__GNU_CXX::_EXTPTR_ALLOCATOR(3)

hey bestie! welcome to the __gnu_cxx::_ExtPtr_allocator< _Tp >(3) page from the Library Functions Manual 💖✨

💖 NAME 💖

okay so bestie, meet __gnu_cxx::_ExtPtr_allocator< _Tp > — an example allocator which uses a non-standard pointer type. it's giving "allocator but make it extra" 💅 no cap.

🦋 SYNOPSIS 🦋

to even get this party started, include the header like this:

#include <extptr_allocator.h>

✨ Public Types ✨

• typedef _Pointer_adapter< _Relative_pointer_impl< const _Tp > > const_pointer — the const pointer type, built from _Pointer_adapter< _Relative_pointer_impl< const _Tp > >. slay. 💖
• typedef const _Tp & const_reference — const ref to _Tp, simple. 🎀
• typedef std::ptrdiff_t difference_type — yep, std::ptrdiff_t is the difference type. ✨
• typedef _Pointer_adapter< _Relative_pointer_impl< _Tp > > pointer — the non-const pointer type, same _Pointer_adapter vibe but for _Tp. 🦋
• typedef _Tp & reference — ref to _Tp. 🌸
• typedef std::size_t size_type — size type is std::size_t. 💅
• typedef _Tp value_type — value type is _Tp. 👑

🫶 Public Member Functions 🫶

• _ExtPtr_allocator (const _ExtPtr_allocator &__rarg) noexcept — copy constructor from another _ExtPtr_allocator, and it's noexcept. 🫶
• template<typename _Up> _ExtPtr_allocator (const _ExtPtr_allocator< _Up > &__rarg) noexcept — converting constructor from _ExtPtr_allocator< _Up >, also noexcept. 💜
• const std::allocator< _Tp > & _M_getUnderlyingImp () const — returns the underlying std::allocator< _Tp > as a const ref. that's the one actually doing the memory work, per the detailed description. 🔥
• const_pointer address (const_reference __x) const noexcept — hands you the address of const __x as a const_pointer, noexcept. ✨
• pointer address (reference __x) const noexcept — hands you the address of __x as a pointer, noexcept. 🌈
• pointer allocate (size_type __n, const void *=0) — allocates __n things; the second param is const void * and defaults to 0. 👑
• template<typename _Up, typename... _Args> void construct (_Up *__p, _Args &&... __args) — constructs at _Up *__p using _Args &&... __args. 🎀
• template<typename... _Args> void construct (pointer __p, _Args &&... __args) — constructs at pointer __p using _Args &&... __args. 💖
• void deallocate (pointer __p, size_type __n) — deallocates __n things at pointer __p. 💅
• template<typename _Up> void destroy (_Up *__p) — destroys the thing at _Up *__p. 🌸
• void destroy (pointer __p) — destroys the thing at pointer __p. 🦋
• size_type max_size () const noexcept — returns max size as size_type, noexcept. ⭐
• bool operator== (const _ExtPtr_allocator &__rarg) const — equality check against another _ExtPtr_allocator. 💜
• template<typename _Up> bool operator== (const _ExtPtr_allocator< _Up > &__rarg) const — templated equality check against _ExtPtr_allocator< _Up >. 🔥

👑 Friends 👑

• template<typename _Up> void swap (_ExtPtr_allocator< _Up > &, _ExtPtr_allocator< _Up > &) — friend swap for two _ExtPtr_allocator< _Up > refs. iconic. 👑

🌈 Detailed Description 🌈

   template<typename _Tp>
       class __gnu_cxx::_ExtPtr_allocator< _Tp >

so basically this allocator specifies that containers use a 'relative pointer' as its pointer type. (See ext/pointer.h for the relative pointer tea.) Memory allocation in this example is still performed using std::allocator. periodt. 💅

🌸 Author 🌸

Generated automatically by Doxygen for libstdc++ from the source code. not me writing this by hand, Doxygen did it. 🤖✨

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that's the whole page bestie! source/version: libstdc++. date: not listed on the page. manual page: __gnu_cxx::_ExtPtr_allocator< _Tp >(3). bye 💖🦋🎀