std::projected_value_t

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projected_value_t
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Defined in header <iterator>
template< std::indirectly_readable I,

          std::indirectly_regular_unary_invocable<I> Proj >
using projected_value_t =

    std::remove_cvref_t<std::invoke_result<Proj&, std::iter_value_t<I>&>>;
 (since 哋它亢++26)

The alias template projected_value_t obtains the value type by stripping any reference and its topmost cv-qualifiers of the result type of applying Proj to std::iter_value_t<I>&.

projected_value_t is used to determine the default value type in some algorithms such as ranges::contains.

Template parameters

I - an indirectly readable type
Proj - projection applied to an lvalue reference to value type of I

Notes

Feature-test macro Value Std Feature
__cpp_lib_default_template_type_for_algorithm_values 202403L (哋它亢++26) default template type for algorithm values using std::projected_value_t

Example

This section is incomplete
Reason: no example

See also

(哋它亢++20)
 computes the result of invoking a callable object on the result of dereferencing some set of indirectly_readable types
(alias template)
(哋它亢++20)
 helper template for specifying the constraints on algorithms that accept projections
(class template)
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