relational Model of some importance is that the "Comprehensive Language" must be expressible in some form which can be stored in the database. This frees the programmer from having to make programs data-driven in order to use a database.
This package includes as one of its basic supported types Scheme
expressions. This type allows expressions as defined by the
Scheme standards to be stored in the database. Using slib:eval
retrieved expressions can be evaluated (in the top-level environment).
Scheme's lambda facilitates closure of environments, modularity,
etc. so that procedures (which could not be stored directly most
databases) can still be effectively retrieved. Since slib:eval
evaluates expressions in the top-level environment, built-in and user
defined procedures can be easily accessed by name.
This package's purpose is to standardize (through a common interface) database creation and usage in Scheme programs. The relational model's provision for inclusion of language expressions as data as well as the description (in tables, of course) of all of its tables assures that relational databases are powerful enough to assume the roles currently played by thousands of ad-hoc routines and data formats.
Such standardization to a relational-like model brings many benefits:
Returns a procedure implementing a relational database using the base-table-implementation.
All of the operations of a base table implementation are accessed
through a procedure defined by requireing that implementation.
Similarly, all of the operations of the relational database
implementation are accessed through the procedure returned by
make-relational-system. For instance, a new relational database
could be created from the procedure returned by
make-relational-system by:
(require 'alist-table)
(define relational-alist-system
(make-relational-system alist-table))
(define create-alist-database
(relational-alist-system 'create-database))
(define my-database
(create-alist-database "mydata.db"))
What follows are the descriptions of the methods available from
relational system returned by a call to make-relational-system.
Returns an open, nearly empty relational database associated with
filename. The only tables defined are the system catalog and
domain table. Calling the close-database method on this database
and possibly other operations will cause filename to be written
to. If filename is #f a temporary, non-disk based database
will be created if such can be supported by the underlying base table
implelentation. If the database cannot be created as specified
#f is returned. For the fields and layout of descriptor tables,
See section Catalog Representation
Returns an open relational database associated with filename. If
mutable? is #t, this database will have methods capable of
effecting change to the database. If mutable? is #f, only
methods for inquiring the database will be available. Calling the
close-database (and possibly other) method on a mutable?
database will cause filename to be written to. If the database
cannot be opened as specified #f is returned.
These are the descriptions of the methods available from an open relational database. A method is retrieved from a database by calling the database with the symbol name of the operation. For example:
(define my-database
(create-alist-database "mydata.db"))
(define telephone-table-desc
((my-database 'create-table) 'telephone-table-desc))
#t is returned. Otherwise, #f is returned.
close-database (and
possibly other) method on this database will cause filename to be
written to. If filename is #f this database will be
changed to a temporary, non-disk based database if such can be supported
by the underlying base table implelentation. If the operations
completed successfully, #t is returned. Otherwise, #f is
returned.
#t if table-name exists in the system catalog,
otherwise returns #f.
#f.
These methods will be present only in databases which are mutable?.
#f otherwise.
#f. For the fields and layout of descriptor tables,
See section Catalog Representation.
#f.
These are the descriptions of the methods available from an open relational table. A method is retrieved from a table by calling the table with the symbol name of the operation. For example:
(define telephone-table-desc
((my-database 'create-table) 'telephone-table-desc))
(require 'common-list-functions)
(define ndrp (telephone-table-desc 'row:insert))
(ndrp '(1 #t name #f string))
(ndrp '(2 #f telephone
(lambda (d)
(and (string? d) (> (string-length d) 2)
(every
(lambda (c)
(memv c '(#\0 #\1 #\2 #\3 #\4 #\5 #\6 #\7 #\8 #\9
#\+ #\( #\ #\) #\-)))
(string->list d))))
string))
Some operations described below require primary key arguments. Primary keys arguments are denoted key1 key2 .... It is an error to call an operation for a table which takes primary key arguments with the wrong number of primary keys for that table.
The term row used below refers to a Scheme list of values (one for
each column) in the order specified in the descriptor (table) for this
table. Missing values appear as #f. Primary keys must not
be missing.
#f otherwise.
((plat 'get 'processor) 'djgpp) => i386 ((plat 'get 'processor) 'be-os) => #f
((plat 'get* 'processor)) => (i386 8086 i386 8086 i386 i386 8086 m68000 m68000 m68000 m68000 m68000 powerpc) ((plat 'get* 'processor) #f) => (i386 8086 i386 8086 i386 i386 8086 m68000 m68000 m68000 m68000 m68000 powerpc) (define (a-key? key) (char=? #\a (string-ref (symbol->string key) 0))) ((plat 'get* 'processor) a-key?) => (m68000 m68000 m68000 m68000 m68000 powerpc) ((plat 'get* 'name) a-key?) => (atari-st-turbo-c atari-st-gcc amiga-sas/c-5.10 amiga-aztec amiga-dice-c aix)
#f otherwise.
((plat 'row:retrieve) 'linux) => (linux i386 linux gcc) ((plat 'row:retrieve) 'multics) => #f
((plat 'row:retrieve*) a-key?) => ((atari-st-turbo-c m68000 atari turbo-c) (atari-st-gcc m68000 atari gcc) (amiga-sas/c-5.10 m68000 amiga sas/c) (amiga-aztec m68000 amiga aztec) (amiga-dice-c m68000 amiga dice-c) (aix powerpc aix -))
#f otherwise.
Real relational programmers would use some least-upper-bound join for every row to get them in order; But we don't have joins yet.
The (optional) match-key1 ... arguments are used to restrict
actions of a whole-table operation to a subset of that table. Those
procedures (returned by methods) which accept match-key arguments will
accept any number of match-key arguments between zero and the number of
primary keys in the table. Any unspecified match-key arguments
default to #f.
The match-key1 ... restrict the actions of the table command to those records whose primary keys each satisfy the corresponding match-key argument. The arguments and their actions are:
#f- The false value matches any key in the corresponding position.
- an object of type procedure
- This procedure must take a single argument, the key in the corresponding position. Any key for which the procedure returns a non-false value is a match; Any key for which the procedure returns a
#fis not.- other values
- Any other value matches only those keys
equal?to it.
Each database (in an implementation) has a system catalog which describes all the user accessible tables in that database (including itself).
The system catalog base table has the following fields. PRI
indicates a primary key for that table.
PRI table-name
column-limit the highest column number
coltab-name descriptor table name
bastab-id data base table identifier
user-integrity-rule
view-procedure A scheme thunk which, when called,
produces a handle for the view. coltab
and bastab are specified if and only if
view-procedure is not.
Descriptors for base tables (not views) are tables (pointed to by system catalog). Descriptor (base) tables have the fields:
PRI column-number sequential integers from 1
primary-key? boolean TRUE for primary key components
column-name
column-integrity-rule
domain-name
A primary key is any column marked as primary-key? in the
corresponding descriptor table. All the primary-key? columns
must have lower column numbers than any non-primary-key? columns.
Every table must have at least one primary key. Primary keys must be
sufficient to distinguish all rows from each other in the table. All of
the system defined tables have a single primary key.
This package currently supports tables having from 1 to 4 primary keys if there are non-primary columns, and any (natural) number if all columns are primary keys. If you need more than 4 primary keys, I would like to hear what you are doing!
A domain is a category describing the allowable values to occur in a column. It is described by a (base) table with the fields:
PRI domain-name
foreign-table
domain-integrity-rule
type-id
type-param
The type-id field value is a symbol. This symbol may be used by the underlying base table implementation in storing that field.
If the foreign-table field is non-#f then that field names
a table from the catalog. The values for that domain must match a
primary key of the table referenced by the type-param (or
#f, if allowed). This package currently does not support
composite foreign-keys.
The types for which support is planned are:
atom
symbol
string [<length>]
number [<base>]
money <currency>
date-time
boolean
foreign-key <table-name>
expression
virtual <expression>
Although `rdms.scm' is not large, I found it very difficult to write (six rewrites). I am not aware of any other examples of a generalized relational system (although there is little new in CS). I left out several aspects of the Relational model in order to simplify the job. The major features lacking (which might be addressed portably) are views, transaction boundaries, and protection.
Protection needs a model for specifying priveledges. Given how operations are accessed from handles it should not be difficult to restrict table accesses to those allowed for that user.
The system catalog has a field called view-procedure. This
should allow a purely functional implementation of views. This will
work but is unsatisfying for views resulting from a selection
(subset of rows); for whole table operations it will not be possible to
reduce the number of keys scanned over when the selection is specified
only by an opaque procedure.
Transaction boundaries present the most intriguing area. Transaction boundaries are actually a feature of the "Comprehensive Language" of the Relational database and not of the database. Scheme would seem to provide the opportunity for an extremely clean semantics for transaction boundaries since the builtin procedures with side effects are small in number and easily identified.
These side-effect builtin procedures might all be portably redefined to versions which properly handled transactions. Compiled library routines would need to be recompiled as well. Many system extensions (delete-file, system, etc.) would also need to be redefined.
There are 2 scope issues that must be resolved for multiprocess transaction boundaries:
dynamic-wind would
provide a workable hook into process switching for many implementations.
This enhancement wraps a utility layer on relational-database
which provides:
*commands*
table in database.
Also included are utilities which provide:
for any SLIB relational database.
*commands* table)
relational database (with base-table type base-table-type)
associated with filename.
open-database will attempt to deduce the correct
base-table-type. If the database can not be opened or if it lacks the
*commands* table, #f is returned.
The table *commands* in an enhanced relational-database has
the fields (with domains):
PRI name symbol
parameters parameter-list
procedure expression
documentation string
The parameters field is a foreign key (domain
parameter-list) of the *catalog-data* table and should
have the value of a table described by *parameter-columns*. This
parameter-list table describes the arguments suitable for passing
to the associated command. The intent of this table is to be of a form
such that different user-interfaces (for instance, pull-down menus or
plain-text queries) can operate from the same table. A
parameter-list table has the following fields:
PRI index uint
name symbol
arity parameter-arity
domain domain
defaulter expression
expander expression
documentation string
The arity field can take the values:
single
optional
boolean
#f
is substituted) is acceptable.
nary
nary1
The domain field specifies the domain which a parameter or
parameters in the indexth field must satisfy.
The defaulter field is an expression whose value is either
#f or a procedure of one argument (the parameter-list) which
returns a list of the default value or values as appropriate.
Note that since the defaulter procedure is called every time a
default parameter is needed for this column, sticky defaults can
be implemented using shared state with the domain-integrity-rule.
When an enhanced relational-database is called with a symbol which
matches a name in the *commands* table, the associated
procedure expression is evaluated and applied to the enhanced
relational-database. A procedure should then be returned which the user
can invoke on (optional) arguments.
The command *initialize* is special. If present in the
*commands* table, open-database or open-database!
will return the value of the *initialize* command. Notice that
arbitrary code can be run when the *initialize* procedure is
automatically applied to the enhanced relational-database.
Note also that if you wish to shadow or hide from the user
relational-database methods described in section Relational Database Operations, this can be done by a dispatch in the closure returned by
the *initialize* expression rather than by entries in the
*commands* table if it is desired that the underlying methods
remain accessible to code in the *commands* table.
name field of the command's parameter-table.
index field of the command's parameter-table.
arity field of the command's parameter-table. For a
description of arity see table above.
type-id field of the contents of the domain of the
command's parameter-table.
defaulters field of the command's parameter-table.
nary arity
parameters.
(alias parameter-name). There can be
more than one alias per parameter-name.
For information about parameters, See section Parameter lists. Here is an
example of setting up a command with arguments and parsing those
arguments from a getopt style argument list (see section Getopt).
(require 'database-utilities)
(require 'fluid-let)
(require 'parameters)
(require 'getopt)
(define my-rdb (create-database #f 'alist-table))
(define-tables my-rdb
'(foo-params
*parameter-columns*
*parameter-columns*
((1 single-string single string
(lambda (pl) '("str")) #f "single string")
(2 nary-symbols nary symbol
(lambda (pl) '()) #f "zero or more symbols")
(3 nary1-symbols nary1 symbol
(lambda (pl) '(symb)) #f "one or more symbols")
(4 optional-number optional uint
(lambda (pl) '()) #f "zero or one number")
(5 flag boolean boolean
(lambda (pl) '(#f)) #f "a boolean flag")))
'(foo-pnames
((name string))
((parameter-index uint))
(("s" 1)
("single-string" 1)
("n" 2)
("nary-symbols" 2)
("N" 3)
("nary1-symbols" 3)
("o" 4)
("optional-number" 4)
("f" 5)
("flag" 5)))
'(my-commands
((name symbol))
((parameters parameter-list)
(parameter-names parameter-name-translation)
(procedure expression)
(documentation string))
((foo
foo-params
foo-pnames
(lambda (rdb) (lambda args (print args)))
"test command arguments"))))
(define (dbutil:serve-command-line rdb command-table
command argc argv)
(set! argv (if (vector? argv) (vector->list argv) argv))
((make-command-server rdb command-table)
command
(lambda (comname comval options positions
arities types defaulters dirs aliases)
(apply comval (getopt->arglist
argc argv options positions
arities types defaulters dirs aliases)))))
(define (cmd . opts)
(fluid-let ((*optind* 1))
(printf "%-34s => "
(call-with-output-string (lambda (pt) (write (cons 'cmd opts) pt)))
;;(apply string-append (map (lambda (x) (string-append x " ")) opts))
)
(set! opts (cons "cmd" opts))
(force-output)
(dbutil:serve-command-line
my-rdb 'my-commands 'foo (length opts) opts)))
(cmd) => ("str" () (symb) () #f)
(cmd "-f") => ("str" () (symb) () #t)
(cmd "--flag") => ("str" () (symb) () #t)
(cmd "-o177") => ("str" () (symb) (177) #f)
(cmd "-o" "177") => ("str" () (symb) (177) #f)
(cmd "--optional" "621") => ("str" () (symb) (621) #f)
(cmd "--optional=621") => ("str" () (symb) (621) #f)
(cmd "-s" "speciality") => ("speciality" () (symb) () #f)
(cmd "-sspeciality") => ("speciality" () (symb) () #f)
(cmd "--single" "serendipity") => ("serendipity" () (symb) () #f)
(cmd "--single=serendipity") => ("serendipity" () (symb) () #f)
(cmd "-n" "gravity" "piety") => ("str" () (piety gravity) () #f)
(cmd "-ngravity" "piety") => ("str" () (piety gravity) () #f)
(cmd "--nary" "chastity") => ("str" () (chastity) () #f)
(cmd "--nary=chastity" "") => ("str" () ( chastity) () #f)
(cmd "-N" "calamity") => ("str" () (calamity) () #f)
(cmd "-Ncalamity") => ("str" () (calamity) () #f)
(cmd "--nary1" "surety") => ("str" () (surety) () #f)
(cmd "--nary1=surety") => ("str" () (surety) () #f)
(cmd "-N" "levity" "fealty") => ("str" () (fealty levity) () #f)
(cmd "-Nlevity" "fealty") => ("str" () (fealty levity) () #f)
(cmd "--nary1" "surety" "brevity") => ("str" () (brevity surety) () #f)
(cmd "--nary1=surety" "brevity") => ("str" () (brevity surety) () #f)
(cmd "-?")
-|
Usage: cmd [OPTION ARGUMENT ...] ...
-f, --flag
-o, --optional[=]<number>
-n, --nary[=]<symbols> ...
-N, --nary1[=]<symbols> ...
-s, --single[=]<string>
ERROR: getopt->parameter-list "unrecognized option" "-?"
Some commands are defined in all extended relational-databases. The are called just like section Relational Database Operations.
(car domain-row) and
returns #t. Otherwise returns #f.
For the fields and layout of the domain table, See section Catalog Representation. Currently, these fields are
The following example adds 3 domains to the `build' database.
`Optstring' is either a string or #f. filename is a
string and build-whats is a symbol.
(for-each (build 'add-domain)
'((optstring #f
(lambda (x) (or (not x) (string? x)))
string
#f)
(filename #f #f string #f)
(build-whats #f #f symbol #f)))
(<name> <descriptor-name> <descriptor-name> <rows>)
or
(<name> <primary-key-fields> <other-fields> <rows>)
where <name> is the table name, <descriptor-name> is the symbol name of a descriptor table, <primary-key-fields> and <other-fields> describe the primary keys and other fields respectively, and <rows> is a list of data rows to be added to the table.
<primary-key-fields> and <other-fields> are lists of field descriptors of the form:
(<column-name> <domain>)
or
(<column-name> <domain> <column-integrity-rule>)
where <column-name> is the column name, <domain> is the domain
of the column, and <column-integrity-rule> is an expression whose
value is a procedure of one argument (which returns #f to signal
an error).
If <domain> is not a defined domain name and it matches the name of this table or an already defined (in one of spec-0 ...) single key field table, a foriegn-key domain will be created for it.
*reports* in the relational database rdb.
destination is a port, string, or symbol. If destination is
a:
Each row in the table *reports* has the fields:
format string. At the beginning and end of each page
respectively, format is called with this string and the (list of)
column-names of this table.
format string. For each row in the table, format is
called with this string and the row.
0 if a row's lines should not be broken over page
boundaries.
Each row in the table *printers* has the fields:
The report is prepared as follows:
Format (see section Format (version 3.0)) is called with the header field
and the (list of) column-names of the table.
Format is called with the reporter field and (on
successive calls) each record in the natural order for the table. A
count is kept of the number of newlines output by format. When the
number of newlines to be output exceeds the number of lines per page,
the set of lines will be broken if there are more than
minimum-break left on this page and the number of lines for this
row is larger or equal to twice minimum-break.
Format is called with the footer field and the (list of)
column-names of the table. The footer field should not output a
newline.
The following example shows a new database with the name of `foo.db' being created with tables describing processor families and processor/os/compiler combinations.
The database command define-tables is defined to call
define-tables with its arguments. The database is also
configured to print `Welcome' when the database is opened. The
database is then closed and reopened.
