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std::ranges::take_while_view<V,Pred>::begin - cppreference.com

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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

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