std::vector<T,Allocator>::insert_range

From cppreference.com
< cpp‎ | container‎ | vector

 
 
 
 
template< container-compatible-range<T> R >
constexpr iterator insert_range( const_iterator pos, R&& rg );
(since C++23)

Inserts, in non-reversing order, copies of elements in rg before pos.

If new size() is greater than capacity() the function causes reallocation, in which case all iterators (including the end() iterator) and references to the elements are invalidated. Otherwise, only the iterators and references before the insertion point remain valid.

Each iterator in the range rg is dereferenced exactly once.

The behavior is undefined if rg overlaps with the container.

Parameters

pos - iterator before which the content will be inserted (pos may be the end() iterator).
rg - a container compatible range, that is, an input_range whose elements are convertible to T.
Type requirements
-
T must be EmplaceConstructible into vector from *ranges::begin(rg). Also, T must be MoveInsertable into vector and T satisfies MoveConstructible, MoveAssignable, and Swappable. Otherwise, the behavior is undefined.

Return value

An iterator that points at the copy of the first element inserted into vector or at pos if rg is empty.

Notes

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

Example

#include <algorithm>
#include <cassert>
#include <iterator>
#include <vector>
#include <list>
 
int main()
{
    auto container = std::vector{1, 2, 3, 4};
    auto pos = std::next(container.begin(), 2);
    assert(*pos == 3);
    const auto rg = std::list{-1, -2, -3};
 
#ifdef __cpp_lib_containers_ranges
    container.insert_range(pos, rg);
#else
    container.insert(pos, rg.cbegin(), rg.cend());
#endif
    assert(std::ranges::equal(container, std::vector{1, 2, -1, -2, -3, 3, 4}));
}

See also

inserts elements
(public member function)
adds a range of elements to the end
(public member function)