std::ranges::not_equal_to

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plus<> (C++14)
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multiplies<> (C++14)
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bit_and<> (C++14)
bit_or<> (C++14)
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bit_xor<> (C++14)

equal_to<> (C++14)
not_equal_to<> (C++14)
greater<> (C++14)
less<> (C++14)
greater_equal<> (C++14)
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logical_and<> (C++14)
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ranges::equal_to (C++20)
ranges::not_equal_to (C++20)
ranges::greater (C++20)
ranges::less (C++20)
ranges::greater_equal (C++20)
ranges::less_equal (C++20)
compare_three_way (C++20)

Old binders and adaptors

unary_function (until C++17*)
binary_function (until C++17*)
ptr_fun (until C++17*)
pointer_to_unary_function (until C++17*)
pointer_to_binary_function (until C++17*)
mem_fun (until C++17*)
mem_fun_tmem_fun1_tconst_mem_fun_tconst_mem_fun1_t (until C++17)(until C++17)(until C++17)(until C++17)
not1 (until C++20*)
not2 (until C++20*)

binder1stbinder2nd (until C++17)(until C++17)
bind1stbind2nd (until C++17)(until C++17)

mem_fun_ref (until C++17*)
mem_fun_ref_tmem_fun1_ref_tconst_mem_fun_ref_tconst_mem_fun1_ref_t (until C++17)(until C++17)(until C++17)(until C++17)
unary_negate (until C++20*)
binary_negate (until C++20*)

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Defined in header`<functional>`
struct not_equal_to;		(since C++20)

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

[edit]Nested types

Nested type	Definition
`is_transparent`	unspecified

[edit]Member functions

operator()

checks if the arguments arenot equal
(public member function)

std::ranges::not_equal_to::operator()

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

Equivalent toreturn!ranges::equal_to{}(std::forward<T>(t),std::forward<U>(u));.

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

[edit]Notes

Unlikestd::not_equal_to,std::ranges::not_equal_to requires both== and!= to be valid (via theequality_comparable_with constraint), and is entirely defined in terms ofstd::ranges::equal_to.