std::numeric_limits<T>::is_specialized

 

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std::numeric_limits

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numeric_limits::is_specialized

numeric_limits::is_signed

numeric_limits::is_integer

numeric_limits::is_exact

numeric_limits::has_infinity

numeric_limits::has_quiet_NaN

numeric_limits::has_signaling_NaN

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numeric_limits::signaling_NaN

numeric_limits::denorm_min

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staticconstbool is_specialized;		(until C++11)
staticconstexprbool 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
signedchar	true
unsignedchar	true
wchar_t	true
char8_t(since C++20)	true
char16_t(since C++11)	true
char32_t(since C++11)	true
short	true
unsignedshort	true
int	true
unsignedint	true
long	true
unsignedlong	true
longlong(since C++11)	true
unsignedlonglong(since C++11)	true
float	true
double	true
longdouble	true

Example

Run this code

#include <iostream>#include <limits>#include <type_traits>   int main(){enum E{};   std::cout<<std::boolalpha<<std::numeric_limits<bool>::is_specialized<<'\n'<<std::numeric_limits<longlong>::is_specialized<<'\n'<<std::numeric_limits<std::true_type>::is_specialized<<'\n'<<std::numeric_limits<E>::is_specialized<<'\n';}

Possible output:

true true false false

See also

is_integer [static]	identifies integer types (public static member constant)
is_iec559 [static]	identifies the IEC 559/IEEE 754 floating-point types (public static member constant)
is_exact [static]	identifies exact types (public static member constant)
is_bounded [static]	identifies types that represent a finite set of values (public static member constant)