std::experimental::void_t

C++

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Language support library

Concepts library (C++20)

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Technical Specifications

Technical specifications

Filesystem library (filesystem TS)

Library fundamentals (library fundamentals TS)

Library fundamentals 2 (library fundamentals 2 TS)

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Extensions for parallelism 2 (parallelism TS v2)

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Library fundamentals v2

experimental::propagate_const

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detection idiom

uniform container erasure

logical operator type traits

Defined in header <experimental/type_traits>
template< class... > using void_t = void;		(library fundamentals TS v2)

A utility metafunction that maps a sequence of any types to the type void.

Notes

This utility metafunction is used in template metaprogramming to detect ill-formed types in SFINAE context. First voted into C++17 as std::void_t, it was later added as well to the library fundamentals TS as std::experimental::void_t, because it is a dependency of the detection idiom.

See also

void_t (C++17)

void variadic alias template (alias template)