std::deque<T,Allocator>::prepend_range

Since C++23

Inserts, in non-reversing order, copies of elements in rg before begin(). Each iterator in the range rg is dereferenced exactly once.

# Declarations

template< container-compatible-range<T> R >
void prepend_range( R&& rg );

(since C++23)

# Parameters

# Return value

(none)

# Notes

Feature-test macro Value Std Feature __cpp_lib_containers_ranges 202202L (C++23) Ranges-aware construction and insertion

# Example

#include <algorithm>
#include <cassert>
#include <deque>
#include <vector>
 
int main()
{
    auto container = std::deque{0, 1, 2, 3};
    const auto rg = std::vector{-3, -2, -1};
 
#if __cpp_lib_containers_ranges
    container.prepend_range(rg);
#else
    container.insert(container.begin(), rg.cbegin(), rg.cend());
#endif
    assert(std::ranges::equal(container, std::deque{-3, -2, -1, 0, 1, 2, 3}));
}

# See also