public member function
<forward_list>

std::forward_list::clear

void clear() noexcept;
Clear content
Removes all elements from the forward_list container (which are destroyed), and leaving the container 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 << '\n';

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

  std::cout << "mylist contains:";
  for (int& x: mylist) std::cout << ' ' << x;
  std::cout << '\n';

  return 0;
}


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

Complexity

Linear in size (destructions).

Iterator validity

All iterators, references and pointers related to this container are invalidated, except the end iterators.

Data races

The container is modified.
All contained elements are modified.

Exception safety

No-throw guarantee: this member function never throws exceptions.

See also

  • 9316991614 2018-02-25
  • 191841613 2018-02-25
  • 16411612 2018-02-25
  • 6081981611 2018-02-25
  • 1784561610 2018-02-25
  • 4651609 2018-02-25
  • 9348111608 2018-02-25
  • 2513771607 2018-02-25
  • 6478461606 2018-02-24
  • 4985791605 2018-02-24
  • 5637141604 2018-02-24
  • 282181603 2018-02-24
  • 6217941602 2018-02-24
  • 5076141601 2018-02-24
  • 714281600 2018-02-24
  • 6607141599 2018-02-24
  • 949041598 2018-02-24
  • 6809961597 2018-02-24
  • 671871596 2018-02-24
  • 7107821595 2018-02-24