public member function
<forward_list>

std::forward_list::pop_front

void pop_front();
Delete first element
Removes the first element in the forward_list container, effectively reducing its size by one.

This destroys the removed element.

Parameters

none

Return value

none

Example

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// forward_list::pop_front
#include <iostream>
#include <forward_list>

int main ()
{
  std::forward_list<int> mylist = {10, 20, 30, 40};

  std::cout << "Popping out the elements in mylist:";
  while (!mylist.empty())
  {
    std::cout << ' ' << mylist.front();
    mylist.pop_front();
  }

  std::cout << '\n';

  return 0;
}

Output:
Popping out the elements in mylist: 10 20 30 40

Complexity

Constant.

Iterator validity

Iterators, pointers and references referring to element removed by the function are invalidated.
All other iterators, pointers and reference keep their validity.

Data races

The container is modified.
The first element is modified. Concurrently accessing or modifying other elements is safe.

Exception safety

If the container is not empty, the function never throws exceptions (no-throw guarantee).
Otherwise, it causes undefined behavior.

See also

forward_list::push_front
Insert element at beginning (public member function )
forward_list::emplace_front
Construct and insert element at beginning (public member function )
forward_list::remove
Remove elements with specific value (public member function )
forward_list::clear
Clear content (public member function )
forward_list::resize
Change size (public member function )

C++