std::forward_list<T,Allocator>::splice_after
From cppreference.com
< cpp | container | forward list
void splice_after( const_iterator pos, forward_list& other ); |
(1) | (since C++11) (constexpr since C++26) |
void splice_after( const_iterator pos, forward_list&& other ); |
(2) | (since C++11) (constexpr since C++26) |
void splice_after( const_iterator pos, forward_list& other, const_iterator it ); |
(3) | (since C++11) (constexpr since C++26) |
void splice_after( const_iterator pos, forward_list&& other, const_iterator it ); |
(4) | (since C++11) (constexpr since C++26) |
void splice_after( const_iterator pos, forward_list& other, const_iterator first, const_iterator last ); |
(5) | (since C++11) (constexpr since C++26) |
void splice_after( const_iterator pos, forward_list&& other, const_iterator first, const_iterator last ); |
(6) | (since C++11) (constexpr since C++26) |
Transfers elements from other to *this. The elements are inserted after pos.
If any of the following conditions is satisfied, the behavior is undefined:
- pos is not in the range
(before_begin(),end()). - get_allocator() == other.get_allocator() is false.
1,2) Transfers all elements of other. other becomes empty after the operation.
If *this and other refer to the same object, the behavior is undefined.
3,4) Transfers the element following it.
*this and other can refer to the same object. In this case, there is no effect if pos == it or pos == ++it is true.
If ++it is not in the range
[begin(), end()), the behavior is undefined.5,6) Transfers elements in the range
(first, last). *this and other can refer to the same object.
If any of the following conditions is satisfied, the behavior is undefined:
-
(first,last)is not a valid range in other, - Any iterator in
(first,last)is not dereferenceable. - pos is in
(first,last).
No iterators or references become invalidated. If *this and other refer to different objects, the iterators to the transferred elements now refer into *this, not into other.
Contents |
[edit] Parameters
| pos | - | element after which the content will be inserted |
| other | - | another container to transfer the content from |
| it | - | iterator preceding the iterator to the element to transfer from other to *this |
| first, last | - | the pair of iterators defining the range of elements to transfer from other to *this |
[edit] Exceptions
1-4) Throws nothing.
[edit] Complexity
1,2) Linear in the size of other.
3,4) Constant.
5,6) Linear in std::distance(first, last).
[edit] Example
Run this code
#include <cassert> #include <forward_list> int main() { using F = std::forward_list<int>; // Demonstrate the meaning of open range (first, last) // in overload (5): the first element of l1 is not transferred. F l1 = {1, 2, 3, 4, 5}; F l2 = {10, 11, 12}; l2.splice_after(l2.cbegin(), l1, l1.cbegin(), l1.cend()); // Not equivalent to l2.splice_after(l2.cbegin(), l1); // which is equivalent to // l2.splice_after(l2.cbegin(), l1, l1.cbefore_begin(), l1.end()); assert((l1 == F{1})); assert((l2 == F{10, 2, 3, 4, 5, 11, 12})); // Overload (1) F x = {1, 2, 3, 4, 5}; F y = {10, 11, 12}; x.splice_after(x.cbegin(), y); assert((x == F{1, 10, 11, 12, 2, 3, 4, 5})); assert((y == F{})); // Overload (3) x = {1, 2, 3, 4, 5}; y = {10, 11, 12}; x.splice_after(x.cbegin(), y, y.cbegin()); assert((x == F{1, 11, 2, 3, 4, 5})); assert((y == F{10, 12})); // Overload (5) x = {1, 2, 3, 4, 5}; y = {10, 11, 12}; x.splice_after(x.cbegin(), y, y.cbegin(), y.cend()); assert((x == F{1, 11, 12, 2, 3, 4, 5})); assert((y == F{10})); }
[edit] Defect reports
The following behavior-changing defect reports were applied retroactively to previously published C++ standards.
| DR | Applied to | Behavior as published | Correct behavior |
|---|---|---|---|
| LWG 2045 | C++11 | O(1) splicing could not be guaranteed if get_allocator() != other.get_allocator() |
the behavior is undefined in this case |
| LWG 2222 | C++11 | the element pointed to by it is not transferred, but pointers, references and iterators referring to it would refer to an element in *this after splicing |
still refer to the element in other |
[edit] See also
| merges two sorted lists (public member function) | |
| removes elements satisfying specific criteria (public member function) | |
| returns an iterator to the element before beginning (public member function) |
