std::numeric_limits<T>::has_denorm

 

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static const std::float_denorm_style has_denorm;		(until C++11)
static constexpr std::float_denorm_style has_denorm;			(since C++11) (deprecated in C++23)

See More

The value of std::numeric_limits<T>::has_denorm identifies the floating-point types that support subnormal values.

Standard specializations

T	value of std::numeric_limits<T>::has_denorm
/* non-specialized */	std::denorm_absent
bool	std::denorm_absent
char	std::denorm_absent
signed char	std::denorm_absent
unsigned char	std::denorm_absent
wchar_t	std::denorm_absent
char8_t (since C++20)	std::denorm_absent
char16_t (since C++11)	std::denorm_absent
char32_t (since C++11)	std::denorm_absent
short	std::denorm_absent
unsigned short	std::denorm_absent
int	std::denorm_absent
unsigned int	std::denorm_absent
long	std::denorm_absent
unsigned long	std::denorm_absent
long long (since C++11)	std::denorm_absent
unsigned long long (since C++11)	std::denorm_absent
float	usually std::denorm_present
double	usually std::denorm_present
long double	usually std::denorm_present

Example

Run this code

#include <iostream>
#include <limits>
#include <string_view>

template<typename... T>
constexpr bool denorm_absent =
    ((std::numeric_limits<T>::has_denorm == std::denorm_absent) and ...);

static_assert(denorm_absent<
    bool, char, signed char, unsigned char, wchar_t, char8_t, char16_t, char32_t, short,
    unsigned short, int, unsigned int, long, unsigned long, long long, unsigned long long
>);

auto to_string(std::float_denorm_style e) -> std::string_view
{
    switch (e)
    {
        case std::denorm_indeterminate: return "denorm_indeterminate";
        case std::denorm_absent: return "denorm_absent";
        case std::denorm_present: return "denorm_present";
    }
    return "?";
}

int main()
{
    std::cout << to_string(std::numeric_limits<float>::has_denorm) << '\n';
}

Possible output:

denorm_present

See also

denorm_min [static]	returns the smallest positive subnormal value of the given floating-point type (public static member function)
float_denorm_style	indicates floating-point denormalization modes (enum)