STD::PMR_POLYMORPHIC_ALLOCATOR(3cxx)

💅 std::pmr::polymorphic_allocator< _Tp > — a.k.a. the libstdc++ (3cxx) page

okay so bestie, sit down, we're talking about std::pmr::polymorphic_allocator< _Tp > from the <memory_resource> world 💖 this is the class template polymorphic_allocator, and yes it's giving main character energy in the C++17 polymorphism scene.

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✨ NAME ✨

std::pmr::polymorphic_allocator< _Tp > — Class template polymorphic_allocator. that's it, that's the name, no cap 🎀

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🦋 SYNOPSIS 🦋

#include <memory_resource>

🌸 Public Types 🌸

• using value_type = _Tp — the type it allocates, literally the whole personality 🫶

💜 Public Member Functions 💜

• polymorphic_allocator (const polymorphic_allocator &__other)=default — copy constructor, defaulted, doing exactly what you'd expect, iconic
• template<typename _Up > polymorphic_allocator (const polymorphic_allocator< _Up > &__x) noexcept — converting constructor from another polymorphic_allocator< _Up >, and it's noexcept so it will not be dramatic about it
• polymorphic_allocator (memory_resource *__r) noexcept — build one from a memory_resource *__r, also noexcept 👑
• _Tp * allocate (size_t __n) — gimme __n of _Tp, hands you a _Tp * ✨
• void * allocate_bytes (size_t __nbytes, size_t __alignment=alignof(max_align_t)) — raw bytes mode, __nbytes of them, with __alignment defaulting to alignof(max_align_t)
• template<typename _Up > _Up * allocate_object (size_t __n=1) — allocates _Up objects, __n defaults to 1 (you get one, bestie 🎁)
• template<typename _Tp1 , typename... _Args> void construct (_Tp1 *__p, _Args &&... __args) — constructs at __p with __args..., the classic
• void deallocate (_Tp *__p, size_t __n) noexcept — gives back __n of _Tp at __p, noexcept, no tears
• void deallocate_bytes (void *__p, size_t __nbytes, size_t __alignment=alignof(max_align_t)) — returns raw bytes: pointer __p, __nbytes, __alignment defaulting to alignof(max_align_t)
• template<typename _Up > void deallocate_object (_Up *__p, size_t __n=1) — gives back __n _Up objects at __p, __n defaults to 1
• template<typename _Up > void delete_object (_Up *__p) — destroys and deallocates the _Up at __p in one lil move 💅
• template<typename _Up > void destroy (_Up *__p) — just destroys the _Up at __p, nothing more
• template<typename _Up , typename... _CtorArgs> _Up * new_object (_CtorArgs &&... __ctor_args) — allocates and constructs a _Up from __ctor_args..., a whole combo meal 🍓
• polymorphic_allocator & operator= (const polymorphic_allocator &)=delete — assignment is deleted. yes bestie, it's gone, you cannot assign, that's not a bug that's the design 🙈
• memory_resource * resource () const noexcept — hands you the memory_resource *, noexcept, the source of truth
• polymorphic_allocator select_on_container_copy_construction () const noexcept — the special copy-construction hook, noexcept, returns a polymorphic_allocator

🧚 Friends 🧚

• bool operator== (const polymorphic_allocator &__a, const polymorphic_allocator &__b) noexcept — compares two of these bad boys, noexcept, returns bool 🌈

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🔥 Detailed Description 🔥

template<typename _Tp>
    class std::pmr::polymorphic_allocator< _Tp >

so the actual text is: "Class template polymorphic_allocator." — short, sweet, mysterious, we love a low-word-count legend 🎀

Since: C++17 ⭐ (yes, C++17, that's the era, that's the vibe)

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🫶 Author 🫶

Generated automatically by Doxygen for libstdc++ from the source code. not a human, just Doxygen doing its lil thing 🤖💖

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aaaand that's the page! 🦋 this gem came to you from libstdc++, the source is the source code itself, and the lovely Doxygen generated it — big thank you to the std::pmr::polymorphic_allocator< _Tp >(3cxx) manual page, mwah 💋 periodt.