cpp/ranges/view interface/front

The default implementation of member function returns the first element in the view of the derived type. Whether the element is returned by value or by reference depends on the of the iterator type.

@1@ Let be. Equivalent to. The behavior is undefined if is  (i.e. the beginning iterator compares equal to the sentinel), even if the iterator obtained in the same way is dereferenceable.

@2@ Same as, except that is.

Parameters
(none)

Return value
The first element in the view.