std::experimental::ranges::identity

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< cpp‎ | experimental‎ | ranges
 
 
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struct identity;
(ranges TS)

ranges::identity is a function object type whose operator() returns its argument unchanged. It is used as the default projection for all Ranges TS algorithms.

Nested types

Nested type Definition
is_transparent unspecified

Member functions

operator()
returns the argument unchanged
(public member function)

std::experimental::ranges::identity::operator()

template< class T >
constexpr T&& operator()( T&& t ) const noexcept;

Returns std::forward<T>(t).

Parameters

t - argument to return

Return value

std::forward<T>(t).

Example