(require 'database-utilities)
(define my-rdb (create-database "foo.db" 'alist-table))
(define-tables my-rdb
'(*commands*
((name symbol))
((parameters parameter-list)
(procedure expression)
(documentation string))
((define-tables
no-parameters
no-parameter-names
(lambda (rdb) (lambda specs (apply define-tables rdb specs)))
"Create or Augment tables from list of specs")
(*initialize*
no-parameters
no-parameter-names
(lambda (rdb) (display "Welcome") (newline) rdb)
"Print Welcome"))))
((my-rdb 'define-tables)
'(processor-family
((family atom))
((also-ran processor-family))
((m68000 #f)
(m68030 m68000)
(i386 8086)
(8086 #f)
(powerpc #f)))
'(platform
((name symbol))
((processor processor-family)
(os symbol)
(compiler symbol))
((aix powerpc aix -)
(amiga-dice-c m68000 amiga dice-c)
(amiga-aztec m68000 amiga aztec)
(amiga-sas/c-5.10 m68000 amiga sas/c)
(atari-st-gcc m68000 atari gcc)
(atari-st-turbo-c m68000 atari turbo-c)
(borland-c-3.1 8086 ms-dos borland-c)
(djgpp i386 ms-dos gcc)
(linux i386 linux gcc)
(microsoft-c 8086 ms-dos microsoft-c)
(os/2-emx i386 os/2 gcc)
(turbo-c-2 8086 ms-dos turbo-c)
(watcom-9.0 i386 ms-dos watcom))))
((my-rdb 'close-database))
(set! my-rdb (open-database "foo.db" 'alist-table))
-|
Welcome
Balanced binary trees are a useful data structure for maintaining large sets of ordered objects or sets of associations whose keys are ordered. MIT Scheme has an comprehensive implementation of weight-balanced binary trees which has several advantages over the other data structures for large aggregates:
(+ 1 x)
modifies neither the constant 1 nor the value bound to x. The
trees are referentially transparent thus the programmer need not worry
about copying the trees. Referential transparency allows space
efficiency to be achieved by sharing subtrees.
These features make weight-balanced trees suitable for a wide range of applications, especially those that require large numbers of sets or discrete maps. Applications that have a few global databases and/or concentrate on element-level operations like insertion and lookup are probably better off using hash-tables or red-black trees.
The size of a tree is the number of associations that it contains. Weight balanced binary trees are balanced to keep the sizes of the subtrees of each node within a constant factor of each other. This ensures logarithmic times for single-path operations (like lookup and insertion). A weight balanced tree takes space that is proportional to the number of associations in the tree. For the current implementation, the constant of proportionality is six words per association.
Weight balanced trees can be used as an implementation for either
discrete sets or discrete maps (associations). Sets are implemented by
ignoring the datum that is associated with the key. Under this scheme
if an associations exists in the tree this indicates that the key of the
association is a member of the set. Typically a value such as
(), #t or #f is associated with the key.
Many operations can be viewed as computing a result that, depending on
whether the tree arguments are to
thhe arities of each parameter. Corresponds to the
arity field of the command's parameter-table. For a
description of arity see table above.
type-id field of the contents of the domain of the
command's parameter-table.
defaulters field of the command's parameter-table.
nary arity
parameters.
(alias parameter-name). There can be
more than one alias per parameter-name.
For information about parameters, See section Parameter lists. Here is an
example of setting up a command with arguments and parsing those
arguments from a getopt style argument list (see section Getopt).
(require 'database-utilities)
(require 'fluid-let)
(require 'parameters)
(require 'getopt)
(define my-rdb (create-database #f 'alist-table))
(define-tables my-rdb
'(foo-params
*parameter-columns*
*parameter-columns*
((1 single-string single string
(lambda (pl) '("str")) #f "single string")
(2 nary-symbols nary symbol
(lambda (pl) '()) #f "zero or more symbols")
(3 nary1-symbols nary1 symbol
(lambda (pl) '(symb)) #f "one or more symbols")
(4 optional-number optional uint
(lambda (pl) '()) #f "zero or one number")
(5 flag boolean boolean
(lambda (pl) '(#f)) #f "a boolean flag")))
'(foo-pnames
((name string))
((parameter-index uint))
(("s" 1)
("single-string" 1)
("n" 2)
("nary-symbols" 2)
("N" 3)
("nary1-symbols" 3)
("o" 4)
("optional-number" 4)
("f" 5)
("flag" 5)))
'(my-commands
((name symbol))
((parameters parameter-list)
(parameter-names parameter-name-translation)
(procedure expression)
(documentation string))
((foo
foo-params
foo-pnames
(lambda (rdb) (lambda args (print args)))
"test command arguments"))))
(define (dbutil:serve-command-line rdb command-table
command argc argv)
(set! argv (if (vector? argv) (vector->list argv) argv))
((make-command-server rdb command-table)
command
(lambda (comname comval options positions
arities types defaulters dirs aliases)
(apply comval (getopt->arglist
argc argv options positions
arities types defaulters dirs aliases)))))
(define (cmd . opts)
(fluid-let ((*optind* 1))
(printf "%-34s => "
(call-with-output-string (lambda (pt) (write (cons 'cmd opts) pt)))
;;(apply string-append (map (lambda (x) (string-append x " ")) opts))
)
(set! opts (cons "cmd" opts))
(force-output)
(dbutil:serve-command-line
my-rdb 'my-commands 'foo (length opts) opts)))
(cmd) => ("str" () (symb) () #f)
(cmd "-f") => ("str" () (symb) () #t)
(cmd "--flag") => ("str" () (symb) () #t)
(cmd "-o177") => ("str" () (symb) (177) #f)
(cmd "-o" "177") => ("str" () (symb) (177) #f)
(cmd "--optional" "621") => ("str" () (symb) (621) #f)
(cmd "--optional=621") => ("str" () (symb) (621) #f)
(cmd "-s" "speciality") => ("speciality" () (symb) () #f)
(cmd "-sspeciality") => ("speciality" () (symb) () #f)
(cmd "--single" "serendipity") => ("serendipity" () (symb) () #f)
(cmd "--single=serendipity") => ("serendipity" () (symb) () #f)
(cmd "-n" "gravity" "piety") => ("str" () (piety gravity) () #f)
(cmd "-ngravity" "piety") => ("str" () (piety gravity) () #f)
(cmd "--nary" "chastity") => ("str" () (chastity) () #f)
(cmd "--nary=chastity" "") => ("str" () ( chastity) () #f)
(cmd "-N" "calamity") => ("str" () (calamity) () #f)
(cmd "-Ncalamity") => ("str" () (calamity) () #f)
(cmd "--nary1" "surety") => ("str" () (surety) () #f)
(cmd "--nary1=surety") => ("str" () (surety) () #f)
(cmd "-N" "levity" "fealty") => ("str" () (fealty levity) () #f)
(cmd "-Nlevity" "fealty") => ("str" () (fealty levity) () #f)
(cmd "--nary1" "surety" "brevity") => ("str" () (brevity surety) () #f)
(cmd "--nary1=surety" "brevity") => ("str" () (brevity surety) () #f)
(cmd "-?")
-|
Usage: cmd [OPTION ARGUMENT ...] ...
-f, --flag
-o, --optional[=]<number>
-n, --nary[=]<symbols> ...
-N, --nary1[=]<symbols> ...
-s, --single[=]<string>
ERROR: getopt->parameter-list "unrecognized option" "-?"
Some commands are defined in all extended relational-databases. The are called just like section Relational Database Operations.
(car domain-row) and
returns #t. Otherwise returns #f.
For the fields and layout of the domain table, See section Catalog Representation. Currently, these fields are
The following example adds 3 domains to the `build' database.
`Optstring' is either a string or #f. filename is a
string and build-whats is a symbol.
(for-each (build 'add-domain)
'((optstring #f
(lambda (x) (or (not x) (string? x)))
string
#f)
(filename #f #f string #f)
(build-whats #f #f symbol #f)))
(<name> <descriptor-name> <descriptor-name> <rows>)
or
(<name> <primary-key-fields> <other-fields> <rows>)
where <name> is the table name, <descriptor-name> is the symbol name of a descriptor table, <primary-key-fields> and <other-fields> describe the primary keys and other fields respectively, and <rows> is a list of data rows to be added to the table.
<primary-key-fields> and <other-fields> are lists of field descriptors of the form:
(<column-name> <domain>)
or
(<column-name> <domain> <column-integrity-rule>)
where <column-name> is the column name, <domain> is the domain
of the column, and <column-integrity-rule> is an expression whose
value is a procedure of one argument (which returns #f to signal
an error).
If <domain> is not a defined domain name and it matches the name of this table or an already defined (in one of spec-0 ...) single key field table, a foriegn-key domain will be created for it.
*reports* in the relational database rdb.
destination is a port, string, or symbol. If destination is
a:
Each row in the table *reports* has the fields:
format string. At the beginning and end of each page
respectively, format is called with this string and the (list of)
column-names of this table.
format string. For each row in the table, format is
called with this string and the row.
0 if a row's lines should not be broken over page
boundaries.
Each row in the table *printers* has the fields:
The report is prepared as follows:
Format (see section Format (version 3.0)) is called with the header field
and the (list of) column-names of the table.
Format is called with the reporter field and (on
successive calls) each record in the natural order for the table. A
count is kept of the number of newlines output by format. When the
number of newlines to be output exceeds the number of lines per page,
the set of lines will be broken if there are more than
minimum-break left on this page and the number of lines for this
row is larger or equal to twice minimum-break.
Format is called with the footer field and the (list of)
column-names of the table. The footer field should not output a
newline.
The following example shows a new database with the name of `foo.db' being created with tables describing processor families and processor/os/compiler combinations.
The database command define-tables is defined to call
define-tables with its arguments. The database is also
configured to print `Welcome' when the database is opened. The
database is then closed and reopened.
(require 'database-utilities)
(define my-rdb (create-database "foo.db" 'alist-table))
(define-tables my-rdb
'(*commands*
((name symbol))
((parameters parameter-list)
(procedure expression)
(documentation string))
((define-tables
no-parameters
no-parameter-names
(lambda (rdb) (lambda specs (apply define-tables rdb specs)))
"Create or Augment tables from list of specs")
(*initialize*
no-parameters
no-parameter-names
(lambda (rdb) (display "Welcome") (newline) rdb)
"Print Welcome"))))
((my-rdb 'define-tables)
'(processor-family
((family atom))
((also-ran processor-family))
((m68000 #f)
(m68030 m68000)
(i386 8086)
(8086 #f)
(powerpc #f)))
'(platform
((name symbol))
((processor processor-family)
(os symbol)
(compiler symbol))
((aix powerpc aix -)
(amiga-dice-c m68000 amiga dice-c)
(amiga-aztec m68000 amiga aztec)
(amiga-sas/c-5.10 m68000 amiga sas/c)
(atari-st-gcc m68000 atari gcc)
(atari-st-turbo-c m68000 atari turbo-c)
(borland-c-3.1 8086 ms-dos borland-c)
(djgpp i386 ms-dos gcc)
(linux i386 linux gcc)
(microsoft-c 8086 ms-dos microsoft-c)
(os/2-emx i386 os/2 gcc)
(turbo-c-2 8086 ms-dos turbo-c)
(watcom-9.0 i386 ms-dos watcom))))
((my-rdb 'close-database))
(set! my-rdb (open-database "foo.db" 'alist-table))
-|
Welcome
Balanced binary trees are a useful data structure for maintaining large sets of ordered objects or sets of associations whose keys are ordered. MIT Scheme has an comprehensive implementation of weight-balanced binary trees which has several advantages over the other data structures for large aggregates:
(+ 1 x)
modifies neither the constant 1 nor the value bound to x. The
trees are referentially transparent thus the programmer need not worry
about copying the trees. Referential transparency allows space
efficiency to be achieved by sharing subtrees.
These features make weight-balanced trees suitable for a wide range of applications, especially those that require large numbers of sets or discrete maps. Applications that have a few global databases and/or concentrate on element-level operations like insertion and lookup are probably better off using hash-tables or red-black trees.
The size of a tree is the number of associations that it contains. Weight balanced binary trees are balanced to keep the sizes of the subtrees of each node within a constant factor of each other. This ensures logarithmic times for single-path operations (like lookup and insertion). A weight balanced tree takes space that is proportional to the number of associations in the tree. For the current implementation, the constant of proportionality is six words per association.
Weight balanced trees can be used as an implementation for either
discrete sets or discrete maps (associations). Sets are implemented by
ignoring the datum that is associated with the key. Under this scheme
if an associations exists in the tree this indicates that the key of the
association is a member of the set. Typically a value such as
(), #t or #f is associated with the key.
Many operations can be viewed as computing a result that, depending on
whether the tree arguments are to
thhe arities of each parameter. Corresponds to the
arity field of the command's parameter-table. For a
description of arity see table above.
type-id field of the contents of the domain of the
command's parameter-table.
defaulters field of the command's parameter-table.
nary arity
parameters.
(alias parameter-name). There can be
more than one alias per parameter-name.
For information about parameters, See section Parameter lists. Here is an
example of setting up a command with arguments and parsing those
arguments from a getopt style argument list (see section Getopt).
(require 'database-utilities)
(require 'fluid-let)
(require 'parameters)
(require 'getopt)
(define my-rdb (create-database #f 'alist-table))
(define-tables my-rdb
'(foo-params
*parameter-columns*
*parameter-columns*
((1 single-string single string
(lambda (pl) '("str")) #f "single string")
(2 nary-symbols nary symbol
(lambda (pl) '()) #f "zero or more symbols")
(3 nary1-symbols nary1 symbol
(lambda (pl) '(symb)) #f "one or more symbols")
(4 optional-number optional uint
(lambda (pl) '()) #f "zero or one number")
(5 flag boolean boolean
(lambda (pl) '(#f)) #f "a boolean flag")))
'(foo-pnames
((name string))
((parameter-index uint))
(("s" 1)
("single-string" 1)
("n" 2)
("nary-symbols" 2)
("N" 3)
("nary1-symbols" 3)
("o" 4)
("optional-number" 4)
("f" 5)
("flag" 5)))
'(my-commands
((name symbol))
((parameters parameter-list)
(parameter-names parameter-name-translation)
(procedure expression)
(documentation string))
((foo
foo-params
foo-pnames
(lambda (rdb) (lambda args (print args)))
"test command arguments"))))
(define (dbutil:serve-command-line rdb command-table
command argc argv)
(set! argv (if (vector? argv) (vector->list argv) argv))
((make-command-server rdb command-table)
command
(lambda (comname comval options positions
arities types defaulters dirs aliases)
(apply comval (getopt->arglist
argc argv options positions
arities types defaulters dirs aliases)))))
(define (cmd . opts)
(fluid-let ((*optind* 1))
(printf "%-34s => "
(call-with-output-string (lambda (pt) (write (cons 'cmd opts) pt)))
;;(apply string-append (map (lambda (x) (string-append x " ")) opts))
)
(set! opts (cons "cmd" opts))
(force-output)
(dbutil:serve-command-line
my-rdb 'my-commands 'foo (length opts) opts)))
(cmd) => ("str" () (symb) () #f)
(cmd "-f") => ("str" () (symb) () #t)
(cmd "--flag") => ("str" () (symb) () #t)
(cmd "-o177") => ("str" () (symb) (177) #f)
(cmd "-o" "177") => ("str" () (symb) (177) #f)
(cmd "--optional" "621") => ("str" () (symb) (621) #f)
(cmd "--optional=621") => ("str" () (symb) (621) #f)
(cmd "-s" "speciality") => ("speciality" () (symb) () #f)
(cmd "-sspeciality") => ("speciality" () (symb) () #f)
(cmd "--single" "serendipity") => ("serendipity" () (symb) () #f)
(cmd "--single=serendipity") => ("serendipity" () (symb) () #f)
(cmd "-n" "gravity" "piety") => ("str" () (piety gravity) () #f)
(cmd "-ngravity" "piety") => ("str" () (piety gravity) () #f)
(cmd "--nary" "chastity") => ("str" () (chastity) () #f)
(cmd "--nary=chastity" "") => ("str" () ( chastity) () #f)
(cmd "-N" "calamity") => ("str" () (calamity) () #f)
(cmd "-Ncalamity") => ("str" () (calamity) () #f)
(cmd "--nary1" "surety") => ("str" () (surety) () #f)
(cmd "--nary1=surety") => ("str" () (surety) () #f)
(cmd "-N" "levity" "fealty") => ("str" () (fealty levity) () #f)
(cmd "-Nlevity" "fealty") => ("str" () (fealty levity) () #f)
(cmd "--nary1" "surety" "brevity") => ("str" () (brevity surety) () #f)
(cmd "--nary1=surety" "brevity") => ("str" () (brevity surety) () #f)
(cmd "-?")
-|
Usage: cmd [OPTION ARGUMENT ...] ...
-f, --flag
-o, --optional[=]<number>
-n, --nary[=]<symbols> ...
-N, --nary1[=]<symbols> ...
-s, --single[=]<string>
ERROR: getopt->parameter-list "unrecognized option" "-?"
Some commands are defined in all extended relational-databases. The are called just like section Relational Database Operations.
(car domain-row) and
returns #t. Otherwise returns #f.
For the fields and layout of the domain table, See section Catalog Representation. Currently, these fields are
The following example adds 3 domains to the `build' database.
`Optstring' is either a string or #f. filename is a
string and build-whats is a symbol.
(for-each (build 'add-domain)
'((optstring #f
(lambda (x) (or (not x) (string? x)))
string
#f)
(filename #f #f string #f)
(build-whats #f #f symbol #f)))
(<name> <descriptor-name> <descriptor-name> <rows>)
or
(<name> <primary-key-fields> <other-fields> <rows>)
where <name> is the table name, <descriptor-name> is the symbol name of a descriptor table, <primary-key-fields> and <other-fields> describe the primary keys and other fields respectively, and <rows> is a list of data rows to be added to the table.
