Module Random: pseudo-random number generator

val initTLE>Module Pabound
in m, its previous binding disappears. 

    val find: key -> 'a t -> 'a


find x m returns the current binding of x in m,
or raises Not_found if no such binding exists. 

    val remove: key -> 'a t -> 'a t


remove x m returns a map containing the same bindings as
m, except for x which is unbound in the returned map. 

    val iter: (key -> 'a -> 'b) -> 'a t -> unit


iter f m applies f to all bindings in map m,
discarding the results.
f receives the key as first argument,