std::ratio_not_equal
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                    |   Defined in header  <ratio>
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|   template< class R1, class R2 > struct ratio_not_equal : std::integral_constant<bool, /* see below */> { };  | 
(since C++11) | |
If the ratios R1 and R2 are not equal, provides the member constant value equal true. Otherwise, value is false.
Helper variable template
|   template< class R1, class R2 > constexpr bool ratio_not_equal_v = ratio_not_equal<R1, R2>::value;  | 
(since C++17) | |
Inherited from std::integral_constant
Member constants
|    value [static]  | 
   true if R1::num != R2::num || R1::den != R2::den, false otherwise   (public static member constant)  | 
Member functions
|    operator bool  | 
   converts the object to bool, returns value   (public member function)  | 
|    operator() (C++14)  | 
   returns value   (public member function)  | 
Member types
| Type | Definition | 
  value_type
 | 
bool | 
  type
 | 
std::integral_constant<bool, value> | 
Possible implementation
template< class R1, class R2 > struct ratio_not_equal : std::integral_constant < bool, !std::ratio_equal<R1, R2> > {};  | 
Example
Run this code
#include <ratio> static_assert(std::ratio_not_equal_v<std::ratio<6, 9>, std::ratio<9, 6>>, "6/9 != 9/6"); int main() {}
See also
|    (C++11)  | 
  compares two ratio objects for equality at compile-time (class template)  |