std::numeric_limits<T>::is_iec559

static const bool is_iec559;		(until C++11)
static constexpr bool is_iec559;		(since C++11)

The value of std::numeric_limits<T>::is_iec559 is true for all floating-point types T which fulfill the requirements of IEC 559 (IEEE 754) standard. If std::numeric_limits<T>::is_iec559 is true, then std::numeric_limits<T>::has_infinity, std::numeric_limits<T>::has_quiet_NaN, and std::numeric_limits<T>::has_signaling_NaN are also true.

`T`	value of `std::numeric_limits<T>::is_iec559`
/* non-specialized */	`false`
`bool`	`false`
`char`	`false`
`signed char`	`false`
`unsigned char`	`false`
`wchar_t`	`false`
`char8_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`

has_infinity [static]	identifies floating-point types that can represent the special value "positive infinity" (public static member constant)
has_quiet_NaN [static]	identifies floating-point types that can represent the special value "quiet not-a-number" (NaN) (public static member constant)
has_signaling_NaN [static]	identifies floating-point types that can represent the special value "signaling not-a-number" (NaN) (public static member constant)

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