std::ranges::take_while_view<V,Pred>:: begin

constexpr auto begin ( ) requires ( ! /*simple-view*/ < V > ) ;	(1)	(since C++20)
constexpr auto begin ( ) const requires ranges:: range < const V > && std:: indirect_unary_predicate < const Pred, ranges:: iterator_t < const V >> ;	(2)	(since C++20)

Returns an iterator to the first element of the view. Effectively calls ranges:: begin on the underlying view base_ .

Overload (1) does not participate in overload resolution if V is a simple view (that is, if V and const V are views with the same iterator and sentinel types).

Parameters

(none)

Return value

ranges:: begin ( base_ ) , where base_ is the underlying view.

Example

This section is incomplete Reason: no example

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR	Applied to	Behavior as published	Correct behavior
LWG 3450	C++20	the const overload might return an iterator non-comparable to the sentinel	constrained

See also

end	returns a sentinel representing the end (public member function)
operator== (C++20)	compares a sentinel with an iterator returned from take_while_view::begin (function)