- 1.8.0

  - The new ``IndexMap::into_keys`` and ``IndexMap::into_values`` will consume
    the map into keys or values, respectively, matching Rust 1.54's ``HashMap``
    methods, by @taiki-e in PR 195_.

  - More of the iterator types implement ``Debug``, ``ExactSizeIterator``, and
    ``FusedIterator``, by @cuviper in PR 196_.

  - ``IndexMap`` and ``IndexSet`` now implement rayon's ``ParallelDrainRange``,
    by @cuviper in PR 197_.

  - ``IndexMap::with_hasher`` and ``IndexSet::with_hasher`` are now ``const``
    functions, allowing static maps and sets, by @mwillsey in PR 203_.

  - ``IndexMap`` and ``IndexSet`` now implement ``From`` for arrays, matching
    Rust 1.56's implementation for ``HashMap``, by @rouge8 in PR 205_.

  - ``IndexMap`` and ``IndexSet`` now have methods ``sort_unstable_keys``,
    ``sort_unstable_by``, ``sorted_unstable_by``, and ``par_*`` equivalents,
    which sort in-place without preserving the order of equal items, by
    @bhgomes in PR 211_.

.. _195: https://github.com/bluss/indexmap/pull/195
.. _196: https://github.com/bluss/indexmap/pull/196
.. _197: https://github.com/bluss/indexmap/pull/197
.. _203: https://github.com/bluss/indexmap/pull/203
.. _205: https://github.com/bluss/indexmap/pull/205
.. _211: https://github.com/bluss/indexmap/pull/211

- 1.7.0

  - **MSRV**: Rust 1.49 or later is now required.

  - The ``hashbrown`` dependency has been updated to version 0.11.

- 1.6.2

  - Fixed to match ``std`` behavior, ``OccupiedEntry::key`` now references the
    existing key in the map instead of the lookup key, by @cuviper in PR 170_.

  - The new ``Entry::or_insert_with_key`` matches Rust 1.50's ``Entry`` method,
    passing ``&K`` to the callback to create a value, by @cuviper in PR 175_.

.. _170: https://github.com/bluss/indexmap/pull/170
.. _175: https://github.com/bluss/indexmap/pull/175

- 1.6.1

  - The new ``serde_seq`` module implements ``IndexMap`` serialization as a
    sequence to ensure order is preserved, by @cuviper in PR 158_.

  - New methods on maps and sets work like the ``Vec``/slice methods by the same name:
    ``truncate``, ``split_off``, ``first``, ``first_mut``, ``last``, ``last_mut``, and
    ``swap_indices``, by @cuviper in PR 160_.

.. _158: https://github.com/bluss/indexmap/pull/158
.. _160: https://github.com/bluss/indexmap/pull/160

- 1.6.0

  - **MSRV**: Rust 1.36 or later is now required.

  - The ``hashbrown`` dependency has been updated to version 0.9.

- 1.5.2

  - The new "std" feature will force the use of ``std`` for users that explicitly
    want the default ``S = RandomState``, bypassing the autodetection added in 1.3.0,
    by @cuviper in PR 145_.

.. _145: https://github.com/bluss/indexmap/pull/145

- 1.5.1

  - Values can now be indexed by their ``usize`` position by @cuviper in PR 132_.

  - Some of the generic bounds have been relaxed to match ``std`` by @cuviper in PR 141_.

  - ``drain`` now accepts any ``R: RangeBounds<usize>`` by @cuviper in PR 142_.

.. _132: https://github.com/bluss/indexmap/pull/132
.. _141: https://github.com/bluss/indexmap/pull/141
.. _142: https://github.com/bluss/indexmap/pull/142

- 1.5.0

  - **MSRV**: Rust 1.32 or later is now required.

  - The inner hash table is now based on ``hashbrown`` by @cuviper in PR 131_.
    This also completes the method ``reserve`` and adds ``shrink_to_fit``.

  - Add new methods ``get_key_value``, ``remove_entry``, ``swap_remove_entry``,
    and ``shift_remove_entry``, by @cuviper in PR 136_

  - ``Clone::clone_from`` reuses allocations by @cuviper in PR 125_

  - Add new method ``reverse`` by @linclelinkpart5 in PR 128_

.. _125: https://github.com/bluss/indexmap/pull/125
.. _128: https://github.com/bluss/indexmap/pull/128
.. _131: https://github.com/bluss/indexmap/pull/131
.. _136: https://github.com/bluss/indexmap/pull/136

- 1.4.0

  - Add new method ``get_index_of`` by @Thermatrix in PR 115_ and 120_

  - Fix build script rebuild-if-changed configuration to use "build.rs";
    fixes issue 123_. Fix by @cuviper.

