std::experimental::ranges::projected
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< cpp | experimental | ranges
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projected
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Defined in header
<experimental/ranges/iterator>
template< Readable I, IndirectRegularUnaryInvocable<I> Proj >
(ranges TS)
struct projected {
using value_type =
std::remove_cv_t <std::remove_reference_t <ranges::indirect_result_of_t<Proj&(I)>>>;
ranges::indirect_result_of_t<Proj&(I)> operator*() const;
};
template< WeaklyIncrementable I, class Proj >
struct difference_type<projected <I, Proj>> {
using type = ranges::difference_type_t<I>;
The class template projected bundles a Readable type I and a function Proj into a new Readable type whose reference type is the result of applying Proj to the reference type of I. It exists solely to ease constraint specification, and so its operator*() may not be actually defined.