std::allocator_traits<Alloc>::destroy

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Memory management library

voidify

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Allocators

allocator
allocator_traits (C++11)
allocation_result (C++23)
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allocator_arg (C++11)
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uninitialized_copy
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uninitialized_default_construct (C++17)
uninitialized_value_construct (C++17)
destroy (C++17)
uninitialized_default_construct_n (C++17)
uninitialized_value_construct_n (C++17)
destroy_n (C++17)
destroy_at (C++17)

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ranges::uninitialized_copy (C++20)
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ranges::uninitialized_default_construct (C++20)
ranges::uninitialized_value_construct (C++20)
ranges::destroy (C++20)
ranges::uninitialized_default_construct_n (C++20)
ranges::uninitialized_value_construct_n (C++20)
ranges::destroy_n (C++20)
ranges::destroy_at (C++20)

Memory resources

pmr::memory_resource (C++17)
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pmr::null_memory_resource (C++17)
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(C++11)

(C++11)

(until C++17*)

(C++11)

(C++17)

(C++26)

(C++26)

enable_shared_from_this

(C++11)

(C++11)

(C++11)

(C++23)

(C++23)

(C++11)

(C++20)

(C++11)

(C++11)

(C++20)

is_sufficiently_aligned

(C++26)

C Library

malloc
calloc
realloc

free
aligned_alloc (C++17)

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std::allocator_traits

Member types
Member functions
allocator_traits::allocate
allocator_traits::allocate_at_least (C++23)
allocator_traits::deallocate
allocator_traits::construct
allocator_traits::destroy
allocator_traits::max_size
allocator_traits::select_on_container_copy_construction

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Defined in header`<memory>`
template<class T> staticvoid destroy( Alloc& a, T* p);		(since C++11) (constexpr since C++20)

Calls the destructor of the object pointed to byp. If possible, does so by callinga.destroy(p). If not possible (e.g.Alloc does not have the member functiondestroy()), then callsthe destructor of*p directly, asp->~T()(until C++20)std::destroy_at(p)(since C++20).

[edit]Parameters

a	-	allocator to use for destruction
p	-	pointer to the object being destroyed

[edit]Return value

(none)

[edit]Notes

Because this function provides the automatic fall back to direct call to the destructor, the member functiondestroy() is an optionalAllocator requirement since C++11.