  - Dev-dependencies (rand and quickcheck) have been updated. The crate's tests
    now run using Rust 1.32 or later (MSRV for building the crate has not changed).
    by @kjeremy and @bluss

.. _123: https://github.com/bluss/indexmap/issues/123
.. _115: https://github.com/bluss/indexmap/pull/115
.. _120: https://github.com/bluss/indexmap/pull/120

- 1.3.2

  - Maintenance update to regenerate the published `Cargo.toml`.

- 1.3.1

  - Maintenance update for formatting and ``autocfg`` 1.0.

- 1.3.0

  - The deprecation messages in the previous version have been removed.
    (The methods have not otherwise changed.) Docs for removal methods have been
    improved.
  - From Rust 1.36, this crate supports being built **without std**, requiring
    ``alloc`` instead. This is enabled automatically when it is detected that
    ``std`` is not available. There is no crate feature to enable/disable to
    trigger this. The new build-dep ``autocfg`` enables this.

- 1.2.0

  - Plain ``.remove()`` now has a deprecation message, it informs the user
    about picking one of the removal functions ``swap_remove`` and ``shift_remove``
    which have different performance and order semantics.
    Plain ``.remove()`` will not be removed, the warning message and method
    will remain until further.

  - Add new method ``shift_remove`` for order preserving removal on the map,
    and ``shift_take`` for the corresponding operation on the set.

  - Add methods ``swap_remove``, ``swap_remove_entry`` to ``Entry``.

  - Fix indexset/indexmap to support full paths, like ``indexmap::indexmap!()``

  - Internal improvements: fix warnings, deprecations and style lints

- 1.1.0

  - Added optional feature `"rayon"` that adds parallel iterator support
    to `IndexMap` and `IndexSet` using Rayon. This includes all the regular
    iterators in parallel versions, and parallel sort.

  - Implemented ``Clone`` for ``map::{Iter, Keys, Values}`` and
    ``set::{Difference, Intersection, Iter, SymmetricDifference, Union}``

  - Implemented ``Debug`` for ``map::{Entry, IntoIter, Iter, Keys, Values}`` and
    ``set::{Difference, Intersection, IntoIter, Iter, SymmetricDifference, Union}``

  - Serde trait ``IntoDeserializer`` are implemented for ``IndexMap`` and ``IndexSet``.

  - Minimum Rust version requirement increased to Rust 1.30 for development builds.

- 1.0.2

  - The new methods ``IndexMap::insert_full`` and ``IndexSet::insert_full`` are
    both like ``insert`` with the index included in the return value.

  - The new method ``Entry::and_modify`` can be used to modify occupied
    entries, matching the new methods of ``std`` maps in Rust 1.26.

  - The new method ``Entry::or_default`` inserts a default value in unoccupied
    entries, matching the new methods of ``std`` maps in Rust 1.28.

- 1.0.1

  - Document Rust version policy for the crate (see rustdoc)

- 1.0.0

  - This is the 1.0 release for ``indexmap``! (the crate and datastructure
    formerly known as “ordermap”)
  - ``OccupiedEntry::insert`` changed its signature, to use ``&mut self`` for
    the method receiver, matching the equivalent method for a standard
    ``HashMap``.  Thanks to @dtolnay for finding this bug.
  - The deprecated old names from ordermap were removed: ``OrderMap``,
    ``OrderSet``, ``ordermap!{}``, ``orderset!{}``. Use the new ``IndexMap``
    etc names instead.

- 0.4.1

  - Renamed crate to ``indexmap``; the ``ordermap`` crate is now deprecated
    and the types ``OrderMap/Set`` now have a deprecation notice.

- 0.4.0

  - This is the last release series for this ``ordermap`` under that name,
    because the crate is **going to be renamed** to ``indexmap`` (with types
    ``IndexMap``, ``IndexSet``) and no change in functionality!
  - The map and its associated structs moved into the ``map`` submodule of the
    crate, so that the map and set are symmetric

    + The iterators, ``Entry`` and other structs are now under ``ordermap::map::``

  - Internally refactored ``OrderMap<K, V, S>`` so that all the main algorithms
    (insertion, lookup, removal etc) that don't use the ``S`` parameter (the
    hasher) are compiled without depending on ``S``, which reduces generics bloat.

