operator==(std::copyable_function)

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(until C++17*)
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friend bool operator== ( const std::copyable_function & f, std::nullptr_t ) noexcept ;
(since C++26)

Checks whether the wrapper f has a callable target by formally comparing it with std::nullptr_t

This function is not visible to ordinary unqualified or qualified lookup, and can only be found by argument-dependent lookup when std::copyable_function<FunctionType>

The != operator is synthesized from operator==.

Parameters

f - std::copyable_function to compare

Return value

!f.

Example

See also

checks if the std::copyable_function has a target
(public member function)
(removed in C++20)
compares a std::function with nullptr
(function template)
(C++23)
compares a std::move_only_function with nullptr
(function)