public member function

std::forward_list::clear

<forward_list>
void clear() noexcept;
Clear content
All the elements in the forward_list container are dropped: their destructors are called, and then they are removed from the forward_list container, leaving it with a size of 0.

Parameters

none

Return value

none

Example

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// clearing forward_list
#include <iostream>
#include <forward_list>

int main ()
{
  std::forward_list<int> mylist = { 10, 20, 30 };

  std::cout << "mylist contains:";
  for (int& x: mylist) std::cout << " " << x;
  std::cout << std::endl;

  mylist.clear();
  mylist.insert_after( mylist.before_begin(), {100, 200} );

  std::cout << "mylist contains:";
  for (int& x: mylist) std::cout << " " << x;
  std::cout << std::endl;

  return 0;
}


Output:
mylist contains: 10 20 30
mylist contains: 100 200

Complexity

Linear on size (destructors).

Iterator validity

All iterators, pointers and references are invalidated.

See also