__GNU_CXX::_EXTPTR_ALLOCATOR(3cxx)

🎀 NAME 🎀

okay bestie, welcome to the __gnu_cxx::_ExtPtr_allocator< _Tp >(3cxx) page — that's the __gnu_cxx manual, 3cxx section, and the class is __gnu_cxx::_ExtPtr_allocator< _Tp >. It's literally an example allocator which uses a non-standard pointer type. That's the whole assignment: allocator behavior, but the pointer type is doing a little extra. 💅

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✨ SYNOPSIS ✨

First things first, include this, no cap:

#include <extptr_allocator.h>

🌸 Public Types 🌸

Okay so the public typedefs are giving very structured, very "know your types" energy:

• const_pointer — typedef _Pointer_adapter< _Relative_pointer_impl< const _Tp > > const_pointer
• const_reference — typedef const _Tp & const_reference
• difference_type — typedef std::ptrdiff_t difference_type
• pointer — typedef _Pointer_adapter< _Relative_pointer_impl< _Tp > > pointer
• reference — typedef _Tp & reference
• size_type — typedef std::size_t size_type
• value_type — typedef _Tp value_type

💅 Public Member Functions 💅

Here's the whole function roster, bestie — every signature stays exactly as-is:

• same-type copy constructor, noexcept — _ExtPtr_allocator (const _ExtPtr_allocator &__rarg) noexcept
• templated converting copy constructor, noexcept — template<typename _Up > _ExtPtr_allocator (const _ExtPtr_allocator< _Up > &__rarg) noexcept
• underlying allocator peek — const std::allocator< _Tp > & _M_getUnderlyingImp () const
• const address — const_pointer address (const_reference __x) const noexcept
• non-const address — pointer address (reference __x) const noexcept
• allocate — pointer allocate (size_type __n, const void *=0)
• templated construct at _Up * — template<typename _Up , typename... _Args> void construct (_Up *__p, _Args &&... __args)
• construct at pointer — template<typename... _Args> void construct (pointer __p, _Args &&... __args)
• deallocate — void deallocate (pointer __p, size_type __n)
• templated destroy at _Up * — template<typename _Up > void destroy (_Up *__p)
• destroy at pointer — void destroy (pointer __p)
• max size — size_type max_size () const noexcept
• same-type equality compare — bool operator== (const _ExtPtr_allocator &__rarg) const
• templated equality compare — template<typename _Up > bool operator== (const _ExtPtr_allocator< _Up > &__rarg) const

🫶 Friends 🫶

Just one friend, and it's the swap bestie:

• swap — template<typename _Up > void swap (_ExtPtr_allocator< _Up > &, _ExtPtr_allocator< _Up > &)

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🔥 Detailed Description 🔥

The class template is exactly this:

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

And the official description is: "An example allocator which uses a non-standard pointer type." Iconic. This allocator specifies that containers use a 'relative pointer' as it's pointer type. (See ext/pointer.h.) Memory allocation in this example is still performed using std::allocator.

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💖 Author 💖

Generated automatically by Doxygen for libstdc++ from the source code. So yes, the author section is literally the Doxygen auto-gen credit. Respect. 🫶

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okay bye bestie 💜 source/version footer vibes: libstd__gnu_cxx::_Ex...llocator< _Tp >(3cxx) — that's the libstdc++ / 3cxx tag, and there's no separate date printed on the footer, so I'm not making one up. slay. ✨