<primary-key-fields> and <other-fields> are lists of field descriptors of the form:
(<column-name> <domain>)
or
(<column-name> <domain> <column-integrity-rule>)
where <column-name> is the column name, <domain> is the domain
of the column, and <column-integrity-rule> is an expression whose
value is a procedure of one argument (which returns #f to signal
an error).
If <domain> is not a defined domain name and it matches the name of this table or an already defined (in one of spec-0 ...) single key field table, a foriegn-key domain will be created for it.
*reports* in the relational database rdb.
destination is a port, string, or symbol. If destination is
a:
Each row in the table *reports* has the fields:
format string. At the beginning and end of each page
respectively, format is called with this string and the (list of)
column-names of this table.
format string. For each row in the table, format is
called with this string and the row.
0 if a row's lines should not be broken over page
boundaries.
Each row in the table *printers* has the fields:
The report is prepared as follows:
Format (see section Format (version 3.0)) is called with the header field
and the (list of) column-names of the table.
Format is called with the reporter field and (on
successive calls) each record in the natural order for the table. A
count is kept of the number of newlines output by format. When the
number of newlines to be output exceeds the number of lines per page,
the set of lines will be broken if there are more than
minimum-break left on this page and the number of lines for this
row is larger or equal to twice minimum-break.
Format is called with the footer field and the (list of)
column-names of the table. The footer field should not output a
newline.
The following example shows a new database with the name of `foo.db' being created with tables describing processor families and processor/os/compiler combinations.
The database command define-tables is defined to call
define-tables with its arguments. The database is also
configured to print `Welcome' when the database is opened. The
database is then closed and reopened.
(require 'database-utilities)
(define my-rdb (create-database "foo.db" 'alist-table))
(define-tables my-rdb
'(*commands*
((name symbol))
((parameters parameter-list)
(procedure expression)
(documentation string))
((define-tables
no-parameters
no-parameter-names
(lambda (rdb) (lambda specs (apply define-tables rdb specs)))
"Create or Augment tables from list of specs")
(*initialize*
no-parameters
no-parameter-names
(lambda (rdb) (display "Welcome") (newline) rdb)
"Print Welcome"))))
((my-rdb 'define-tables)
'(processor-family
((family atom))
((also-ran processor-family))
((m68000 #f)
(m68030 m68000)
(i386 8086)
(8086 #f)
(powerpc #f)))
'(platform
((name symbol))
((processor processor-family)
(os symbol)
(compiler symbol))
((aix powerpc aix -)
(amiga-dice-c m68000 amiga dice-c)
(amiga-aztec m68000 amiga aztec)
(amiga-sas/c-5.10 m68000 amiga sas/c)
(atari-st-gcc m68000 atari gcc)
(atari-st-turbo-c m68000 atari turbo-c)
(borland-c-3.1 8086 ms-dos borland-c)
(djgpp i386 ms-dos gcc)
(linux i386 linux gcc)
(microsoft-c 8086 ms-dos microsoft-c)
(os/2-emx i386 os/2 gcc)
(turbo-c-2 8086 ms-dos turbo-c)
(watcom-9.0 i386 ms-dos watcom))))
((my-rdb 'close-database))
(set! my-rdb (open-database "foo.db" 'alist-table))
-|
Welcome
Balanced binary trees are a useful data structure for maintaining large sets of ordered objects or sets of associations whose keys are ordered. MIT Scheme has an comprehensive implementation of weight-balanced binary trees which has several advantages over the other data structures for large aggregates:
(+ 1 x)
modifies neither the constant 1 nor the value bound to x. The
trees are referentially transparent thus the programmer need not worry
about copying the trees. Referential transparency allows space
efficiency to be achieved by sharing subtrees.
These features make weight-balanced trees suitable for a wide range of applications, especially those that require large numbers of sets or discrete maps. Applications that have a few global databases and/or concentrate on element-level operations like insertion and lookup are probably better off using hash-tables or red-black trees.
The size of a tree is the number of associations that it contains. Weight balanced binary trees are balanced to keep the sizes of the subtrees of each node within a constant factor of each other. This ensures logarithmic times for single-path operations (like lookup and insertion). A weight balanced tree takes space that is proportional to the number of associations in the tree. For the current implementation, the constant of proportionality is six words per association.
Weight balanced trees can be used as an implementation for either
discrete sets or discrete maps (associations). Sets are implemented by
ignoring the datum that is associated with the key. Under this scheme
if an associations exists in the tree this indicates that the key of the
association is a member of the set. Typically a value such as
(), #t or #f is associated with the key.
Many operations can be viewed as computing a result that, depending on
whether the tree arguments are to
thhe arities of each parameter. Corresponds to the
arity field of the command's parameter-table. For a
description of arity see table above.
type-id field of the contents of the domain of the
command's parameter-table.
defaulters field of the command's parameter-table.
nary arity
parameters.
(alias parameter-name). There can be
more than one alias per parameter-name.
For information about parameters, See section Parameter lists. Here is an
example of setting up a command with arguments and parsing those
arguments from a getopt style argument list (see section Getopt).
(require 'database-utilities)
(require 'fluid-let)
(require 'parameters)
(require 'getopt)
(define my-rdb (create-database #f 'alist-table))
(define-tables my-rdb
'(foo-params
*parameter-columns*
*parameter-columns*
((1 single-string single string
(lambda (pl) '("str")) #f "single string")
(2 nary-symbols nary symbol
(lambda (pl) '()) #f "zero or more symbols")
(3 nary1-symbols nary1 symbol
(lambda (pl) '(symb)) #f "one or more symbols")
(4 optional-number optional uint
(lambda (pl) '()) #f "zero or one number")
(5 flag boolean boolean
(lambda (pl) '(#f)) #f "a boolean flag")))
'(foo-pnames
((name string))
((parameter-index uint))
(("s" 1)
("single-string" 1)
("n" 2)
("nary-symbols" 2)
("N" 3)
("nary1-symbols" 3)
("o" 4)
("optional-number" 4)
("f" 5)
("flag" 5)))
'(my-commands
((name symbol))
((parameters parameter-list)
(parameter-names parameter-name-translation)
(procedure expression)
(documentation string))
((foo
foo-params
foo-pnames
(lambda (rdb) (lambda args (print args)))
"test command arguments"))))
(define (dbutil:serve-command-line rdb command-table
command argc argv)
(set! argv (if (vector? argv) (vector->list argv) argv))
((make-command-server rdb command-table)
command
(lambda (comname comval options positions
arities types defaulters dirs aliases)
(apply comval (getopt->arglist
argc argv options positions
arities types defaulters dirs aliases)))))
(define (cmd . opts)
(fluid-let ((*optind* 1))
(printf "%-34s => "
(call-with-output-string (lambda (pt) (write (cons 'cmd opts) pt)))
;;(apply string-append (map (lambda (x) (string-append x " ")) opts))
)
(set! opts (cons "cmd" opts))
(force-output)
(dbutil:serve-command-line
my-rdb 'my-commands 'foo (length opts) opts)))
(cmd) => ("str" () (symb) () #f)
(cmd "-f") => ("str" () (symb) () #t)
(cmd "--flag") => ("str" () (symb) () #t)
(cmd "-o177") => ("str" () (symb) (177) #f)
(cmd "-o" "177") => ("str" () (symb) (177) #f)
(cmd "--optional" "621") => ("str" () (symb) (621) #f)
(cmd "--optional=621") => ("str" () (symb) (621) #f)
(cmd "-s" "speciality") => ("speciality" () (symb) () #f)
(cmd "-sspeciality") => ("speciality" () (symb) () #f)
(cmd "--single" "serendipity") => ("serendipity" () (symb) () #f)
(cmd "--single=serendipity") => ("serendipity" () (symb) () #f)
(cmd "-n" "gravity" "piety") => ("str" () (piety gravity) () #f)
(cmd "-ngravity" "piety") => ("str" () (piety gravity) () #f)
(cmd "--nary" "chastity") => ("str" () (chastity) () #f)
(cmd "--nary=chastity" "") => ("str" () ( chastity) () #f)
(cmd "-N" "calamity") => ("str" () (calamity) () #f)
(cmd "-Ncalamity") => ("str" () (calamity) () #f)
(cmd "--nary1" "surety") => ("str" () (surety) () #f)
(cmd "--nary1=surety") => ("str" () (surety) () #f)
(cmd "-N" "levity" "fealty") => ("str" () (fealty levity) () #f)
(cmd "-Nlevity" "fealty") => ("str" () (fealty levity) () #f)
(cmd "--nary1" "surety" "brevity") => ("str" () (brevity surety) () #f)
(cmd "--nary1=surety" "brevity") => ("str" () (brevity surety) () #f)
(cmd "-?")
-|
Usage: cmd [OPTION ARGUMENT ...] ...
-f, --flag
-o, --optional[=]<number>
-n, --nary[=]<symbols> ...
-N, --nary1[=]<symbols> ...
-s, --single[=]<string>
ERROR: getopt->parameter-list "unrecognized option" "-?"
Some commands are defined in all extended relational-databases. The are called just like section Relational Database Operations.
(car domain-row) and
returns #t. Otherwise returns #f.
For the fields and layout of the domain table, See section Catalog Representation. Currently, these fields are
The following example adds 3 domains to the `build' database.
`Optstring' is either a string or #f. filename is a
string and build-whats is a symbol.
(for-each (build 'add-domain)
'((optstring #f
(lambda (x) (or (not x) (string? x)))
string
#f)
(filename #f #f string #f)
(build-whats #f #f symbol #f)))
(<name> <descriptor-name> <descriptor-name> <rows>)
or
(<name> <primary-key-fields> <other-fields> <rows>)
where <name> is the table name, <descriptor-name> is the symbol name of a descriptor table, <primary-key-fields> and <other-fields> describe the primary keys and other fields respectively, and <rows> is a list of data rows to be added to the table.
<primary-key-fields> and <other-fields> are lists of field descriptors of the form:
(<column-name> <domain>)
or
(<column-name> <domain> <column-integrity-rule>)
where <column-name> is the column name, <domain> is the domain
of the column, and <column-integrity-rule> is an expression whose
value is a procedure of one argument (which returns #f to signal
an error).
If <domain> is not a defined domain name and it matches the name of this table or an already defined (in one of spec-0 ...) single key field table, a foriegn-key domain will be created for it.
*reports* in the relational database rdb.
destination is a port, string, or symbol. If destination is
a:
Each row in the table *reports* has the fields:
format string. At the beginning and end of each page
respectively, format is called with this string and the (list of)
column-names of this table.
format string. For each row in the table, format is
called with this string and the row.
0 if a row's lines should not be broken over page
boundaries.
Each row in the table *printers* has the fields:
The report is prepared as follows:
Format (see section Format (version 3.0)) is called with the header field
and the (list of) column-names of the table.
Format is called with the reporter field and (on
successive calls) each record in the natural order for the table. A
count is kept of the number of newlines output by format. When the
number of newlines to be output exceeds the number of lines per page,
the set of lines will be broken if there are more than
minimum-break left on this page and the number of lines for this
row is larger or equal to twice minimum-break.
Format is called with the footer field and the (list of)
column-names of the table. The footer field should not output a
newline.
The following example shows a new database with the name of `foo.db' being created with tables describing processor families and processor/os/compiler combinations.
The database command define-tables is defined to call
define-tables with its arguments. The database is also
configured to print `Welcome' when the database is opened. The
database is then closed and reopened.
(require 'database-utilities)
(define my-rdb (create-database "foo.db" 'alist-table))
(define-tables my-rdb
'(*commands*
((name symbol))
((parameters parameter-list)
(procedure expression)
(documentation string))
((define-tables
no-parameters
no-parameter-names
(lambda (rdb) (lambda specs (apply define-tables rdb specs)))
"Create or Augment tables from list of specs")
(*initialize*
no-parameters
no-parameter-names
(lambda (rdb) (display "Welcome") (newline) rdb)
"Print Welcome"))))
((my-rdb 'define-tables)
'(processor-family
((family atom))
((also-ran processor-family))
((m68000 #f)
(m68030 m68000)
(i386 8086)
(8086 #f)
(powerpc #f)))
'(platform
((name symbol))
((processor processor-family)
(os symbol)
(compiler symbol))
((aix powerpc aix -)
(amiga-dice-c m68000 amiga dice-c)
(amiga-aztec m68000 amiga aztec)
(amiga-sas/c-5.10 m68000 amiga sas/c)
(atari-st-gcc m68000 atari gcc)
(atari-st-turbo-c m68000 atari turbo-c)
(borland-c-3.1 8086 ms-dos borland-c)
(djgpp i386 ms-dos gcc)
(linux i386 linux gcc)
(microsoft-c 8086 ms-dos microsoft-c)
(os/2-emx i386 os/2 gcc)
(turbo-c-2 8086 ms-dos turbo-c)
(watcom-9.0 i386 ms-dos watcom))))
((my-rdb 'close-database))
(set! my-rdb (open-database "foo.db" 'alist-table))
-|
Welcome
Balanced binary trees are a useful data structure for maintaining large sets of ordered objects or sets of associations whose keys are ordered. MIT Scheme has an comprehensive implementation of weight-balanced binary trees which has several advantages over the other data structures for large aggregates:
(+ 1 x)
modifies neither the constant 1 nor the value bound to x. The
trees are referentially transparent thus the programmer need not worry
about copying the trees. Referential transparency allows space
efficiency to be achieved by sharing subtrees.
These features make weight-balanced trees suitable for a wide range of applications, especially those that require large numbers of sets or discrete maps. Applications that have a few global databases and/or concentrate on element-level operations like insertion and lookup are probably better off using hash-tables or red-black trees.
The size of a tree is the number of associations that it contains. Weight balanced binary trees are balanced to keep the sizes of the subtrees of each node within a constant factor of each other. This ensures logarithmic times for single-path operations (like lookup and insertion). A weight balanced tree takes space that is proportional to the number of associations in the tree. For the current implementation, the constant of proportionality is six words per association.
Weight balanced trees can be used as an implementation for either
discrete sets or discrete maps (associations). Sets are implemented by
ignoring the datum that is associated with the key. Under this scheme
if an associations exists in the tree this indicates that the key of the
association is a member of the set. Typically a value such as
(), #t or #f is associated with the key.
Many operations can be viewed as computing a result that, depending on
whether the tree arguments are to
thhe arities of each parameter. Corresponds to the
arity field of the command's parameter-table. For a
description of arity see table above.
type-id field of the contents of the domain of the
command's parameter-table.
defaulters field of the command's parameter-table.
nary arity
parameters.
(alias parameter-name). There can be
more than one alias per parameter-name.
For information about parameters, See section Parameter lists. Here is an
example of setting up a command with arguments and parsing those
arguments from a getopt style argument list (see section Getopt).
(require 'database-utilities)
(require 'fluid-let)
(require 'parameters)
(require 'getopt)
(define my-rdb (create-database #f 'alist-table))
(define-tables my-rdb
'(foo-params
*parameter-columns*
*parameter-columns*
((1 single-string single string
(lambda (pl) '("str")) #f "single string")
(2 nary-symbols nary symbol
(lambda (pl) '()) #f "zero or more symbols")
(3 nary1-symbols nary1 symbol
(lambda (pl) '(symb)) #f "one or more symbols")
(4 optional-number optional uint
(lambda (pl) '()) #f "zero or one number")
(5 flag boolean boolean
(lambda (pl) '(#f)) #f "a boolean flag")))
'(foo-pnames
((name string))
((parameter-index uint))
(("s" 1)
("single-string" 1)
("n" 2)
("nary-symbols" 2)
("N" 3)
("nary1-symbols" 3)
("o" 4)
("optional-number" 4)
("f" 5)
("flag" 5)))
'(my-commands
((name symbol))
((parameters parameter-list)
(parameter-names parameter-name-translation)
(procedure expression)
(documentation string))
((foo
foo-params
foo-pnames
(lambda (rdb) (lambda args (print args)))
"test command arguments"))))
(define (dbutil:serve-command-line rdb command-table
command argc argv)
(set! argv (if (vector? argv) (vector->list argv) argv))
((make-command-server rdb command-table)
command
(lambda (comname comval options positions
arities types defaulters dirs aliases)
(apply comval (getopt->arglist
argc argv options positions
arities types defaulters dirs aliases)))))
(define (cmd . opts)
(fluid-let ((*optind* 1))
(printf "%-34s => "
(call-with-output-string (lambda (pt) (write (cons 'cmd opts) pt)))
;;(apply string-append (map (lambda (x) (string-append x " ")) opts))
)
(set! opts (cons "cmd" opts))
(force-output)
(dbutil:serve-command-line
my-rdb 'my-commands 'foo (length opts) opts)))
(cmd) => ("str" () (symb) () #f)
(cmd "-f") => ("str" () (symb) () #t)
(cmd "--flag") => ("str" () (symb) () #t)
(cmd "-o177") => ("str" () (symb) (177) #f)
(cmd "-o" "177") => ("str" () (symb) (177) #f)
(cmd "--optional" "621") => ("str" () (symb) (621) #f)
(cmd "--optional=621") => ("str" () (symb) (621) #f)
(cmd "-s" "speciality") => ("speciality" () (symb) () #f)
(cmd "-sspeciality") => ("speciality" () (symb) () #f)
(cmd "--single" "serendipity") => ("serendipity" () (symb) () #f)
(cmd "--single=serendipity") => ("serendipity" () (symb) () #f)
(cmd "-n" "gravity" "piety") => ("str" () (piety gravity) () #f)
(cmd "-ngravity" "piety") => ("str" () (piety gravity) () #f)
(cmd "--nary" "chastity") => ("str" () (chastity) () #f)
(cmd "--nary=chastity" "") => ("str" () ( chastity) () #f)
(cmd "-N" "calamity") => ("str" () (calamity) () #f)
(cmd "-Ncalamity") => ("str" () (calamity) () #f)
(cmd "--nary1" "surety") => ("str" () (surety) () #f)
(cmd "--nary1=surety") => ("str" () (surety) () #f)
(cmd "-N" "levity" "fealty") => ("str" () (fealty levity) () #f)
(cmd "-Nlevity" "fealty") => ("str" () (fealty levity) () #f)
(cmd "--nary1" "surety" "brevity") => ("str" () (brevity surety) () #f)
(cmd "--nary1=surety" "brevity") => ("str" () (brevity surety) () #f)
(cmd "-?")
