From cppreference.com
Specifies that an object of the type can be destroyed by a given
.
Requirements
Given the following types, values and expressions:
Type Definition Tan object type Aan allocator type Xa container type satisfying all following conditions: X::value_type is the same as T.
X::allocator_type is the same as std::allocator_traits<A>::rebind_alloc<T>.
Value Definition man lvalue of type Apa pointer of type T*If the expression std::allocator_traits<A>::destroy(m,p) is well-formed, T is Erasable from X.
Notes
All
require that their value types satisfy Erasable.
With the default allocator, this requirement is equivalent to the validity of p->~T(), which accepts class types with accessible destructors and all scalar types, but rejects array types, function types, reference types, and void.
(until C++20)With the default allocator, this requirement is equivalent to the validity of std::destroy_at(p), which accepts class types with accessible destructors and all scalar types, as well as arrays thereof.
(since C++20)Although it is required that customized destroy is used when destroying elements of
until C++23, all implementations only used the default mechanism. The requirement is corrected by
to match existing practice.
Defect reports
The following behavior-changing defect reports were applied retroactively to previously published C++ standards.
DR Applied to Behavior as published Correct behavior
C++11 there was no requirement to specify whether a type
whose objects can be destroyed using allocators added the requirement See also