Difference between revisions of "cpp/iterator/projected value t"
From cppreference.com
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===Notes=== | ===Notes=== | ||
| − | {{feature test macro| | + | {{feature test macro|__cpp_lib_algorithm_default_value_type|default template type for algorithm values using {{tt|std::projected_value_t}}|value=202403L|std=C++26}} |
===Example=== | ===Example=== | ||
Latest revision as of 14:42, 13 July 2024
| Defined in header <iterator>
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| template< std::indirectly_readable I, std::indirectly_regular_unary_invocable<I> Proj > |
(since C++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.
Contents |
[edit] Template parameters
| I | - | an indirectly readable type |
| Proj | - | projection applied to an lvalue reference to value type of I
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[edit] Notes
| Feature-test macro | Value | Std | Feature |
|---|---|---|---|
__cpp_lib_algorithm_default_value_type |
202403L | (C++26) | default template type for algorithm values using std::projected_value_t
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[edit] Example
| This section is incomplete Reason: no example |
[edit] See also
| (C++20) |
computes the result of invoking a callable object on the result of dereferencing some set of indirectly_readable types(alias template) |
| (C++20) |
helper template for specifying the constraints on algorithms that accept projections (class template) |