-|
Usage: cmd [OPTION ARGUMENT ...] ...
-f, --flag
-o, --optional[=]<number>
-n, --nary[=]<symbols> ...
-N, --nary1[=]<symbols> ...
-s, --single[=]<string>
ERROR: getopt->parameter-list "unrecognized option" "-?"
Some commands are defined in all extended relational-databases. The are called just like section Relational Database Operations.
(car domain-row) and
returns #t. Otherwise returns #f.
For the fields and layout of the domain table, See section Catalog Representation. Currently, these fields are
The following example adds 3 domains to the `build' database.
`Optstring' is either a string or #f. filename is a
string and build-whats is a symbol.
(for-each (build 'add-domain)
'((optstring #f
(lambda (x) (or (not x) (string? x)))
string
#f)
(filename #f #f string #f)
(build-whats #f #f symbol #f)))
(<name> <descriptor-name> <descriptor-name> <rows>)
or
(<name> <primary-key-fields> <other-fields> <rows>)
where <name> is the table name, <descriptor-name> is the symbol name of a descriptor table, <primary-key-fields> and <other-fields> describe the primary keys and other fields respectively, and <rows> is a list of data rows to be added to the table.
<primary-key-fields> and <other-fields> are lists of field descriptors of the form:
(<column-name> <domain>)
or
(<column-name> <domain> <column-integrity-rule>)
where <column-name> is the column name, <domain> is the domain
of the column, and <column-integrity-rule> is an expression whose
value is a procedure of one argument (which returns #f to signal
an error).
If <domain> is not a defined domain name and it matches the name of this table or an already defined (in one of spec-0 ...) single key field table, a foriegn-key domain will be created for it.
*reports* in the relational database rdb.
destination is a port, string, or symbol. If destination is
a:
Each row in the table *reports* has the fields:
format string. At the beginning and end of each page
respectively, format is called with this string and the (list of)
column-names of this table.
format string. For each row in the table, format is
called with this string and the row.
0 if a row's lines should not be broken over page
boundaries.
Each row in the table *printers* has the fields:
The report is prepared as follows:
Format (see section Format (version 3.0)) is called with the header field
and the (list of) column-names of the table.
Format is called with the reporter field and (on
successive calls) each record in the natural order for the table. A
count is kept of the number of newlines output by format. When the
number of newlines to be output exceeds the number of lines per page,
the set of lines will be broken if there are more than
minimum-break left on this page and the number of lines for this
row is larger or equal to twice minimum-break.
Format is called with the footer field and the (list of)
column-names of the table. The footer field should not output a
newline.
The following example shows a new database with the name of `foo.db' being created with tables describing processor families and processor/os/compiler combinations.
The database command define-tables is defined to call
define-tables with its arguments. The database is also
configured to print `Welcome' when the database is opened. The
database is then closed and reopened.
(require 'database-utilities)
(define my-rdb (create-database "foo.db" 'alist-table))
(define-tables my-rdb
'(*commands*
((name symbol))
((parameters parameter-list)
(procedure expression)
(documentation string))
((define-tables
no-parameters
no-parameter-names
(lambda (rdb) (lambda specs (apply define-tables rdb specs)))
"Create or Augment tables from list of specs")
(*initialize*
no-parameters
no-parameter-names
(lambda (rdb) (display "Welcome") (newline) rdb)
"Print Welcome"))))
((my-rdb 'define-tables)
'(processor-family
((family atom))
((also-ran processor-family))
((m68000 #f)
(m68030 m68000)
(i386 8086)
(8086 #f)
(powerpc #f)))
'(platform
((name symbol))
((processor processor-family)
(os symbol)
(compiler symbol))
((aix powerpc aix -)
(amiga-dice-c m68000 amiga dice-c)
(amiga-aztec m68000 amiga aztec)
(amiga-sas/c-5.10 m68000 amiga sas/c)
(atari-st-gcc m68000 atari gcc)
(atari-st-turbo-c m68000 atari turbo-c)
(borland-c-3.1 8086 ms-dos borland-c)
(djgpp i386 ms-dos gcc)
(linux i386 linux gcc)
(microsoft-c 8086 ms-dos microsoft-c)
(os/2-emx i386 os/2 gcc)
(turbo-c-2 8086 ms-dos turbo-c)
(watcom-9.0 i386 ms-dos watcom))))
((my-rdb 'close-database))
(set! my-rdb (open-database "foo.db" 'alist-table))
-|
Welcome
Balanced binary trees are a useful data structure for maintaining large sets of ordered objects or sets of associations whose keys are ordered. MIT Scheme has an comprehensive implementation of weight-balanced binary trees which has several advantages over the other data structures for large aggregates:
(+ 1 x)
modifies neither the constant 1 nor the value bound to x. The
trees are referentially transparent thus the programmer need not worry
about copying the trees. Referential transparency allows space
efficiency to be achieved by sharing subtrees.
These features make weight-balanced trees suitable for a wide range of applications, especially those that require large numbers of sets or discrete maps. Applications that have a few global databases and/or concentrate on element-level operations like insertion and lookup are probably better off using hash-tables or red-black trees.
The size of a tree is the number of associations that it contains. Weight balanced binary trees are balanced to keep the sizes of the subtrees of each node within a constant factor of each other. This ensures logarithmic times for single-path operations (like lookup and insertion). A weight balanced tree takes space that is proportional to the number of associations in the tree. For the current implementation, the constant of proportionality is six words per association.
Weight balanced trees can be used as an implementation for either
discrete sets or discrete maps (associations). Sets are implemented by
ignoring the datum that is associated with the key. Under this scheme
if an associations exists in the tree this indicates that the key of the
association is a member of the set. Typically a value such as
(), #t or #f is associated with the key.
Many operations can be viewed as computing a result that, depending on
whether the tree arguments are to
thhe arities of each parameter. Corresponds to the
arity field of the command's parameter-table. For a
description of arity see table above.
type-id field of the contents of the domain of the
command's parameter-table.
defaulters field of the command's parameter-table.
nary arity
parameters.
(alias parameter-name). There can be
more than one alias per parameter-name.
For information about parameters, See section Parameter lists. Here is an
example of setting up a command with arguments and parsing those
arguments from a getopt style argument list (see section Getopt).
(require 'database-utilities)
(require 'fluid-let)
(require 'parameters)
(require 'getopt)
(define my-rdb (create-database #f 'alist-table))
(define-tables my-rdb
'(foo-params
*parameter-columns*
*parameter-columns*
((1 single-string single string
(lambda (pl) '("str")) #f "single string")
(2 nary-symbols nary symbol
(lambda (pl) '()) #f "zero or more symbols")
(3 nary1-symbols nary1 symbol
(lambda (pl) '(symb)) #f "one or more symbols")
(4 optional-number optional uint
(lambda (pl) '()) #f "zero or one number")
(5 flag boolean boolean
(lambda (pl) '(#f)) #f "a boolean flag")))
'(foo-pnames
((name string))
((parameter-index uint))
(("s" 1)
("single-string" 1)
("n" 2)
("nary-symbols" 2)
("N" 3)
("nary1-symbols" 3)
("o" 4)
("optional-number" 4)
("f" 5)
("flag" 5)))
'(my-commands
((name symbol))
((parameters parameter-list)
(parameter-names parameter-name-translation)
(procedure expression)
(documentation string))
((foo
foo-params
foo-pnames
(lambda (rdb) (lambda args (print args)))
"test command arguments"))))
(define (dbutil:serve-command-line rdb command-table
command argc argv)
(set! argv (if (vector? argv) (vector->list argv) argv))
((make-command-server rdb command-table)
command
(lambda (comname comval options positions
arities types defaulters dirs aliases)
(apply comval (getopt->arglist
argc argv options positions
arities types defaulters dirs aliases)))))
(define (cmd . opts)
(fluid-let ((*optind* 1))
(printf "%-34s => "
(call-with-output-string (lambda (pt) (write (cons 'cmd opts) pt)))
;;(apply string-append (map (lambda (x) (string-append x " ")) opts))
)
(set! opts (cons "cmd" opts))
(force-output)
(dbutil:serve-command-line
my-rdb 'my-commands 'foo (length opts) opts)))
(cmd) => ("str" () (symb) () #f)
(cmd "-f") => ("str" () (symb) () #t)
(cmd "--flag") => ("str" () (symb) () #t)
(cmd "-o177") => ("str" () (symb) (177) #f)
(cmd "-o" "177") => ("str" () (symb) (177) #f)
(cmd "--optional" "621") => ("str" () (symb) (621) #f)
(cmd "--optional=621") => ("str" () (symb) (621) #f)
(cmd "-s" "speciality") => ("speciality" () (symb) () #f)
(cmd "-sspeciality") => ("speciality" () (symb) () #f)
(cmd "--single" "serendipity") => ("serendipity" () (symb) () #f)
(cmd "--single=serendipity") => ("serendipity" () (symb) () #f)
(cmd "-n" "gravity" "piety") => ("str" () (piety gravity) () #f)
(cmd "-ngravity" "piety") => ("str" () (piety gravity) () #f)
(cmd "--nary" "chastity") => ("str" () (chastity) () #f)
(cmd "--nary=chastity" "") => ("str" () ( chastity) () #f)
(cmd "-N" "calamity") => ("str" () (calamity) () #f)
(cmd "-Ncalamity") => ("str" () (calamity) () #f)
(cmd "--nary1" "surety") => ("str" () (surety) () #f)
(cmd "--nary1=surety") => ("str" () (surety) () #f)
(cmd "-N" "levity" "fealty") => ("str" () (fealty levity) () #f)
(cmd "-Nlevity" "fealty") => ("str" () (fealty levity) () #f)
(cmd "--nary1" "surety" "brevity") => ("str" () (brevity surety) () #f)
(cmd "--nary1=surety" "brevity") => ("str" () (brevity surety) () #f)
(cmd "-?")
-|
Usage: cmd [OPTION ARGUMENT ...] ...
-f, --flag
-o, --optional[=]<number>
-n, --nary[=]<symbols> ...
-N, --nary1[=]<symbols> ...
-s, --single[=]<string>
ERROR: getopt->parameter-list "unrecognized option" "-?"
Some commands are defined in all extended relational-databases. The are called just like section Relational Database Operations.
(car domain-row) and
returns #t. Otherwise returns #f.
For the fields and layout of the domain table, See section Catalog Representation. Currently, these fields are
The following example adds 3 domains to the `build' database.
`Optstring' is either a string or #f. filename is a
string and build-whats is a symbol.
(for-each (build 'add-domain)
'((optstring #f
(lambda (x) (or (not x) (string? x)))
string
#f)
(filename #f #f string #f)
(build-whats #f #f symbol #f)))
(<name> <descriptor-name> <descriptor-name> <rows>)
or
(<name> <primary-key-fields> <other-fields> <rows>)
where <name> is the table name, <descriptor-name> is the symbol name of a descriptor table, <primary-key-fields> and <other-fields> describe the primary keys and other fields respectively, and <rows> is a list of data rows to be added to the table.
<primary-key-fields> and <other-fields> are lists of field descriptors of the form:
(<column-name> <domain>)
or
(<column-name> <domain> <column-integrity-rule>)
where <column-name> is the column name, <domain> is the domain
of the column, and <column-integrity-rule> is an expression whose
value is a procedure of one argument (which returns #f to signal
an error).
If <domain> is not a defined domain name and it matches the name of this table or an already defined (in one of spec-0 ...) single key field table, a foriegn-key domain will be created for it.
*reports* in the relational database rdb.
destination is a port, string, or symbol. If destination is
a:
Each row in the table *reports* has the fields:
format string. At the beginning and end of each page
respectively, format is called with this string and the (list of)
column-names of this table.
format string. For each row in the table, format is
called with this string and the row.
0 if a row's lines should not be broken over page
boundaries.
Each row in the table *printers* has the fields:
The report is prepared as follows:
Format (see section Format (version 3.0)) is called with the header field
and the (list of) column-names of the table.
Format is called with the reporter field and (on
successive calls) each record in the natural order for the table. A
count is kept of the number of newlines output by format. When the
number of newlines to be output exceeds the number of lines per page,
the set of lines will be broken if there are more than
minimum-break left on this page and the number of lines for this
row is larger or equal to twice minimum-break.
Format is called with the footer field and the (list of)
column-names of the table. The footer field should not output a
newline.
The following example shows a new database with the name of `foo.db' being created with tables describing processor families and processor/os/compiler combinations.
The database command define-tables is defined to call
define-tables with its arguments. The database is also
configured to print `Welcome' when the database is opened. The
database is then closed and reopened.
(require 'database-utilities)
(define my-rdb (create-database "foo.db" 'alist-table))
(define-tables my-rdb
'(*commands*
((name symbol))
((parameters parameter-list)
(procedure expression)
(documentation string))
((define-tables
no-parameters
no-parameter-names
(lambda (rdb) (lambda specs (apply define-tables rdb specs)))
"Create or Augment tables from list of specs")
(*initialize*
no-parameters
no-parameter-names
(lambda (rdb) (display "Welcome") (newline) rdb)
"Print Welcome"))))
((my-rdb 'define-tables)
'(processor-family
((family atom))
((also-ran processor-family))
((m68000 #f)
(m68030 m68000)
(i386 8086)
(8086 #f)
(powerpc #f)))
'(platform
((name symbol))
((processor processor-family)
(os symbol)
(compiler symbol))
((aix powerpc aix -)
(amiga-dice-c m68000 amiga dice-c)
(amiga-aztec m68000 amiga aztec)
(amiga-sas/c-5.10 m68000 amiga sas/c)
(atari-st-gcc m68000 atari gcc)
(atari-st-turbo-c m68000 atari turbo-c)
(borland-c-3.1 8086 ms-dos borland-c)
(djgpp i386 ms-dos gcc)
(linux i386 linux gcc)
(microsoft-c 8086 ms-dos microsoft-c)
(os/2-emx i386 os/2 gcc)
(turbo-c-2 8086 ms-dos turbo-c)
(watcom-9.0 i386 ms-dos watcom))))
((my-rdb 'close-database))
(set! my-rdb (open-database "foo.db" 'alist-table))
-|
Welcome
Balanced binary trees are a useful data structure for maintaining large sets of ordered objects or sets of associations whose keys are ordered. MIT Scheme has an comprehensive implementation of weight-balanced binary trees which has several advantages over the other data structures for large aggregates:
(+ 1 x)
modifies neither the constant 1 nor the value bound to x. The
trees are referentially transparent thus the programmer need not worry
about copying the trees. Referential transparency allows space
efficiency to be achieved by sharing subtrees.
These features make weight-balanced trees suitable for a wide range of applications, especially those that require large numbers of sets or discrete maps. Applications that have a few global databases and/or concentrate on element-level operations like insertion and lookup are probably better off using hash-tables or red-black trees.
The size of a tree is the number of associations that it contains. Weight balanced binary trees are balanced to keep the sizes of the subtrees of each node within a constant factor of each other. This ensures logarithmic times for single-path operations (like lookup and insertion). A weight balanced tree takes space that is proportional to the number of associations in the tree. For the current implementation, the constant of proportionality is six words per association.
Weight balanced trees can be used as an implementation for either
discrete sets or discrete maps (associations). Sets are implemented by
ignoring the datum that is associated with the key. Under this scheme
if an associations exists in the tree this indicates that the key of the
association is a member of the set. Typically a value such as
(), #t or #f is associated with the key.
Many operations can be viewed as computing a result that, depending on
whether the tree arguments are to
thhe arities of each parameter. Corresponds to the
arity field of the command's parameter-table. For a
description of arity see table above.
type-id field of the contents of the domain of the
command's parameter-table.
defaulters field of the command's parameter-table.
nary arity
parameters.
(alias parameter-name). There can be
more than one alias per parameter-name.
For information about parameters, See section Parameter lists. Here is an
example of setting up a command with arguments and parsing those
arguments from a getopt style argument list (see section Getopt).
