std::numeric_limits::has_quiet_NaN
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                    < cpp | types | numeric limits
                    
                                                            
                    | static const bool has_quiet_NaN; | (until C++11) | |
| static constexpr bool has_quiet_NaN; | (since C++11) | |
The value of std::numeric_limits<T>::has_quiet_NaN is true for all types T capable of representing the special value "Quiet Not-A-Number". This constant is meaningful for all floating-point types and is guaranteed to be true if std::numeric_limits<T>::is_iec559 == true.
[edit] Standard specializations
| T | value of std::numeric_limits<T>::has_quiet_NaN | 
| /* non-specialized */ | false | 
| bool | false | 
| char | false | 
| signed char | false | 
| unsigned char | false | 
| wchar_t | false | 
| char16_t | false | 
| char32_t | false | 
| short | false | 
| unsigned short | false | 
| int | false | 
| unsigned int | false | 
| long | false | 
| unsigned long | false | 
| long long | false | 
| unsigned long long | false | 
| float | usually true | 
| double | usually true | 
| long double | usually true | 
[edit] See also
| [static] | returns a quiet NaN value of the given floating-point type (public static member function) | 
| [static] | identifies floating-point types that can represent the special value "positive infinity" (public static member constant) | 
| [static] | identifies floating-point types that can represent the special value "signaling not-a-number" (NaN) (public static member constant) | 


