std::construct_at

 

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Defined in header <memory>
template<class T, class... Args> constexpr T* construct_at( T* p, Args&&... args );		(since C++20)

Creates a T object initialized with arguments args... at given address p. This overload only participates in overload resolution if ::new(std::declval<void*>()) T(std::declval<Args>()...) is well-formed in unevaluated context.

Equivalent to

return ::new (const_cast<void*>(static_cast<const volatile void*>(p)))
    T(std::forward<Args>(args)...);

except that construct_at may be used in evaluation of constant expressions.

When construct_at is called in the evaluation of some constant expression e, the argument p must point to either storage obtained by std::allocator<T>::allocate or an object whose lifetime began within the evaluation of e.

Parameters

p	-	pointer to the uninitialized storage on which a T object will be constructed
args...	-	arguments used for initialization

Return value

p

See also

construct [static]	constructs an object in the allocated storage (function template)
destroy_at (C++17)	destroys an object at a given address (function template)