(require 'database-utilities)
(require 'fluid-let)
(require 'parameters)
(require 'getopt)
(define my-rdb (create-database #f 'alist-table))
(define-tables my-rdb
'(foo-params
*parameter-columns*
*parameter-columns*
((1 single-string single string
(lambda (pl) '("str")) #f "single string")
(2 nary-symbols nary symbol
(lambda (pl) '()) #f "zero or more symbols")
(3 nary1-symbols nary1 symbol
(lambda (pl) '(symb)) #f "one or more symbols")
(4 optional-number optional uint
(lambda (pl) '()) #f "zero or one number")
(5 flag boolean boolean
(lambda (pl) '(#f)) #f "a boolean flag")))
'(foo-pnames
((name string))
((parameter-index uint))
(("s" 1)
("single-string" 1)
("n" 2)
("nary-symbols" 2)
("N" 3)
("nary1-symbols" 3)
("o" 4)
("optional-number" 4)
("f" 5)
("flag" 5)))
'(my-commands
((name symbol))
((parameters parameter-list)
(parameter-names parameter-name-translation)
(procedure expression)
(documentation string))
((foo
foo-params
foo-pnames
(lambda (rdb) (lambda args (print args)))
"test command arguments"))))
(define (dbutil:serve-command-line rdb command-table
command argc argv)
(set! argv (if (vector? argv) (vector->list argv) argv))
((make-command-server rdb command-table)
command
(lambda (comname comval options positions
arities types defaulters dirs aliases)
(apply comval (getopt->arglist
argc argv options positions
arities types defaulters dirs aliases)))))
(define (cmd . opts)
(fluid-let ((*optind* 1))
(printf "%-34s => "
(call-with-output-string (lambda (pt) (write (cons 'cmd opts) pt)))
;;(apply string-append (map (lambda (x) (string-append x " ")) opts))
)
(set! opts (cons "cmd" opts))
(force-output)
(dbutil:serve-command-line
my-rdb 'my-commands 'foo (length opts) opts)))
(cmd) => ("str" () (symb) () #f)
(cmd "-f") => ("str" () (symb) () #t)
(cmd "--flag") => ("str" () (symb) () #t)
(cmd "-o177") => ("str" () (symb) (177) #f)
(cmd "-o" "177") => ("str" () (symb) (177) #f)
(cmd "--optional" "621") => ("str" () (symb) (621) #f)
(cmd "--optional=621") => ("str" () (symb) (621) #f)
(cmd "-s" "speciality") => ("speciality" () (symb) () #f)
(cmd "-sspeciality") => ("speciality" () (symb) () #f)
(cmd "--single" "serendipity") => ("serendipity" () (symb) () #f)
(cmd "--single=serendipity") => ("serendipity" () (symb) () #f)
(cmd "-n" "gravity" "piety") => ("str" () (piety gravity) () #f)
(cmd "-ngravity" "piety") => ("str" () (piety gravity) () #f)
(cmd "--nary" "chastity") => ("str" () (chastity) () #f)
(cmd "--nary=chastity" "") => ("str" () ( chastity) () #f)
(cmd "-N" "calamity") => ("str" () (calamity) () #f)
(cmd "-Ncalamity") => ("str" () (calamity) () #f)
(cmd "--nary1" "surety") => ("str" () (surety) () #f)
(cmd "--nary1=surety") => ("str" () (surety) () #f)
(cmd "-N" "levity" "fealty") => ("str" () (fealty levity) () #f)
(cmd "-Nlevity" "fealty") => ("str" () (fealty levity) () #f)
(cmd "--nary1" "surety" "brevity") => ("str" () (brevity surety) () #f)
(cmd "--nary1=surety" "brevity") => ("str" () (brevity surety) () #f)
(cmd "-?")
-|
Usage: cmd [OPTION ARGUMENT ...] ...
-f, --flag
-o, --optional[=]<number>
-n, --nary[=]<symbols> ...
-N, --nary1[=]<symbols> ...
-s, --single[=]<string>
ERROR: getopt->parameter-list "unrecognized option" "-?"
Some commands are defined in all extended relational-databases. The are called just like section Relational Database Operations.
(car domain-row) and
returns #t. Otherwise returns #f.
For the fields and layout of the domain table, See section Catalog Representation. Currently, these fields are
The following example adds 3 domains to the `build' database.
`Optstring' is either a string or #f. filename is a
string and build-whats is a symbol.
(for-each (build 'add-domain)
'((optstring #f
(lambda (x) (or (not x) (string? x)))
string
#f)
(filename #f #f string #f)
(build-whats #f #f symbol #f)))
(<name> <descriptor-name> <descriptor-name> <rows>)
or
(<name> <primary-key-fields> <other-fields> <rows>)
where <name> is the table name, <descriptor-name> is the symbol name of a descriptor table, <primary-key-fields> and <other-fields> describe the primary keys and other fields respectively, and <rows> is a list of data rows to be added to the table.
<primary-key-fields> and <other-fields> are lists of field descriptors of the form:
(<column-name> <domain>)
or
(<column-name> <domain> <column-integrity-rule>)
where <column-name> is the column name, <domain> is the domain
of the column, and <column-integrity-rule> is an expression whose
value is a procedure of one argument (which returns #f to signal
an error).
If <domain> is not a defined domain name and it matches the name of this table or an already defined (in one of spec-0 ...) single key field table, a foriegn-key domain will be created for it.
*reports* in the relational database rdb.
destination is a port, string, or symbol. If destination is
a:
Each row in the table *reports* has the fields:
format string. At the beginning and end of each page
respectively, format is called with this string and the (list of)
column-names of this table.
format string. For each row in the table, format is
called with this string and the row.
0 if a row's lines should not be broken over page
boundaries.
Each row in the table *printers* has the fields:
The report is prepared as follows:
Format (see section Format (version 3.0)) is called with the header field
and the (list of) column-names of the table.
Format is called with the reporter field and (on
successive calls) each record in the natural order for the table. A
count is kept of the number of newlines output by format. When the
number of newlines to be output exceeds the number of lines per page,
the set of lines will be broken if there are more than
minimum-break left on this page and the number of lines for this
row is larger or equal to twice minimum-break.
Format is called with the footer field and the (list of)
column-names of the table. The footer field should not output a
newline.
The following example shows a new database with the name of `foo.db' being created with tables describing processor families and processor/os/compiler combinations.
The database command define-tables is defined to call
define-tables with its arguments. The database is also
configured to print `Welcome' when the database is opened. The
database is then closed and reopened.
(require 'database-utilities)
(define my-rdb (create-database "foo.db" 'alist-table))
(define-tables my-rdb
'(*commands*
((name symbol))
((parameters parameter-list)
(procedure expression)
(documentation string))
((define-tables
no-parameters
no-parameter-names
(lambda (rdb) (lambda specs (apply define-tables rdb specs)))
"Create or Augment tables from list of specs")
(*initialize*
no-parameters
no-parameter-names
(lambda (rdb) (display "Welcome") (newline) rdb)
"Print Welcome"))))
((my-rdb 'define-tables)
'(processor-family
((family atom))
((also-ran processor-family))
((m68000 #f)
(m68030 m68000)
(i386 8086)
(8086 #f)
(powerpc #f)))
'(platform
((name symbol))
((processor processor-family)
(os symbol)
(compiler symbol))
((aix powerpc aix -)
(amiga-dice-c m68000 amiga dice-c)
(amiga-aztec m68000 amiga aztec)
(amiga-sas/c-5.10 m68000 amiga sas/c)
(atari-st-gcc m68000 atari gcc)
(atari-st-turbo-c m68000 atari turbo-c)
(borland-c-3.1 8086 ms-dos borland-c)
(djgpp i386 ms-dos gcc)
(linux i386 linux gcc)
(microsoft-c 8086 ms-dos microsoft-c)
(os/2-emx i386 os/2 gcc)
(turbo-c-2 8086 ms-dos turbo-c)
(watcom-9.0 i386 ms-dos watcom))))
((my-rdb 'close-database))
(set! my-rdb (open-database "foo.db" 'alist-table))
-|
Welcome
Balanced binary trees are a useful data structure for maintaining large sets of ordered objects or sets of associations whose keys are ordered. MIT Scheme has an comprehensive implementation of weight-balanced binary trees which has several advantages over the other data structures for large aggregates:
(+ 1 x)
modifies neither the constant 1 nor the value bound to x. The
trees are referentially transparent thus the programmer need not worry
about copying the trees. Referential transparency allows space
efficiency to be achieved by sharing subtrees.
These features make weight-balanced trees suitable for a wide range of applications, especially those that require large numbers of sets or discrete maps. Applications that have a few global databases and/or concentrate on element-level operations like insertion and lookup are probably better off using hash-tables or red-black trees.
The size of a tree is the number of associations that it contains. Weight balanced binary trees are balanced to keep the sizes of the subtrees of each node within a constant factor of each other. This ensures logarithmic times for single-path operations (like lookup and insertion). A weight balanced tree takes space that is proportional to the number of associations in the tree. For the current implementation, the constant of proportionality is six words per association.
Weight balanced trees can be used as an implementation for either
discrete sets or discrete maps (associations). Sets are implemented by
ignoring the datum that is associated with the key. Under this scheme
if an associations exists in the tree this indicates that the key of the
association is a member of the set. Typically a value such as
(), #t or #f is associated with the key.
Many operations can be viewed as computing a result that, depending on
whether the tree arguments are to
thhe arities of each parameter. Corresponds to the
arity field of the command's parameter-table. For a
description of arity see table above.
type-id field of the contents of the domain of the
command's parameter-table.
defaulters field of the command's parameter-table.
nary arity
parameters.
(alias parameter-name). There can be
more than one alias per parameter-name.
For information about parameters, See section Parameter lists. Here is an
example of setting up a command with arguments and parsing those
arguments from a getopt style argument list (see section Getopt).
(require 'database-utilities)
(require 'fluid-let)
(require 'parameters)
(require 'getopt)
(define my-rdb (create-database #f 'alist-table))
(define-tables my-rdb
'(foo-params
*parameter-columns*
*parameter-columns*
((1 single-string single string
(lambda (pl) '("str")) #f "single string")
(2 nary-symbols nary symbol
(lambda (pl) '()) #f "zero or more symbols")
(3 nary1-symbols nary1 symbol
(lambda (pl) '(symb)) #f "one or more symbols")
(4 optional-number optional uint
(lambda (pl) '()) #f "zero or one number")
(5 flag boolean boolean
(lambda (pl) '(#f)) #f "a boolean flag")))
'(foo-pnames
((name string))
((parameter-index uint))
(("s" 1)
("single-string" 1)
("n" 2)
("nary-symbols" 2)
("N" 3)
("nary1-symbols" 3)
("o" 4)
("optional-number" 4)
("f" 5)
("flag" 5)))
'(my-commands
((name symbol))
((parameters parameter-list)
(parameter-names parameter-name-translation)
(procedure expression)
(documentation string))
((foo
foo-params
foo-pnames
(lambda (rdb) (lambda args (print args)))
"test command arguments"))))
(define (dbutil:serve-command-line rdb command-table
command argc argv)
(set! argv (if (vector? argv) (vector->list argv) argv))
((make-command-server rdb command-table)
command
(lambda (comname comval options positions
arities types defaulters dirs aliases)
(apply comval (getopt->arglist
argc argv options positions
arities types defaulters dirs aliases)))))
(define (cmd . opts)
(fluid-let ((*optind* 1))
(printf "%-34s => "
(call-with-output-string (lambda (pt) (write (cons 'cmd opts) pt)))
;;(apply string-append (map (lambda (x) (string-append x " ")) opts))
)
(set! opts (cons "cmd" opts))
(force-output)
(dbutil:serve-command-line
my-rdb 'my-commands 'foo (length opts) opts)))
(cmd) => ("str" () (symb) () #f)
(cmd "-f") => ("str" () (symb) () #t)
(cmd "--flag") => ("str" () (symb) () #t)
(cmd "-o177") => ("str" () (symb) (177) #f)
(cmd "-o" "177") => ("str" () (symb) (177) #f)
(cmd "--optional" "621") => ("str" () (symb) (621) #f)
(cmd "--optional=621") => ("str" () (symb) (621) #f)
(cmd "-s" "speciality") => ("speciality" () (symb) () #f)
(cmd "-sspeciality") => ("speciality" () (symb) () #f)
(cmd "--single" "serendipity") => ("serendipity" () (symb) () #f)
(cmd "--single=serendipity") => ("serendipity" () (symb) () #f)
(cmd "-n" "gravity" "piety") => ("str" () (piety gravity) () #f)
(cmd "-ngravity" "piety") => ("str" () (piety gravity) () #f)
(cmd "--nary" "chastity") => ("str" () (chastity) () #f)
(cmd "--nary=chastity" "") => ("str" () ( chastity) () #f)
(cmd "-N" "calamity") => ("str" () (calamity) () #f)
(cmd "-Ncalamity") => ("str" () (calamity) () #f)
(cmd "--nary1" "surety") => ("str" () (surety) () #f)
(cmd "--nary1=surety") => ("str" () (surety) () #f)
(cmd "-N" "levity" "fealty") => ("str" () (fealty levity) () #f)
(cmd "-Nlevity" "fealty") => ("str" () (fealty levity) () #f)
(cmd "--nary1" "surety" "brevity") => ("str" () (brevity surety) () #f)
(cmd "--nary1=surety" "brevity") => ("str" () (brevity surety) () #f)
(cmd "-?")
-|
Usage: cmd [OPTION ARGUMENT ...] ...
-f, --flag
-o, --optional[=]<number>
-n, --nary[=]<symbols> ...
-N, --nary1[=]<symbols> ...
-s, --single[=]<string>
ERROR: getopt->parameter-list "unrecognized option" "-?"
Some commands are defined in all extended relational-databases. The are called just like section Relational Database Operations.
(car domain-row) and
returns #t. Otherwise returns #f.
For the fields and layout of the domain table, See section Catalog Representation. Currently, these fields are
The following example adds 3 domains to the `build' database.
`Optstring' is either a string or #f. filename is a
string and build-whats is a symbol.
(for-each (build 'add-domain)
'((optstring #f
(lambda (x) (or (not x) (string? x)))
string
#f)
(filename #f #f string #f)
(build-whats #f #f symbol #f)))
(<name> <descriptor-name> <descriptor-name> <rows>)
or
(<name> <primary-key-fields> <other-fields> <rows>)
where <name> is the table name, <descriptor-name> is the symbol name of a descriptor table, <primary-key-fields> and <other-fields> describe the primary keys and other fields respectively, and <rows> is a list of data rows to be added to the table.
<primary-key-fields> and <other-fields> are lists of field descriptors of the form:
(<column-name> <domain>)
or
(<column-name> <domain> <column-integrity-rule>)
where <column-name> is the column name, <domain> is the domain
of the column, and <column-integrity-rule> is an expression whose
value is a procedure of one argument (which returns #f to signal
an error).
If <domain> is not a defined domain name and it matches the name of this table or an already defined (in one of spec-0 ...) single key field table, a foriegn-key domain will be created for it.
*reports* in the relational database rdb.
destination is a port, string, or symbol. If destination is
a:
Each row in the table *reports* has the fields:
format string. At the beginning and end of each page
respectively, format is called with this string and the (list of)
column-names of this table.
format string. For each row in the table, format is
called with this string and the row.
0 if a row's lines should not be broken over page
boundaries.
Each row in the table *printers* has the fields:
The report is prepared as follows:
Format (see section Format (version 3.0)) is called with the header field
and the (list of) column-names of the table.
Format is called with the reporter field and (on
successive calls) each record in the natural order for the table. A
count is kept of the number of newlines output by format. When the
number of newlines to be output exceeds the number of lines per page,
the set of lines will be broken if there are more than
minimum-break left on this page and the number of lines for this
row is larger or equal to twice minimum-break.
Format is called with the footer field and the (list of)
column-names of the table. The footer field should not output a
newline.
The following example shows a new database with the name of `foo.db' being created with tables describing processor families and processor/os/compiler combinations.
The database command define-tables is defined to call
define-tables with its arguments. The database is also
configured to print `Welcome' when the database is opened. The
database is then closed and reopened.
(require 'database-utilities)
(define my-rdb (create-database "foo.db" 'alist-table))
(define-tables my-rdb
'(*commands*
((name symbol))
((parameters parameter-list)
(procedure expression)
(documentation string))
((define-tables
no-parameters
no-parameter-names
(lambda (rdb) (lambda specs (apply define-tables rdb specs)))
"Create or Augment tables from list of specs")
(*initialize*
no-parameters
no-parameter-names
(lambda (rdb) (display "Welcome") (newline) rdb)
"Print Welcome"))))
((my-rdb 'define-tables)
'(processor-family
((family atom))
((also-ran processor-family))
((m68000 #f)
(m68030 m68000)
(i386 8086)
(8086 #f)
(powerpc #f)))
'(platform
((name symbol))
((processor processor-family)
(os symbol)
(compiler symbol))
((aix powerpc aix -)
(amiga-dice-c m68000 amiga dice-c)
(amiga-aztec m68000 amiga aztec)
(amiga-sas/c-5.10 m68000 amiga sas/c)
(atari-st-gcc m68000 atari gcc)
(atari-st-turbo-c m68000 atari turbo-c)
(borland-c-3.1 8086 ms-dos borland-c)
(djgpp i386 ms-dos gcc)
(linux i386 linux gcc)
(microsoft-c 8086 ms-dos microsoft-c)
(os/2-emx i386 os/2 gcc)
(turbo-c-2 8086 ms-dos turbo-c)
(watcom-9.0 i386 ms-dos watcom))))
((my-rdb 'close-database))
(set! my-rdb (open-database "foo.db" 'alist-table))
-|
Welcome
Balanced binary trees are a useful data structure for maintaining large sets of ordered objects or sets of associations whose keys are ordered. MIT Scheme has an comprehensive implementation of weight-balanced binary trees which has several advantages over the other data structures for large aggregates:
(+ 1 x)
modifies neither the constant 1 nor the value bound to x. The
trees are referentially transparent thus the programmer need not worry
about copying the trees. Referential transparency allows space
efficiency to be achieved by sharing subtrees.
These features make weight-balanced trees suitable for a wide range of applications, especially those that require large numbers of sets or discrete maps. Applications that have a few global databases and/or concentrate on element-level operations like insertion and lookup are probably better off using hash-tables or red-black trees.
The size of a tree is the number of associations that it contains. Weight balanced binary trees are balanced to keep the sizes of the subtrees of each node within a constant factor of each other. This ensures logarithmic times for single-path operations (like lookup and insertion). A weight balanced tree takes space that is proportional to the number of associations in the tree. For the current implementation, the constant of proportionality is six words per association.
Weight balanced trees can be used as an implementation for either
discrete sets or discrete maps (associations). Sets are implemented by
ignoring the datum that is associated with the key. Under this scheme
if an associations exists in the tree this indicates that the key of the
association is a member of the set. Typically a value such as
(), #t or #f is associated with the key.
