std::ranges::destroy_n

Since C++20

Header: <memory>

Destroys the n objects in the range starting at first, equivalent to

# Declarations

Call signature

template< no-throw-input-iterator I >
requires std::destructible<std::iter_value_t<I>>
constexpr I destroy_n( I first, std::iter_difference_t<I> n ) noexcept;

(since C++20)

# Parameters

# Return value

The end of the range of objects that has been destroyed.

# Example

#include <iostream>
#include <memory>
#include <new>
 
struct Tracer
{
    int value;
    ~Tracer() { std::cout << value << " destructed\n"; }
};
 
int main()
{
    alignas(Tracer) unsigned char buffer[sizeof(Tracer) * 8];
 
    for (int i = 0; i < 8; ++i)
        new(buffer + sizeof(Tracer) * i) Tracer{i}; //manually construct objects
 
    auto ptr = std::launder(reinterpret_cast<Tracer*>(buffer));
 
    std::ranges::destroy_n(ptr, 8);
}

# See also