  - ``Entry<K, V>`` no longer has a type parameter ``S``, which is just like
    the standard ``HashMap``'s entry.

  - Minimum Rust version requirement increased to Rust 1.18

- 0.3.5

  - Documentation improvements

- 0.3.4

  - The ``.retain()`` methods for ``OrderMap`` and ``OrderSet`` now
    traverse the elements in order, and the retained elements **keep their order**
  - Added new methods ``.sort_by()``, ``.sort_keys()`` to ``OrderMap`` and
    ``.sort_by()``, ``.sort()`` to ``OrderSet``. These methods allow you to
    sort the maps in place efficiently.

- 0.3.3

  - Document insertion behaviour better by @lucab
  - Updated dependences (no feature changes) by @ignatenkobrain

- 0.3.2

  - Add ``OrderSet`` by @cuviper!
  - ``OrderMap::drain`` is now (too) a double ended iterator.

- 0.3.1

  - In all ordermap iterators, forward the ``collect`` method to the underlying
    iterator as well.
  - Add crates.io categories.

- 0.3.0

  - The methods ``get_pair``, ``get_pair_index`` were both replaced by
    ``get_full`` (and the same for the mutable case).
  - Method ``swap_remove_pair`` replaced by ``swap_remove_full``.
  - Add trait ``MutableKeys`` for opt-in mutable key access. Mutable key access
    is only possible through the methods of this extension trait.
  - Add new trait ``Equivalent`` for key equivalence. This extends the
    ``Borrow`` trait mechanism for ``OrderMap::get`` in a backwards compatible
    way, just some minor type inference related issues may become apparent.
    See `#10`__ for more information.
  - Implement ``Extend<(&K, &V)>`` by @xfix.

__ https://github.com/bluss/ordermap/pull/10

- 0.2.13

  - Fix deserialization to support custom hashers by @Techcable.
  - Add methods ``.index()`` on the entry types by @garro95.

- 0.2.12

  - Add methods ``.with_hasher()``, ``.hasher()``.

- 0.2.11

  - Support ``ExactSizeIterator`` for the iterators. By @Binero.
  - Use ``Box<[Pos]>`` internally, saving a word in the ``OrderMap`` struct.
  - Serde support, with crate feature ``"serde-1"``. By @xfix.

- 0.2.10

  - Add iterator ``.drain(..)`` by @stevej.

- 0.2.9

  - Add method ``.is_empty()`` by @overvenus.
  - Implement ``PartialEq, Eq`` by @overvenus.
  - Add method ``.sorted_by()``.

- 0.2.8

  - Add iterators ``.values()`` and ``.values_mut()``.
  - Fix compatibility with 32-bit platforms.

- 0.2.7

  - Add ``.retain()``.

- 0.2.6

  - Add ``OccupiedEntry::remove_entry`` and other minor entry methods,
    so that it now has all the features of ``HashMap``'s entries.

- 0.2.5

  - Improved ``.pop()`` slightly.

- 0.2.4

  - Improved performance of ``.insert()`` (`#3`__) by @pczarn.

__ https://github.com/bluss/ordermap/pull/3

- 0.2.3

  - Generalize ``Entry`` for now, so that it works on hashmaps with non-default
    hasher. However, there's a lingering compat issue since libstd ``HashMap``
    does not parameterize its entries by the hasher (``S`` typarm).
  - Special case some iterator methods like ``.nth()``.

- 0.2.2

  - Disable the verbose ``Debug`` impl by default.

- 0.2.1

  - Fix doc links and clarify docs.

- 0.2.0

  - Add more ``HashMap`` methods & compat with its API.
  - Experimental support for ``.entry()`` (the simplest parts of the API).
  - Add ``.reserve()`` (placeholder impl).
  - Add ``.remove()`` as synonym for ``.swap_remove()``.
  - Changed ``.insert()`` to swap value if the entry already exists, and
    return ``Option``.
  - Experimental support as an *indexed* hash map! Added methods
    ``.get_index()``, ``.get_index_mut()``, ``.swap_remove_index()``,
    ``.get_pair_index()``, ``.get_pair_index_mut()``.

- 0.1.2

  - Implement the 32/32 split idea for ``Pos`` which improves cache utilization
    and lookup performance.

- 0.1.1

  - Initial release.