Many operations can be viewed as computing a result that, depending on
whether the tree arguments are to
thhe arities of each parameter. Corresponds to the
arity field of the command's parameter-table. For a
description of arity see table above.
type-id field of the contents of the domain of the
command's parameter-table.
defaulters field of the command's parameter-table.
nary arity
parameters.
(alias parameter-name). There can be
more than one alias per parameter-name.
For information about parameters, See section Parameter lists. Here is an
example of setting up a command with arguments and parsing those
arguments from a getopt style argument list (see section Getopt).
(require 'database-utilities)
(require 'fluid-let)
(require 'parameters)
(require 'getopt)
(define my-rdb (create-database #f 'alist-table))
(define-tables my-rdb
'(foo-params
*parameter-columns*
*parameter-columns*
((1 single-string single string
(lambda (pl) '("str")) #f "single string")
(2 nary-symbols nary symbol
(lambda (pl) '()) #f "zero or more symbols")
(3 nary1-symbols nary1 symbol
(lambda (pl) '(symb)) #f "one or more symbols")
(4 optional-number optional uint
(lambda (pl) '()) #f "zero or one number")
(5 flag boolean boolean
(lambda (pl) '(#f)) #f "a boolean flag")))
'(foo-pnames
((name string))
((parameter-index uint))
(("s" 1)
("single-string" 1)
("n" 2)
("nary-symbols" 2)
("N" 3)
("nary1-symbols" 3)
("o" 4)
("optional-number" 4)
("f" 5)
("flag" 5)))
'(my-commands
((name symbol))
((parameters parameter-list)
(parameter-names parameter-name-translation)
(procedure expression)
(documentation string))
((foo
foo-params
foo-pnames
(lambda (rdb) (lambda args (print args)))
"test command arguments"))))
(define (dbutil:serve-command-line rdb command-table
command argc argv)
(set! argv (if (vector? argv) (vector->list argv) argv))
((make-command-server rdb command-table)
command
(lambda (comname comval options positions
arities types defaulters dirs aliases)
(apply comval (getopt->arglist
argc argv options positions
arities types defaulters dirs aliases)))))
(define (cmd . opts)
(fluid-let ((*optind* 1))
(printf "%-34s => "
(call-with-output-string (lambda (pt) (write (cons 'cmd opts) pt)))
;;(apply string-append (map (lambda (x) (string-append x " ")) opts))
)
(set! opts (cons "cmd" opts))
(force-output)
(dbutil:serve-command-line
my-rdb 'my-commands 'foo (length opts) opts)))
(cmd) => ("str" () (symb) () #f)
(cmd "-f") => ("str" () (symb) () #t)
(cmd "--flag") => ("str" () (symb) () #t)
(cmd "-o177") => ("str" () (symb) (177) #f)
(cmd "-o" "177") => ("str" () (symb) (177) #f)
(cmd "--optional" "621") => ("str" () (symb) (621) #f)
(cmd "--optional=621") => ("str" () (symb) (621) #f)
(cmd "-s" "speciality") => ("speciality" () (symb) () #f)
(cmd "-sspeciality") => ("speciality" () (symb) () #f)
(cmd "--single" "serendipity") => ("serendipity" () (symb) () #f)
(cmd "--single=serendipity") => ("serendipity" () (symb) () #f)
(cmd "-n" "gravity" "piety") => ("str" () (piety gravity) () #f)
(cmd "-ngravity" "piety") => ("str" () (piety gravity) () #f)
(cmd "--nary" "chastity") => ("str" () (chastity) () #f)
(cmd "--nary=chastity" "") => ("str" () ( chastity) () #f)
(cmd "-N" "calamity") => ("str" () (calamity) () #f)
(cmd "-Ncalamity") => ("str" () (calamity) () #f)
(cmd "--nary1" "surety") => ("str" () (surety) () #f)
(cmd "--nary1=surety") => ("str" () (surety) () #f)
(cmd "-N" "levity" "fealty") => ("str" () (fealty levity) () #f)
(cmd "-Nlevity" "fealty") => ("str" () (fealty levity) () #f)
(cmd "--nary1" "surety" "brevity") => ("str" () (brevity surety) () #f)
(cmd "--nary1=surety" "brevity") => ("str" () (brevity surety) () #f)
(cmd "-?")
-|
Usage: cmd [OPTION ARGUMENT ...] ...
-f, --flag
-o, --optional[=]<number>
-n, --nary[=]<symbols> ...
-N, --nary1[=]<symbols> ...
-s, --single[=]<string>
ERROR: getopt->parameter-list "unrecognized option" "-?"
Some commands are defined in all extended relational-databases. The are called just like section Relational Database Operations.
(car domain-row) and
returns #t. Otherwise returns #f.
For the fields and layout of the domain table, See section Catalog Representation. Currently, these fields are
The following example adds 3 domains to the `build' database.
`Optstring' is either a string or #f. filename is a
string and build-whats is a symbol.
(for-each (build 'add-domain)
'((optstring #f
(lambda (x) (or (not x) (string? x)))
string
#f)
(filename #f #f string #f)
(build-whats #f #f symbol #f)))
(<name> <descriptor-name> <descriptor-name> <rows>)
or
(<name> <primary-key-fields> <other-fields> <rows>)
where <name> is the table name, <descriptor-name> is the symbol name of a descriptor table, <primary-key-fields> and <other-fields> describe the primary keys and other fields respectively, and <rows> is a list of data rows to be added to the table.
<primary-key-fields> and <other-fields> are lists of field descriptors of the form:
(<column-name> <domain>)
or
(<column-name> <domain> <column-integrity-rule>)
where <column-name> is the column name, <domain> is the domain
of the column, and <column-integrity-rule> is an expression whose
value is a procedure of one argument (which returns #f to signal
an error).
If <domain> is not a defined domain name and it matches the name of this table or an already defined (in one of spec-0 ...) single key field table, a foriegn-key domain will be created for it.
*reports* in the relational database rdb.
destination is a port, string, or symbol. If destination is
a:
Each row in the table *reports* has the fields:
format string. At the beginning and end of each page
respectively, format is called with this string and the (list of)
column-names of this table.
format string. For each row in the table, format is
called with this string and the row.
0 if a row's lines should not be broken over page
boundaries.
Each row in the table *printers* has the fields:
The report is prepared as follows:
Format (see section Format (version 3.0)) is called with the header field
and the (list of) column-names of the table.
Format is called with the reporter field and (on
successive calls) each record in the natural order for the table. A
count is kept of the number of newlines output by format. When the
number of newlines to be output exceeds the number of lines per page,
the set of lines will be broken if there are more than
minimum-break left on this page and the number of lines for this
row is larger or equal to twice minimum-break.
Format is called with the footer field and the (list of)
column-names of the table. The footer field should not output a
newline.
The following example shows a new database with the name of `foo.db' being created with tables describing processor families and processor/os/compiler combinations.
The database command define-tables is defined to call
define-tables with its arguments. The database is also
configured to print `Welcome' when the database is opened. The
database is then closed and reopened.
(require 'database-utilities)
(define my-rdb (create-database "foo.db" 'alist-table))
(define-tables my-rdb
'(*commands*
((name symbol))
((parameters parameter-list)
(procedure expression)
(documentation string))
((define-tables
no-parameters
no-parameter-names
(lambda (rdb) (lambda specs (apply define-tables rdb specs)))
"Create or Augment tables from list of specs")
(*initialize*
no-parameters
no-parameter-names
(lambda (rdb) (display "Welcome") (newline) rdb)
"Print Welcome"))))
((my-rdb 'define-tables)
'(processor-family
((family atom))
((also-ran processor-family))
((m68000 #f)
(m68030 m68000)
(i386 8086)
(8086 #f)
(powerpc #f)))
'(platform
((name symbol))
((processor processor-family)
(os symbol)
(compiler symbol))
((aix powerpc aix -)
(amiga-dice-c m68000 amiga dice-c)
(amiga-aztec m68000 amiga aztec)
(amiga-sas/c-5.10 m68000 amiga sas/c)
(atari-st-gcc m68000 atari gcc)
(atari-st-turbo-c m68000 atari turbo-c)
(borland-c-3.1 8086 ms-dos borland-c)
(djgpp i386 ms-dos gcc)
(linux i386 linux gcc)
(microsoft-c 8086 ms-dos microsoft-c)
(os/2-emx i386 os/2 gcc)
(turbo-c-2 8086 ms-dos turbo-c)
(watcom-9.0 i386 ms-dos watcom))))
((my-rdb 'close-database))
(set! my-rdb (open-database "foo.db" 'alist-table))
-|
Welcome
Balanced binary trees are a useful data structure for maintaining large sets of ordered objects or sets of associations whose keys are ordered. MIT Scheme has an comprehensive implementation of weight-balanced binary trees which has several advantages over the other data structures for large aggregates:
(+ 1 x)
modifies neither the constant 1 nor the value bound to x. The
trees are referentially transparent thus the programmer need not worry
about copying the trees. Referential transparency allows space
efficiency to be achieved by sharing subtrees.
These features make weight-balanced trees suitable for a wide range of applications, especially those that require large numbers of sets or discrete maps. Applications that have a few global databases and/or concentrate on element-level operations like insertion and lookup are probably better off using hash-tables or red-black trees.
The size of a tree is the number of associations that it contains. Weight balanced binary trees are balanced to keep the sizes of the subtrees of each node within a constant factor of each other. This ensures logarithmic times for single-path operations (like lookup and insertion). A weight balanced tree takes space that is proportional to the number of associations in the tree. For the current implementation, the constant of proportionality is six words per association.
Weight balanced trees can be used as an implementation for either
discrete sets or discrete maps (associations). Sets are implemented by
ignoring the datum that is associated with the key. Under this scheme
if an associations exists in the tree this indicates that the key of the
association is a member of the set. Typically a value such as
(), #t or #f is associated with the key.
Many operations can be viewed as computing a result that, depending on
whether the tree arguments are to
thhe arities of each parameter. Corresponds to the
arity field of the command's parameter-table. For a
description of arity see table above.
type-id field of the contents of the domain of the
command's parameter-table.
defaulters field of the command's parameter-table.
nary arity
parameters.
(alias parameter-name). There can be
more than one alias per parameter-name.
For information about parameters, See section Parameter lists. Here is an
example of setting up a command with arguments and parsing those
arguments from a getopt style argument list (see section Getopt).
(require 'database-utilities)
(require 'fluid-let)
(require 'parameters)
(require 'getopt)
(define my-rdb (create-database #f 'alist-table))
(define-tables my-rdb
'(foo-params
*parameter-columns*
*parameter-columns*
((1 single-string single string
(lambda (pl) '("str")) #f "single string")
(2 nary-symbols nary symbol
(lambda (pl) '()) #f "zero or more symbols")
(3 nary1-symbols nary1 symbol
(lambda (pl) '(symb)) #f "one or more symbols")
(4 optional-number optional uint
(lambda (pl) '()) #f "zero or one number")
(5 flag boolean boolean
(lambda (pl) '(#f)) #f "a boolean flag")))
'(foo-pnames
((name string))
((parameter-index uint))
(("s" 1)
("single-string" 1)
("n" 2)
("nary-symbols" 2)
("N" 3)
("nary1-symbols" 3)
("o" 4)
("optional-number" 4)
("f" 5)
("flag" 5)))
'(my-commands
((name symbol))
((parameters parameter-list)
(parameter-names parameter-name-translation)
(procedure expression)
(documentation string))
((foo
foo-params
foo-pnames
(lambda (rdb) (lambda args (print args)))
"test command arguments"))))
(define (dbutil:serve-command-line rdb command-table
command argc argv)
(set! argv (if (vector? argv) (vector->list argv) argv))
((make-command-server rdb command-table)
command
(lambda (comname comval options positions
arities types defaulters dirs aliases)
(apply comval (getopt->arglist
argc argv options positions
arities types defaulters dirs aliases)))))
(define (cmd . opts)
(fluid-let ((*optind* 1))
(printf "%-34s => "
(call-with-output-string (lambda (pt) (write (cons 'cmd opts) pt)))
;;(apply string-append (map (lambda (x) (string-append x " ")) opts))
)
(set! opts (cons "cmd" opts))
(force-output)
(dbutil:serve-command-line
my-rdb 'my-commands 'foo (length opts) opts)))
(cmd) => ("str" () (symb) () #f)
(cmd "-f") => ("str" () (symb) () #t)
(cmd "--flag") => ("str" () (symb) () #t)
(cmd "-o177") => ("str" () (symb) (177) #f)
(cmd "-o" "177") => ("str" () (symb) (177) #f)
(cmd "--optional" "621") => ("str" () (symb) (621) #f)
(cmd "--optional=621") => ("str" () (symb) (621) #f)
(cmd "-s" "speciality") => ("speciality" () (symb) () #f)
(cmd "-sspeciality") => ("speciality" () (symb) () #f)
(cmd "--single" "serendipity") => ("serendipity" () (symb) () #f)
(cmd "--single=serendipity") => ("serendipity" () (symb) () #f)
(cmd "-n" "gravity" "piety") => ("str" () (piety gravity) () #f)
(cmd "-ngravity" "piety") => ("str" () (piety gravity) () #f)
(cmd "--nary" "chastity") => ("str" () (chastity) () #f)
(cmd "--nary=chastity" "") => ("str" () ( chastity) () #f)
(cmd "-N" "calamity") => ("str" () (calamity) () #f)
(cmd "-Ncalamity") => ("str" () (calamity) () #f)
(cmd "--nary1" "surety") => ("str" () (surety) () #f)
(cmd "--nary1=surety") => ("str" () (surety) () #f)
(cmd "-N" "levity" "fealty") => ("str" () (fealty levity) () #f)
(cmd "-Nlevity" "fealty") => ("str" () (fealty levity) () #f)
(cmd "--nary1" "surety" "brevity") => ("str" () (brevity surety) () #f)
(cmd "--nary1=surety" "brevity") => ("str" () (brevity surety) () #f)
(cmd "-?")
-|
Usage: cmd [OPTION ARGUMENT ...] ...
-f, --flag
-o, --optional[=]<number>
-n, --nary[=]<symbols> ...
-N, --nary1[=]<symbols> ...
-s, --single[=]<string>
ERROR: getopt->parameter-list "unrecognized option" "-?"
Some commands are defined in all extended relational-databases. The are called just like section Relational Database Operations.
(car domain-row) and
returns #t. Otherwise returns #f.
For the fields and layout of the domain table, See section Catalog Representation. Currently, these fields are
The following example adds 3 domains to the `build' database.
`Optstring' is either a string or #f. filename is a
string and build-whats is a symbol.
(for-each (build 'add-domain)
'((optstring #f
(lambda (x) (or (not x) (string? x)))
string
#f)
(filename #f #f string #f)
(build-whats #f #f symbol #f)))
(<name> <descriptor-name> <descriptor-name> <rows>)
or
(<name> <primary-key-fields> <other-fields> <rows>)
where <name> is the table name, <descriptor-name> is the symbol name of a descriptor table, <primary-key-fields> and <other-fields> describe the primary keys and other fields respectively, and <rows> is a list of data rows to be added to the table.
<primary-key-fields> and <other-fields> are lists of field descriptors of the form:
(<column-name> <domain>)
or
(<column-name> <domain> <column-integrity-rule>)
where <column-name> is the column name, <domain> is the domain
of the column, and <column-integrity-rule> is an expression whose
value is a procedure of one argument (which returns #f to signal
an error).
If <domain> is not a defined domain name and it matches the name of this table or an already defined (in one of spec-0 ...) single key field table, a foriegn-key domain will be created for it.
*reports* in the relational database rdb.
destination is a port, string, or symbol. If destination is
a:
Each row in the table *reports* has the fields:
format string. At the beginning and end of each page
respectively, format is called with this string and the (list of)
column-names of this table.
format string. For each row in the table, format is
called with this string and the row.
0 if a row's lines should not be broken over page
boundaries.
Each row in the table *printers* has the fields:
The report is prepared as follows:
Format (see section Format (version 3.0)) is called with the header field
and the (list of) column-names of the table.
Format is called with the reporter field and (on
successive calls) each record in the natural order for the table. A
count is kept of the number of newlines output by format. When the
number of newlines to be output exceeds the number of lines per page,
the set of lines will be broken if there are more than
minimum-break left on this page and the number of lines for this
row is larger or equal to twice minimum-break.
Format is called with the footer field and the (list of)
column-names of the table. The footer field should not output a
newline.
The following example shows a new database with the name of `foo.db' being created with tables describing processor families and processor/os/compiler combinations.
The database command define-tables is defined to call
define-tables with its arguments. The database is also
configured to print `Welcome' when the database is opened. The
database is then closed and reopened.
(require 'database-utilities)
(define my-rdb (create-database "foo.db" 'alist-table))
(define-tables my-rdb
'(*commands*
((name symbol))
((parameters parameter-list)
(procedure expression)
(documentation string))
((define-tables
no-parameters
no-parameter-names
(lambda (rdb) (lambda specs (apply define-tables rdb specs)))
"Create or Augment tables from list of specs")
(*initialize*
no-parameters
no-parameter-names
(lambda (rdb) (display "Welcome") (newline) rdb)
"Print Welcome"))))
((my-rdb 'define-tables)
'(processor-family
((family atom))
((also-ran processor-family))
((m68000 #f)
(m68030 m68000)
(i386 8086)
(8086 #f)
(powerpc #f)))
'(platform
((name symbol))
((processor processor-family)
(os symbol)
(compiler symbol))
((aix powerpc aix -)
(amiga-dice-c m68000 amiga dice-c)
(amiga-aztec m68000 amiga aztec)
(amiga-sas/c-5.10 m68000 amiga sas/c)
(atari-st-gcc m68000 atari gcc)
(atari-st-turbo-c m68000 atari turbo-c)
(borland-c-3.1 8086 ms-dos borland-c)
(djgpp i386 ms-dos gcc)
(linux i386 linux gcc)
(microsoft-c 8086 ms-dos microsoft-c)
(os/2-emx i386 os/2 gcc)
(turbo-c-2 8086 ms-dos turbo-c)
(watcom-9.0 i386 ms-dos watcom))))
((my-rdb 'close-database))
(set! my-rdb (open-database "foo.db" 'alist-table))
-|
Welcome
Balanced binary trees are a useful data structure for maintaining large sets of ordered objects or sets of associations whose keys are ordered. MIT Scheme has an comprehensive implementation of weight-balanced binary trees which has several advantages over the other data structures for large aggregates:
(+ 1 x)
modifies neither the constant 1 nor the value bound to x. The
trees are referentially transparent thus the programmer need not worry
about copying the trees. Referential transparency allows space
efficiency to be achieved by sharing subtrees.
