operator==,!=(std::experimental::function)

 

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Defined in header <experimental/functional>
template< class R, class... ArgTypes > bool operator==( const std::experimental::function<R(ArgTypes...)>& f,                  std::nullptr_t ) noexcept;	(1)	(library fundamentals TS)
template< class R, class... ArgTypes > bool operator==( std::nullptr_t,                  const std::experimental::function<R(ArgTypes...)>& f ) noexcept;	(2)	(library fundamentals TS) (removed in library fundamentals TS v3)
template< class R, class... ArgTypes > bool operator!=( const std::experimental::function<R(ArgTypes...)>& f,                  std::nullptr_t ) noexcept;	(3)	(library fundamentals TS) (removed in library fundamentals TS v3)
template< class R, class... ArgTypes > bool operator!=( std::nullptr_t,                  const std::experimental::function<R(ArgTypes...)>& f ) noexcept;	(4)	(library fundamentals TS) (removed in library fundamentals TS v3)

Compares a std::experimental::function with a null pointer. Empty functions (that is, functions without a callable target) compare equal, non-empty functions compare non-equal.

The != operator is synthesized from operator==.

(library fundamentals TS v3)

Parameters

f

-

std::experimental::function to compare

Return value

1-2) !f

3-4) (bool) f

See also

operator==operator!= (removed in C++20)

compares a std::function with nullptr (function template)