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std::numeric_limits::is_signed

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

The value of std::numeric_limits<T>::is_signed is true for all signed arithmetic types T and false for the unsigned types. This constant is meaningful for all specializations.

Standard specializations

`T`	value of `std::numeric_limits<T>::is_signed`
/* non-specialized */	`false`
`bool`	`false`
`char`	implementation-defined
`signed char`	`true`
`unsigned char`	`false`
`wchar_t`	implementation-defined
`char16_t`	`false`
`char32_t`	`false`
`short`	`true`
`unsigned short`	`false`
`int`	`true`
`unsigned int`	`false`
`long`	`true`
`unsigned long`	`false`
`long long`	`true`
`unsigned long long`	`false`
`float`	`true`
`double`	`true`
`long double`	`true`

is_signed (C++11)	checks if a type is signed integer type (class template)
is_integer [static]	identifies integer 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)

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std::numeric_limits::is_signed

std::numeric_limits::is_signed

Standard specializations

See also