std::deque<T,Allocator>::pop_front
| void pop_front(); | 
Removes the first element of the container. If there are no elements in the container, the behavior is undefined.
| Iterators and references to the erased element are invalidated. It is unspecified whether the past-the-end iterator is invalidated if the element is the last element in the container. Other references and iterators are not affected. | (until C++11) | 
| Iterators and references to the erased element are invalidated. If the element is the last element in the container, the past-the-end iterator is also invalidated. Other references and iterators are not affected. | (since C++11) | 
Parameters
(none).
Return value
(none).
Complexity
Constant.
Exceptions
Does not throw.
See also
| removes the last element (public member function) | |
| inserts an element to the beginning (public member function) | 
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