std::forward_list<T,Allocator>::pop_front - cppreference.com (original) (raw)
| void pop_front(); | | (since C++11) (constexpr since C++26) | | ------------------ | | ------------------------------------- |
Removes the first element of the container.
| If empty() is true, the behavior is undefined. | (until C++26) |
|---|---|
| If empty() is true: If the implementation is hardened, a contract violation occurs. Moreover, if the contract-violation handler returns under “observe” evaluation semantic, the behavior is undefined. If the implementation is not hardened, the behavior is undefined. | (since C++26) |
References and iterators to the erased element are invalidated.
[edit] Complexity
Constant.
[edit] Example
#include #include int main() { std::forward_list chars{'A', 'B', 'C', 'D'}; for (; !chars.empty(); chars.pop_front()) std::cout << "chars.front(): '" << chars.front() << "'\n"; }
Output:
chars.front(): 'A' chars.front(): 'B' chars.front(): 'C' chars.front(): 'D'
[edit] See also
| | inserts an element to the beginning (public member function) [edit] | | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | | access the first element (public member function) [edit] |