std::numeric_limits<T>::is_specialized

 

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C numeric limits interface
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std::numeric_limits

Static constants

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

numeric_limits::has_denorm

numeric_limits::has_denorm_loss

numeric_limits::round_style

numeric_limits::is_iec559

numeric_limits::is_bounded

numeric_limits::is_modulo

numeric_limits::digits

numeric_limits::digits10

numeric_limits::max_digits10 (C++11)

numeric_limits::radix

numeric_limits::min_exponent

numeric_limits::min_exponent10

numeric_limits::max_exponent

numeric_limits::max_exponent10

numeric_limits::traps

numeric_limits::tinyness_before

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numeric_limits::min

numeric_limits::lowest (C++11)

numeric_limits::max

numeric_limits::epsilon

numeric_limits::round_error

numeric_limits::infinity

numeric_limits::quiet_NaN

numeric_limits::signaling_NaN

numeric_limits::denorm_min

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float_round_style

float_denorm_style

 

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 (since C++20)	true
char16_t (since C++11)	true
char32_t (since C++11)	true
short	true
unsigned short	true
int	true
unsigned int	true
long	true
unsigned long	true
long long (since C++11)	true
unsigned long long (since C++11)	true
float	true
double	true
long double	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<long long>::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)