These features make weight-balanced trees suitable for a wide range of applications, especially those that require large numbers of sets or discrete maps. Applications that have a few global databases and/or concentrate on element-level operations like insertion and lookup are probably better off using hash-tables or red-black trees.
The size of a tree is the number of associations that it contains. Weight balanced binary trees are balanced to keep the sizes of the subtrees of each node within a constant factor of each other. This ensures logarithmic times for single-path operations (like lookup and insertion). A weight balanced tree takes space that is proportional to the number of associations in the tree. For the current implementation, the constant of proportionality is six words per association.
Weight balanced trees can be used as an implementation for either
discrete sets or discrete maps (associations). Sets are implemented by
ignoring the datum that is associated with the key. Under this scheme
if an associations exists in the tree this indicates that the key of the
association is a member of the set. Typically a value such as
(), #t or #f is associated with the key.
Many operations can be viewed as computing a result that, depending on
whether the tree arguments are to
thhe arities of each parameter. Corresponds to the
arity field of the command's parameter-table. For a
description of arity see table above.
type-id field of the contents of the domain of the
command's parameter-table.
defaulters field of the command's parameter-table.
nary arity
parameters.
(alias parameter-name). There can be
more than one alias per parameter-name.
For information about parameters, See section Parameter lists. Here is an
example of setting up a command with arguments and parsing those
arguments from a getopt style argument list (see section Getopt).
(require 'database-utilities)
(require 'fluid-let)
(require 'parameters)
(require 'getopt)
(define my-rdb (create-database #f 'alist-table))
(define-tables my-rdb
'(foo-params
*parameter-columns*
*parameter-columns*
((1 single-string single string
(lambda (pl) '("str")) #f "single string")
(2 nary-symbols nary symbol
(lambda (pl) '()) #f "zero or more symbols")
(3 nary1-symbols nary1 symbol
(lambda (pl) '(symb)) #f "one or more symbols")
(4 optional-number optional uint
(lambda (pl) '()) #f "zero or one number")
(5 flag boolean boolean
(lambda (pl) '(#f)) #f "a boolean flag")))
'(foo-pnames
((name string))
((parameter-index uint))
(("s" 1)
("single-string" 1)
("n" 2)
("nary-symbols" 2)
("N" 3)
("nary1-symbols" 3)
("o" 4)
("optional-number" 4)
("f" 5)
("flag" 5)))
'(my-commands
((name symbol))
((parameters parameter-list)
(parameter-names parameter-name-translation)
(procedure expression)
(documentation string))
((foo
foo-params
foo-pnames
(lambda (rdb) (lambda args (print args)))
"test command arguments"))))
(define (dbutil:serve-command-line rdb command-table
command argc argv)
(set! argv (if (vector? argv) (vector->list argv) argv))
((make-command-server rdb command-table)
command
(lambda (comname comval options positions
arities types defaulters dirs aliases)
(apply comval (getopt->arglist
argc argv options positions
arities types defaulters dirs aliases)))))
(define (cmd . opts)
(fluid-let ((*optind* 1))
(printf "%-34s => "
(call-with-output-string (lambda (pt) (write (cons 'cmd opts) pt)))
;;(apply string-append (map (lambda (x) (string-append x " ")) opts))
)
(set! opts (cons "cmd" opts))
(force-output)
(dbutil:serve-command-line
my-rdb 'my-commands 'foo (length opts) opts)))
(cmd) => ("str" () (symb) () #f)
(cmd "-f") => ("str" () (symb) () #t)
(cmd "--flag") => ("str" () (symb) () #t)
(cmd "-o177") => ("str" () (symb) (177) #f)
(cmd "-o" "177") => ("str" () (symb) (177) #f)
(cmd "--optional" "621") => ("str" () (symb) (621) #f)
(cmd "--optional=621") => ("str" () (symb) (621) #f)
(cmd "-s" "speciality") => ("speciality" () (symb) () #f)
(cmd "-sspeciality") => ("speciality" () (symb) () #f)
(cmd "--single" "serendipity") => ("serendipity" () (symb) () #f)
(cmd "--single=serendipity") => ("serendipity" () (symb) () #f)
(cmd "-n" "gravity" "piety") => ("str" () (piety gravity) () #f)
(cmd "-ngravity" "piety") => ("str" () (piety gravity) () #f)
(cmd "--nary" "chastity") => ("str" () (chastity) () #f)
(cmd "--nary=chastity" "") => ("str" () ( chastity) () #f)
(cmd "-N" "calamity") => ("str" () (calamity) () #f)
(cmd "-Ncalamity") => ("str" () (calamity) () #f)
(cmd "--nary1" "surety") => ("str" () (surety) () #f)
(cmd "--nary1=surety") => ("str" () (surety) () #f)
(cmd "-N" "levity" "fealty") => ("str" () (fealty levity) () #f)
(cmd "-Nlevity" "fealty") => ("str" () (fealty levity) () #f)
(cmd "--nary1" "surety" "brevity") => ("str" () (brevity surety) () #f)
(cmd "--nary1=surety" "brevity") => ("str" () (brevity surety) () #f)
(cmd "-?")
-|
Usage: cmd [OPTION ARGUMENT ...] ...
-f, --flag
-o, --optional[=]<number>
-n, --nary[=]<symbols> ...
-N, --nary1[=]<symbols> ...
-s, --single[=]<string>
ERROR: getopt->parameter-list "unrecognized option" "-?"
Some commands are defined in all extended relational-databases. The are called just like section Relational Database Operations.
(car domain-row) and
returns #t. Otherwise returns #f.
For the fields and layout of the domain table, See section Catalog Representation. Currently, these fields are
The following example adds 3 domains to the `build' database.
`Optstring' is either a string or #f. filename is a
string and build-whats is a symbol.
(for-each (build 'add-domain)
'((optstring #f
(lambda (x) (or (not x) (string? x)))
string
#f)
(filename #f #f string #f)
(build-whats #f #f symbol #f)))
(<name> <descriptor-name> <descriptor-name> <rows>)
or
(<name> <primary-key-fields> <other-fields> <rows>)
where <name> is the table name, <descriptor-name> is the symbol name of a descriptor table, <primary-key-fields> and <other-fields> describe the primary keys and other fields respectively, and <rows> is a list of data rows to be added to the table.
<primary-key-fields> and <other-fields> are lists of field descriptors of the form:
(<column-name> <domain>)
or
(<column-name> <domain> <column-integrity-rule>)
where <column-name> is the column name, <domain> is the domain
of the column, and <column-integrity-rule> is an expression whose
value is a procedure of one argument (which returns #f to signal
an error).
If <domain> is not a defined domain name and it matches the name of this table or an already defined (in one of spec-0 ...) single key field table, a foriegn-key domain will be created for it.
*reports* in the relational database rdb.
destination is a port, string, or symbol. If destination is
a:
Each row in the table *reports* has the fields:
format string. At the beginning and end of each page
respectively, format is called with this string and the (list of)
column-names of this table.
format string. For each row in the table, format is
called with this string and the row.
0 if a row's lines should not be broken over page
boundaries.
Each row in the table *printers* has the fields:
The report is prepared as follows:
Format (see section Format (version 3.0)) is called with the header field
and the (list of) column-names of the table.
Format is called with the reporter field and (on
successive calls) each record in the natural order for the table. A
count is kept of the number of newlines output by format. When the
number of newlines to be output exceeds the number of lines per page,
the set of lines will be broken if there are more than
minimum-break left on this page and the number of lines for this
row is larger or equal to twice minimum-break.
Format is called with the footer field and the (list of)
column-names of the table. The footer field should not output a
newline.
The following example shows a new database with the name of `foo.db' being created with tables describing processor families and processor/os/compiler combinations.
The database command define-tables is defined to call
define-tables with its arguments. The database is also
configured to print `Welcome' when the database is opened. The
database is then closed and reopened.
(require 'database-utilities)
(define my-rdb (create-database "foo.db" 'alist-table))
(define-tables my-rdb
'(*commands*
((name symbol))
((parameters parameter-list)
(procedure expression)
(documentation string))
((define-tables
no-parameters
no-parameter-names
(lambda (rdb) (lambda specs (apply define-tables rdb specs)))
"Create or Augment tables from list of specs")
(*initialize*
no-parameters
no-parameter-names
(lambda (rdb) (display "Welcome") (newline) rdb)
"Print Welcome"))))
((my-rdb 'define-tables)
'(processor-family
((family atom))
((also-ran processor-family))
((m68000 #f)
(m68030 m68000)
(i386 8086)
(8086 #f)
(powerpc #f)))
'(platform
((name symbol))
((processor processor-family)
(os symbol)
(compiler symbol))
((aix powerpc aix -)
(amiga-dice-c m68000 amiga dice-c)
(amiga-aztec m68000 amiga aztec)
(amiga-sas/c-5.10 m68000 amiga sas/c)
(atari-st-gcc m68000 atari gcc)
(atari-st-turbo-c m68000 atari turbo-c)
(borland-c-3.1 8086 ms-dos borland-c)
(djgpp i386 ms-dos gcc)
(linux i386 linux gcc)
(microsoft-c 8086 ms-dos microsoft-c)
(os/2-emx i386 os/2 gcc)
(turbo-c-2 8086 ms-dos turbo-c)
(watcom-9.0 i386 ms-dos watcom))))
((my-rdb 'close-database))
(set! my-rdb (open-database "foo.db" 'alist-table))
-|
Welcome
Balanced binary trees are a useful data structure for maintaining large sets of ordered objects or sets of associations whose keys are ordered. MIT Scheme has an comprehensive implementation of weight-balanced binary trees which has several advantages over the other data structures for large aggregates:
(+ 1 x)
modifies neither the constant 1 nor the value bound to x. The
trees are referentially transparent thus the programmer need not worry
about copying the trees. Referential transparency allows space
efficiency to be achieved by sharing subtrees.
These features make weight-balanced trees suitable for a wide range of applications, especially those that require large numbers of sets or discrete maps. Applications that have a few global databases and/or concentrate on element-level operations like insertion and lookup are probably better off using hash-tables or red-black trees.
The size of a tree is the number of associations that it contains. Weight balanced binary trees are balanced to keep the sizes of the subtrees of each node within a constant factor of each other. This ensures logarithmic times for single-path operations (like lookup and insertion). A weight balanced tree takes space that is proportional to the number of associations in the tree. For the current implementation, the constant of proportionality is six words per association.
Weight balanced trees can be used as an implementation for either
discrete sets or discrete maps (associations). Sets are implemented by
ignoring the datum that is associated with the key. Under this scheme
if an associations exists in the tree this indicates that the key of the
association is a member of the set. Typically a value such as
(), #t or #f is associated with the key.
Many operations can be viewed as computing a result that, depending on
whether the tree arguments are to
thhe arities of each parameter. Corresponds to the
arity field of the command's parameter-table. For a
description of arity see table above.
type-id field of the contents of the domain of the
command's parameter-table.
defaulters field of the command's parameter-table.
nary arity
parameters.
(alias parameter-name). There can be
more than one alias per parameter-name.
For information about parameters, See section Parameter lists. Here is an
example of setting up a command with arguments and parsing those
arguments from a getopt style argument list (see section Getopt).
(require 'database-utilities)
(require 'fluid-let)
(require 'parameters)
(require 'getopt)
(define my-rdb (create-database #f 'alist-table))
(define-tables my-rdb
'(foo-params
*parameter-columns*
*parameter-columns*
((1 single-string single string
(lambda (pl) '("str")) #f "single string")
(2 nary-symbols nary symbol
(lambda (pl) '()) #f "zero or more symbols")
(3 nary1-symbols nary1 symbol
(lambda (pl) '(symb)) #f "one or more symbols")
(4 optional-number optional uint
(lambda (pl) '()) #f "zero or one number")
(5 flag boolean boolean
(lambda (pl) '(#f)) #f "a boolean flag")))
'(foo-pnames
((name string))
((parameter-index uint))
(("s" 1)
("single-string" 1)
("n" 2)
("nary-symbols" 2)
("N" 3)
("nary1-symbols" 3)
("o" 4)
("optional-number" 4)
("f" 5)
("flag" 5)))
'(my-commands
((name symbol))
((parameters parameter-list)
(parameter-names parameter-name-translation)
(procedure expression)
(documentation string))
((foo
foo-params
foo-pnames
(lambda (rdb) (lambda args (print args)))
"test command arguments"))))
(define (dbutil:serve-command-line rdb command-table
command argc argv)
(set! argv (if (vector? argv) (vector->list argv) argv))
((make-command-server rdb command-table)
command
(lambda (comname comval options positions
arities types defaulters dirs aliases)
(apply comval (getopt->arglist
argc argv options positions
arities types defaulters dirs aliases)))))
(define (cmd . opts)
(fluid-let ((*optind* 1))
(printf "%-34s => "
(call-with-output-string (lambda (pt) (write (cons 'cmd opts) pt)))
;;(apply string-append (map (lambda (x) (string-append x " ")) opts))
)
(set! opts (cons "cmd" opts))
(force-output)
(dbutil:serve-command-line
my-rdb 'my-commands 'foo (length opts) opts)))
(cmd) => ("str" () (symb) () #f)
(cmd "-f") => ("str" () (symb) () #t)
(cmd "--flag") => ("str" () (symb) () #t)
(cmd "-o177") => ("str" () (symb) (177) #f)
(cmd "-o" "177") => ("str" () (symb) (177) #f)
(cmd "--optional" "621") => ("str" () (symb) (621) #f)
(cmd "--optional=621") => ("str" () (symb) (621) #f)
(cmd "-s" "speciality") => ("speciality" () (symb) () #f)
(cmd "-sspeciality") => ("speciality" () (symb) () #f)
(cmd "--single" "serendipity") => ("serendipity" () (symb) () #f)
(cmd "--single=serendipity") => ("serendipity" () (symb) () #f)
(cmd "-n" "gravity" "piety") => ("str" () (piety gravity) () #f)
(cmd "-ngravity" "piety") => ("str" () (piety gravity) () #f)
(cmd "--nary" "chastity") => ("str" () (chastity) () #f)
(cmd "--nary=chastity" "") => ("str" () ( chastity) () #f)
(cmd "-N" "calamity") => ("str" () (calamity) () #f)
(cmd "-Ncalamity") => ("str" () (calamity) () #f)
(cmd "--nary1" "surety") => ("str" () (surety) () #f)
(cmd "--nary1=surety") => ("str" () (surety) () #f)
(cmd "-N" "levity" "fealty") => ("str" () (fealty levity) () #f)
(cmd "-Nlevity" "fealty") => ("str" () (fealty levity) () #f)
(cmd "--nary1" "surety" "brevity") => ("str" () (brevity surety) () #f)
(cmd "--nary1=surety" "brevity") => ("str" () (brevity surety) () #f)
(cmd "-?")
-|
Usage: cmd [OPTION ARGUMENT ...] ...
-f, --flag
-o, --optional[=]<number>
-n, --nary[=]<symbols> ...
-N, --nary1[=]<symbols> ...
-s, --single[=]<string>
ERROR: getopt->parameter-list "unrecognized option" "-?"
Some commands are defined in all extended relational-databases. The are called just like section Relational Database Operations.
(car domain-row) and
returns #t. Otherwise returns #f.
For the fields and layout of the domain table, See section Catalog Representation. Currently, these fields are
The following example adds 3 domains to the `build' database.
`Optstring' is either a string or #f. filename is a
string and build-whats is a symbol.
(for-each (build 'add-domain)
'((optstring #f
(lambda (x) (or (not x) (string? x)))
string
#f)
(filename #f #f string #f)
(build-whats #f #f symbol #f)))
(<name> <descriptor-name> <descriptor-name> <rows>)
or
(<name> <primary-key-fields> <other-fields> <rows>)
where <name> is the table name, <descriptor-name> is the symbol name of a descriptor table, <primary-key-fields> and <other-fields> describe the primary keys and other fields respectively, and <rows> is a list of data rows to be added to the table.
<primary-key-fields> and <other-fields> are lists of field descriptors of the form:
(<column-name> <domain>)
or
(<column-name> <domain> <column-integrity-rule>)
where <column-name> is the column name, <domain> is the domain
of the column, and <column-integrity-rule> is an expression whose
value is a procedure of one argument (which returns #f to signal
an error).
If <domain> is not a defined domain name and it matches the name of this table or an already defined (in one of spec-0 ...) single key field table, a foriegn-key domain will be created for it.
*reports* in the relational database rdb.
destination is a port, string, or symbol. If destination is
a:
Each row in the table *reports* has the fields:
format string. At the beginning and end of each page
respectively, format is called with this string and the (list of)
column-names of this table.
format string. For each row in the table, format is
called with this string and the row.
0 if a row's lines should not be broken over page
boundaries.
Each row in the table *printers* has the fields:
The report is prepared as follows:
Format (see section Format (version 3.0)) is called with the header field
and the (list of) column-names of the table.
