__GNU_CXX::HASH_MULTIMAP(3)

💖 __gnu_cxx::hash_multimap 💖

okay bestie, welcome to the Library Functions Manual page for __gnu_cxx:...y, _Alloc >(3) — yes the title is literally truncated with an ellipsis, that's not me being lazy, that's just how it got rendered, and honestly? iconic. slay. let's get into it 🫶

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✨ NAME ✨

__gnu_cxx::hash_multimap< _Key, _Tp, _HashFn, _EqualKey, _Alloc >

that's the whole name. no notes. it's giving "template parameters went to a party and invited everyone" 💅

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🌈 SYNOPSIS 🌈

#include <hash_map>

that's your include. it lives in <hash_map>, not <unordered_map>, don't @ me, we'll get there. 🦋

🎀 Public Types 🎀

the glow-up glossary, lowkey:

• typedef _Ht::allocator_type allocator_type
• typedef _Ht::const_iterator const_iterator
• typedef _Ht::const_pointer const_pointer
• typedef _Ht::const_reference const_reference
• typedef _Tp data_type
• typedef _Ht::difference_type difference_type
• typedef _Ht::hasher hasher
• typedef _Ht::iterator iterator
• typedef _Ht::key_equal key_equal
• typedef _Ht::key_type key_type
• typedef _Tp mapped_type mapped_type — wait no, it's just typedef _Tp mapped_type, my bad, no cap 😭
• typedef _Ht::pointer pointer
• typedef _Ht::reference reference
• typedef _Ht::size_type size_type
• typedef _Ht::value_type value_type

🦋 Public Member Functions 🦋

the full roster, every single one, we do not skip, skipping is not the vibe:

• template<class _InputIterator> hash_multimap (_InputIterator __f, _InputIterator __l)
• template<class _InputIterator> hash_multimap (_InputIterator __f, _InputIterator __l, size_type __n)
• template<class _InputIterator> hash_multimap (_InputIterator __f, _InputIterator __l, size_type __n, const hasher &__hf)
• template<class _InputIterator> hash_multimap (_InputIterator __f, _InputIterator __l, size_type __n, const hasher &__hf, const key_equal &__eql, const allocator_type &__a=allocator_type())
• hash_multimap (size_type __n)
• hash_multimap (size_type __n, const hasher &__hf)
• hash_multimap (size_type __n, const hasher &__hf, const key_equal &__eql, const allocator_type &__a=allocator_type())
• iterator begin ()
• const_iterator begin () const
• size_type bucket_count () const
• void clear ()
• size_type count (const key_type &__key) const
• size_type elems_in_bucket (size_type __n) const
• bool empty () const
• iterator end ()
• const_iterator end () const
• pair< iterator, iterator > equal_range (const key_type &__key)
• pair< const_iterator, const_iterator > equal_range (const key_type &__key) const
• size_type erase (const key_type &__key)
• void erase (iterator __f, iterator __l)
• void erase (iterator __it)
• iterator find (const key_type &__key)
• const_iterator find (const key_type &__key) const
• allocator_type get_allocator () const
• hasher hash_funct () const
• template<class _InputIterator> void insert (_InputIterator __f, _InputIterator __l)
• iterator insert (const value_type &__obj)
• iterator insert_noresize (const value_type &__obj)
• key_equal key_eq () const
• size_type max_bucket_count () const
• size_type max_size () const
• void resize (size_type __hint)
• size_type size () const
• void swap (hash_multimap &__hs)

okay so like, three different erase overloads, two begin, two end, two find, two equal_range, a whole const situation — the duality of woman 💅✨

👑 Friends 👑

• template<class _K1, class _T1, class _HF, class _EqK, class _Al> bool operator== (const hash_multimap< _K1, _T1, _HF, _EqK, _Al > &, const hash_multimap< _K1, _T1, _HF, _EqK, _Al > &)

yes it's a friend. it's the friend that compares two whole hash_multimaps. bestie behavior fr fr. 🫶

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🔥 Detailed Description 🔥

template<class _Key, class _Tp, class _HashFn = hash<_Key>, class _EqualKey = equal_to<_Key>, class _Alloc = allocator<_Tp>>
class __gnu_cxx::hash_multimap< _Key, _Tp, _HashFn, _EqualKey, _Alloc >

so the template signature is right there, with _HashFn defaulting to hash<_Key>, _EqualKey defaulting to equal_to<_Key>, and _Alloc defaulting to allocator<_Tp>. defaults everywhere, we love a low-effort setup 💜

"This is an SGI extension."

that's a direct quote and it is VERY MUCH THE VIBE CHECK — this is an SGI extension, it is not standard C++, so don't be out here acting like it's plain portable code, iykyk. 🌸

😭 Todo 😭

literally the most relatable section of any manpage:

Needs documentation! See http://gcc.gnu.org/onlinedocs/libstdc++/manual/documentation_style.html

the page itself is telling on itself. it's giving "assignment not started, due tomorrow, main character energy". we respect the honesty though. 💀

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🌟 Author 🌟

Generated automatically by Doxygen for libstdc++ from the source code.

not a human, not a poet, just Doxygen doing its little thing. no cap.

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aaaand that's the page bestie!! 🎀 this was libstdc++'s page for __gnu_cxx:...y, _Alloc >(3), straight out of the Library Functions Manual, generated automatically by Doxygen for libstdc++ from the source code. go forth, use <hash_map>, remember it's an SGI extension, and hydrate. periodt. 💖✨🦋🌸👑🌈⭐💜