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std::ranges::equal_to(3)      C++ Standard Libary     std::ranges::equal_to(3)

NAME
       std::ranges::equal_to - std::ranges::equal_to

Synopsis
	  Defined in header <functional>
	  struct equal_to;		  (since C++20)

	  Function  object  for	performing comparisons.	The parameter types of
       the function call
	  operator (but	not the	return type) are deduced from the arguments.

Member functions
	  operator() checks if the arguments are equal
		     (public member function)

       std::ranges::equal_to::operator()

	  template< class T, class U >
	  constexpr bool operator()( T&& t, U&&	u ) const;

	  Given	the expression	std::forward<T>(t)  ==	std::forward<U>(u)  as
       expr:

	    *  If  expr	 results  in  a	 call to built-in operator== comparing
       pointers, given the
	      composite	pointer	type of	t and u	as P:

	    * For the two converted pointers (of type P), if one pointer  pre-
       cedes the other in
	      the implementation-defined strict	total order over pointers, re-
       turns false,
	      otherwise	returns	true.
	    *  If  the	conversion  sequence from T to P or the	conversion se-
       quence from U to	P is
	      not equality-preserving, the behavior is undefined.
	    * Otherwise:

	    * Returns the result of expr.
	    * If std::equality_comparable_with<T, U> is	not modeled,  the  be-
       havior is
	      undefined.

	  This overload	participates in	overload resolution only if
	  std::equality_comparable_with<T, U> is satisfied.

Notes
	  Compared  to	std::equal_to,	std::ranges::equal_to additionally re-
       quires != to be
	  valid, and that both argument	types  are  required  to  be  (homoge-
       neously)	comparable
	  with themselves (via the equality_comparable_with constraint).

Example
	   This	section	is incomplete
	   Reason: no example

	  Defect reports

	  The following	behavior-changing defect reports were applied retroac-
       tively to
	  previously published C++ standards.

	     DR	   Applied to	    Behavior as	published	       Correct
       behavior
	  LWG  3530 C++20      syntactic checks	were relaxed	 only semantic
       requirements are
			      while comparing pointers		relaxed

See also
	  equal_to function object implementing	x == y
		   (class template)

Category:
	    * Todo no example

http://cppreference.com		  2024.06.10	      std::ranges::equal_to(3)

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