[/
 /  Copyright 2017 Peter Dimov
 /
 / Distributed under the Boost Software License, Version 1.0. (See
 / accompanying file LICENSE_1_0.txt or copy at
 / http://www.boost.org/LICENSE_1_0.txt)
 /]

[section:map Map Operations, `<boost/mp11/map.hpp>`]

A map is a list of lists, the inner lists having at least one element (the key.) The keys of the map must be unique.

[section `mp_map_find<M, K>`]
    template<class M, class K> using mp_map_find = /*...*/;

`mp_map_find<M, K>` is an alias for the element of the map `M` with a key `K`, or for `void`, if there is no such element.
[endsect]

[section `mp_map_contains<M, K>`]
    template<class M, class K> using mp_map_contains = mp_not<std::is_same<mp_map_find<M, K>, void>>;

`mp_map_contains<M, K>` is `mp_true` if the map `M` contains an element with a key `K`, `mp_false` otherwise.
[endsect]

[section `mp_map_insert<M, T>`]
    template<class M, class T> using mp_map_insert = mp_if< mp_map_contains<M, mp_first<T>>, M, mp_push_back<M, T> >;

Inserts the element `T` into the map `M`, if an element with a key `mp_first<T>` is not already in `M`.
[endsect]

[section `mp_map_replace<M, T>`]
    template<class M, class T> using mp_map_replace = /*...*/;

If the map `M` does not contain an element with a key `mp_first<T>`, inserts it (using `mp_push_back<M, T>`); otherwise,
replaces the existing element with `T`.
[endsect]

[section `mp_map_update<M, T, F>`]
    template<class M, class T, template<class...> class F> using mp_map_update = /*...*/;

If the map `M` does not contain an element with a key `mp_first<T>`, inserts it (using `mp_push_back<M, T>`); otherwise,
replaces the existing element `L<X, Y...>` with `L<X, F<X, Y...>>`.
[endsect]

[section `mp_map_erase<M, K>`]
    template<class M, class K> using mp_map_erase = /*...*/;

If the map `M` contains an element with a key `K`, removes it.
[endsect]

[endsect:map]