operator==(std::copyable_function)
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< cpp | utility | functional | copyable function
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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 . Empty wrappers (that is, wrappers without a target) compare equal, non-empty functions compare non-equal.
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> is an associated class of the arguments.
The != operator is synthesized from operator==.
Contents
[edit] Parameters
f
-
std::copyable_function to compare
[edit] Return value
!f.
[edit] Example
This section is incomplete
Reason: no example
Reason: no example