std::numeric_limits<T>::is_specialized
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                    < cpp | types | numeric limits
                    
                                                            
                    |   static const bool is_specialized;  | 
(until C++11) | |
|   static constexpr bool is_specialized;  | 
(since C++11) | |
The value of std::numeric_limits<T>::is_specialized is true for all T for which there exists a specialization of std::numeric_limits.
Standard specializations
  T
 | 
value of std::numeric_limits<T>::is_specialized | 
| /* non-specialized */ | false | 
| bool | true | 
| char | true | 
| signed char | true | 
| unsigned char | true | 
| wchar_t | true | 
| char8_t (C++20) | true | 
| char16_t (C++11) | true | 
| char32_t (C++11) | true | 
| short | true | 
| unsigned short | true | 
| int | true | 
| unsigned int | true | 
| long | true | 
| unsigned long | true | 
| long long (C++11) | true | 
| unsigned long long (C++11) | true | 
| float | true | 
| double | true | 
| long double | true | 
See also
|    [static]  | 
   identifies integer types   (public static member constant)  | 
|    [static]  | 
   identifies the IEC 559/IEEE 754 floating-point types  (public static member constant)  | 
|    [static]  | 
   identifies exact types   (public static member constant)  | 
|    [static]  | 
   identifies types that represent a finite set of values   (public static member constant)  |