Format is called with the reporter field and (on
successive calls) each record in the natural order for the table. A
count is kept of the number of newlines output by format. When the
number of newlines to be output exceeds the number of lines per page,
the set of lines will be broken if there are more than
minimum-break left on this page and the number of lines for this
row is larger or equal to twice minimum-break.
Format is called with the footer field and the (list of)
column-names of the table. The footer field should not output a
newline.
The following example shows a new database with the name of `foo.db' being created with tables describing processor families and processor/os/compiler combinations.
The database command define-tables is defined to call
define-tables with its arguments. The database is also
configured to print `Welcome' when the database is opened. The
database is then closed and reopened.
(require 'database-utilities)
(define my-rdb (create-database "foo.db" 'alist-table))
(define-tables my-rdb
'(*commands*
((name symbol))
((parameters parameter-list)
(procedure expression)
(documentation string))
((define-tables
no-parameters
no-parameter-names
(lambda (rdb) (lambda specs (apply define-tables rdb specs)))
"Create or Augment tables from list of specs")
(*initialize*
no-parameters
no-parameter-names
(lambda (rdb) (display "Welcome") (newline) rdb)
"Print Welcome"))))
((my-rdb 'define-tables)
'(processor-family
((family atom))
((also-ran processor-family))
((m68000 #f)
(m68030 m68000)
(i386 8086)
(8086 #f)
(powerpc #f)))
'(platform
((name symbol))
((processor processor-family)
(os symbol)
(compiler symbol))
((aix powerpc aix -)
(amiga-dice-c m68000 amiga dice-c)
(amiga-aztec m68000 amiga aztec)
(amiga-sas/c-5.10 m68000 amiga sas/c)
(atari-st-gcc m68000 atari gcc)
(atari-st-turbo-c m68000 atari turbo-c)
(borland-c-3.1 8086 ms-dos borland-c)
(djgpp i386 ms-dos gcc)
(linux i386 linux gcc)
(microsoft-c 8086 ms-dos microsoft-c)
(os/2-emx i386 os/2 gcc)
(turbo-c-2 8086 ms-dos turbo-c)
(watcom-9.0 i386 ms-dos watcom))))
((my-rdb 'close-database))
(set! my-rdb (open-database "foo.db" 'alist-table))
-|
Welcome
Balanced binary trees are a useful data structure for maintaining large sets of ordered objects or sets of associations whose keys are ordered. MIT Scheme has an comprehensive implementation of weight-balanced binary trees which has several advantages over the other data structures for large aggregates:
(+ 1 x)
modifies neither the constant 1 nor the value bound to x. The
trees are referentially transparent thus the programmer need not worry
about copying the trees. Referential transparency allows space
efficiency to be achieved by sharing subtrees.
These features make weight-balanced trees suitable for a wide range of applications, especially those that require large numbers of sets or discrete maps. Applications that have a few global databases and/or concentrate on element-level operations like insertion and lookup are probably better off using hash-tables or red-black trees.
The size of a tree is the number of associations that it contains. Weight balanced binary trees are balanced to keep the sizes of the subtrees of each node within a constant factor of each other. This ensures logarithmic times for single-path operations (like lookup and insertion). A weight balanced tree takes space that is proportional to the number of associations in the tree. For the current implementation, the constant of proportionality is six words per association.
Weight balanced trees can be used as an implementation for either
discrete sets or discrete maps (associations). Sets are implemented by
ignoring the datum that is associated with the key. Under this scheme
if an associations exists in the tree this indicates that the key of the
association is a member of the set. Typically a value such as
(), #t or #f is associated with the key.
Many operations can be viewed as computing a result that, depending on
whether the tree arguments are to
thhe arities of each parameter. Corresponds to the
arity field of the command's parameter-table. For a
description of arity see table above.
type-id field of the contents of the domain of the
command's parameter-table.
defaulters field of the command's parameter-table.
nary arity
parameters.
(alias parameter-name). There can be
more than one alias per parameter-name.
For information about parameters, See section Parameter lists. Here is an
example of setting up a command with arguments and parsing those
arguments from a getopt style argument list (see section Getopt).
(require 'database-utilities)
(require 'fluid-let)
(require 'parameters)
(require 'getopt)
(define my-rdb (create-database #f 'alist-table))
(define-tables my-rdb
'(foo-params
*parameter-columns*
*parameter-columns*
((1 single-string single string
(lambda (pl) '("str")) #f "single string")
(2 nary-symbols nary symbol
(lambda (pl) '()) #f "zero or more symbols")
(3 nary1-symbols nary1 symbol
(lambda (pl) '(symb)) #f "one or more symbols")
(4 optional-number optional uint
(lambda (pl) '()) #f "zero or one number")
(5 flag boolean boolean
(lambda (pl) '(#f)) #f "a boolean flag")))
'(foo-pnames
((name string))
((parameter-index uint))
(("s" 1)
("single-string" 1)
("n" 2)
("nary-symbols" 2)
("N" 3)
("nary1-symbols" 3)
("o" 4)
("optional-number" 4)
("f" 5)
("flag" 5)))
'(my-commands
((name symbol))
((parameters parameter-list)
(parameter-names parameter-name-translation)
(procedure expression)
(documentation string))
((foo
foo-params
foo-pnames
(lambda (rdb) (lambda args (print args)))
"test command arguments"))))
(define (dbutil:serve-command-line rdb command-table
command argc argv)
(set! argv (if (vector? argv) (vector->list argv) argv))
((make-command-server rdb command-table)
command
(lambda (comname comval options positions
arities types defaulters dirs aliases)
(apply comval (getopt->arglist
argc argv options positions
arities types defaulters dirs aliases)))))
(define (cmd . opts)
(fluid-let ((*optind* 1))
(printf "%-34s => "
(call-with-output-string (lambda (pt) (write (cons 'cmd opts) pt)))
;;(apply string-append (map (lambda (x) (string-append x " ")) opts))
)
(set! opts (cons "cmd" opts))
(force-output)
(dbutil:serve-command-line
my-rdb 'my-commands 'foo (length opts) opts)))
(cmd) => ("str" () (symb) () #f)
(cmd "-f") => ("str" () (symb) () #t)
(cmd "--flag") => ("str" () (symb) () #t)
(cmd "-o177") => ("str" () (symb) (177) #f)
(cmd "-o" "177") => ("str" () (symb) (177) #f)
(cmd "--optional" "621") => ("str" () (symb) (621) #f)
(cmd "--optional=621") => ("str" () (symb) (621) #f)
(cmd "-s" "speciality") => ("speciality" () (symb) () #f)
(cmd "-sspeciality") => ("speciality" () (symb) () #f)
(cmd "--single" "serendipity") => ("serendipity" () (symb) () #f)
(cmd "--single=serendipity") => ("serendipity" () (symb) () #f)
(cmd "-n" "gravity" "piety") => ("str" () (piety gravity) () #f)
(cmd "-ngravity" "piety") => ("str" () (piety gravity) () #f)
(cmd "--nary" "chastity") => ("str" () (chastity) () #f)
(cmd "--nary=chastity" "") => ("str" () ( chastity) () #f)
(cmd "-N" "calamity") => ("str" () (calamity) () #f)
(cmd "-Ncalamity") => ("str" () (calamity) () #f)
(cmd "--nary1" "surety") => ("str" () (surety) () #f)
(cmd "--nary1=surety") => ("str" () (surety) () #f)
(cmd "-N" "levity" "fealty") => ("str" () (fealty levity) () #f)
(cmd "-Nlevity" "fealty") => ("str" () (fealty levity) () #f)
(cmd "--nary1" "surety" "brevity") => ("str" () (brevity surety) () #f)
(cmd "--nary1=surety" "brevity") => ("str" () (brevity surety) () #f)
(cmd "-?")
-|
Usage: cmd [OPTION ARGUMENT ...] ...
-f, --flag
-o, --optional[=]<number>
-n, --nary[=]<symbols> ...
-N, --nary1[=]<symbols> ...
-s, --single[=]<string>
ERROR: getopt->parameter-list "unrecognized option" "-?"
Some commands are defined in all extended relational-databases. The are called just like section Relational Database Operations.
(car domain-row) and
returns #t. Otherwise returns #f.
For the fields and layout of the domain table, See section Catalog Representation. Currently, these fields are
The following example adds 3 domains to the `build' database.
`Optstring' is either a string or #f. filename is a
string and build-whats is a symbol.
(for-each (build 'add-domain)
'((optstring #f
(lambda (x) (or (not x) (string? x)))
string
#f)
(filename #f #f string #f)
(build-whats #f #f symbol #f)))
(<name> <descriptor-name> <descriptor-name> <rows>)
or
(<name> <primary-key-fields> <other-fields> <rows>)
where <name> is the table name, <descriptor-name> is the symbol name of a descriptor table, <primary-key-fields> and <other-fields> describe the primary keys and other fields respectively, and <rows> is a list of data rows to be added to the table.
<primary-key-fields> and <other-fields> are lists of field descriptors of the form:
(<column-name> <domain>)
or
(<column-name> <domain> <column-integrity-rule>)
where <column-name> is the column name, <domain> is the domain
of the column, and <column-integrity-rule> is an expression whose
value is a procedure of one argument (which returns #f to signal
an error).
If <domain> is not a defined domain name and it matches the name of this table or an already defined (in one of spec-0 ...) single key field table, a foriegn-key domain will be created for it.
*reports* in the relational database rdb.
destination is a port, string, or symbol. If destination is
a:
Each row in the table *reports* has the fields:
format string. At the beginning and end of each page
respectively, format is called with this string and the (list of)
column-names of this table.
format string. For each row in the table, format is
called with this string and the row.
0 if a row's lines should not be broken over page
boundaries.
Each row in the table *printers* has the fields:
The report is prepared as follows:
Format (see section Format (version 3.0)) is called with the header field
and the (list of) column-names of the table.
Format is called with the reporter field and (on
successive calls) each record in the natural order for the table. A
count is kept of the number of newlines output by format. When the
number of newlines to be output exceeds the number of lines per page,
the set of lines will be broken if there are more than
minimum-break left on this page and the number of lines for this
row is larger or equal to twice minimum-break.
Format is called with the footer field and the (list of)
column-names of the table. The footer field should not output a
newline.
The following example shows a new database with the name of `foo.db' being created with tables describing processor families and processor/os/compiler combinations.
The database command define-tables is defined to call
define-tables with its arguments. The database is also
configured to print `Welcome' when the database is opened. The
database is then closed and reopened.
(require 'database-utilities)
(define my-rdb (create-database "foo.db" 'alist-table))
(define-tables my-rdb
'(*commands*
((name symbol))
((parameters parameter-list)
(procedure expression)
(documentation string))
((define-tables
no-parameters
no-parameter-names
(lambda (rdb) (lambda specs (apply define-tables rdb specs)))
"Create or Augment tables from list of specs")
(*initialize*
no-parameters
no-parameter-names
(lambda (rdb) (display "Welcome") (newline) rdb)
"Print Welcome"))))
((my-rdb 'define-tables)
'(processor-family
((family atom))
((also-ran processor-family))
((m68000 #f)
(m68030 m68000)
(i386 8086)
(8086 #f)
(powerpc #f)))
'(platform
((name symbol))
((processor processor-family)
(os symbol)
(compiler symbol))
((aix powerpc aix -)
(amiga-dice-c m68000 amiga dice-c)
(amiga-aztec m68000 amiga aztec)
(amiga-sas/c-5.10 m68000 amiga sas/c)
(atari-st-gcc m68000 atari gcc)
(atari-st-turbo-c m68000 atari turbo-c)
(borland-c-3.1 8086 ms-dos borland-c)
(djgpp i386 ms-dos gcc)
(linux i386 linux gcc)
(microsoft-c 8086 ms-dos microsoft-c)
(os/2-emx i386 os/2 gcc)
(turbo-c-2 8086 ms-dos turbo-c)
(watcom-9.0 i386 ms-dos watcom))))
((my-rdb 'close-database))
(set! my-rdb (open-database "foo.db" 'alist-table))
-|
Welcome
Balanced binary trees are a useful data structure for maintaining large sets of ordered objects or sets of associations whose keys are ordered. MIT Scheme has an comprehensive implementation of weight-balanced binary trees which has several advantages over the other data structures for large aggregates:
(+ 1 x)
modifies neither the constant 1 nor the value bound to x. The
trees are referentially transparent thus the programmer need not worry
about copying the trees. Referential transparency allows space
efficiency to be achieved by sharing subtrees.
These features make weight-balanced trees suitable for a wide range of applications, especially those that require large numbers of sets or discrete maps. Applications that have a few global databases and/or concentrate on element-level operations like insertion and lookup are probably better off using hash-tables or red-black trees.
The size of a tree is the number of associations that it contains. Weight balanced binary trees are balanced to keep the sizes of the subtrees of each node within a constant factor of each other. This ensures logarithmic times for single-path operations (like lookup and insertion). A weight balanced tree takes space that is proportional to the number of associations in the tree. For the current implementation, the constant of proportionality is six words per association.
Weight balanced trees can be used as an implementation for either
discrete sets or discrete maps (associations). Sets are implemented by
ignoring the datum that is associated with the key. Under this scheme
if an associations exists in the tree this indicates that the key of the
association is a member of the set. Typically a value such as
(), #t or #f is associated with the key.
Many operations can be viewed as computing a result that, depending on
whether the tree arguments are to
thhe arities of each parameter. Corresponds to the
arity field of the command's parameter-table. For a
description of arity see table above.
type-id field of the contents of the domain of the
command's parameter-table.
defaulters field of the command's parameter-table.
nary arity
parameters.
(alias parameter-name). There can be
more than one alias per parameter-name.
For information about parameters, See section Parameter lists. Here is an
example of setting up a command with arguments and parsing those
arguments from a getopt style argument list (see section Getopt).
(require 'database-utilities)
(require 'fluid-let)
(require 'parameters)
(require 'getopt)
(define my-rdb (create-database #f 'alist-table))
(define-tables my-rdb
'(foo-params
*parameter-columns*
*parameter-columns*
((1 single-string single string
(lambda (pl) '("str")) #f "single string")
(2 nary-symbols nary symbol
(lambda (pl) '()) #f "zero or more symbols")
(3 nary1-symbols nary1 symbol
(lambda (pl) '(symb)) #f "one or more symbols")
(4 optional-number optional uint
(lambda (pl) '()) #f "zero or one number")
(5 flag boolean boolean
(lambda (pl) '(#f)) #f "a boolean flag")))
'(foo-pnames
((name string))
((parameter-index uint))
(("s" 1)
("single-string" 1)
("n" 2)
("nary-symbols" 2)
("N" 3)
("nary1-symbols" 3)
("o" 4)
("optional-number" 4)
("f" 5)
("flag" 5)))
'(my-commands
((name symbol))
((parameters parameter-list)
(parameter-names parameter-name-translation)
(procedure expression)
(documentation string))
((foo
foo-params
foo-pnames
(lambda (rdb) (lambda args (print args)))
"test command arguments"))))
(define (dbutil:serve-command-line rdb command-table
command argc argv)
(set! argv (if (vector? argv) (vector->list argv) argv))
((make-command-server rdb command-table)
command
(lambda (comname comval options positions
arities types defaulters dirs aliases)
(apply comval (getopt->arglist
argc argv options positions
arities types defaulters dirs aliases)))))
(define (cmd . opts)
(fluid-let ((*optind* 1))
(printf "%-34s => "
(call-with-output-string (lambda (pt) (write (cons 'cmd opts) pt)))
;;(apply string-append (map (lambda (x) (string-append x " ")) opts))
)
(set! opts (cons "cmd" opts))
(force-output)
(dbutil:serve-command-line
my-rdb 'my-commands 'foo (length opts) opts)))
(cmd) => ("str" () (symb) () #f)
(cmd "-f") => ("str" () (symb) () #t)
(cmd "--flag") => ("str" () (symb) () #t)
(cmd "-o177") => ("str" () (symb) (177) #f)
(cmd "-o" "177") => ("str" () (symb) (177) #f)
(cmd "--optional" "621") => ("str" () (symb) (621) #f)
(cmd "--optional=621") => ("str" () (symb) (621) #f)
(cmd "-s" "speciality") => ("speciality" () (symb) () #f)
(cmd "-sspeciality") => ("speciality" () (symb) () #f)
(cmd "--single" "serendipity") => ("serendipity" () (symb) () #f)
(cmd "--single=serendipity") => ("serendipity" () (symb) () #f)
(cmd "-n" "gravity" "piety") => ("str" () (piety gravity) () #f)
(cmd "-ngravity" "piety") => ("str" () (piety gravity) () #f)
(cmd "--nary" "chastity") => ("str" () (chastity) () #f)
(cmd "--nary=chastity" "") => ("str" () ( chastity) () #f)
(cmd "-N" "calamity") => ("str" () (calamity) () #f)
(cmd "-Ncalamity") => ("str" () (calamity) () #f)
(cmd "--nary1" "surety") => ("str" () (surety) () #f)
(cmd "--nary1=surety") => ("str" () (surety) () #f)
(cmd "-N" "levity" "fealty") => ("str" () (fealty levity) () #f)
(cmd "-Nlevity" "fealty") => ("str" () (fealty levity) () #f)
(cmd "--nary1" "surety" "brevity") => ("str" () (brevity surety) () #f)
(cmd "--nary1=surety" "brevity") => ("str" () (brevity surety) () #f)
(cmd "-?")
-|
Usage: cmd [OPTION ARGUMENT ...] ...
-f, --flag
-o, --optional[=]<number>
-n, --nary[=]<symbols> ...
-N, --nary1[=]<symbols> ...
-s, --single[=]<string>
ERROR: getopt->parameter-list "unrecognized option" "-?"
Some commands are defined in all extended relational-databases. The are called just like section Relational Database Operations.
(car domain-row) and
returns #t. Otherwise returns #f.
For the fields and layout of the domain table, See section Catalog Representation. Currently, these fields are