std::forward_list<T,Allocator>:: splice_after

Moves elements from another forward_list to * this . The elements are inserted after the element pointed to by pos .

No elements are copied. No iterators or references become invalidated. The iterators to the moved elements now refer into * this , not into other .

The behavior is undefined if

• get_allocator ( ) ! = other. get_allocator ( ) ,
• pos is neither before_begin ( ) nor a dereferenceable iterator in [ begin ( ) , end ( ) ) ,
• for overloads (1,2) , * this and other refer to the same object,
• for overloads (3,4) , the iterator following it is not a dereferenceable iterator into other , or
• for overloads (5,6) ,

• ( first , last ) is not a valid range in other ,
• some iterators in ( first , last ) are not dereferenceable , or
• pos is in ( first , last ) .

Parameters

Exceptions

Throws nothing.

Complexity

Example

#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 moved.
    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}));
}

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

See also