std::experimental::ranges::projected - cppreference.com (original) (raw)

| | | | | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | ----------- | | template< Readable I, IndirectRegularUnaryInvocable<I> Proj > 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>; }; | | (ranges TS) |

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.