is-signed-class.md

description	title	ms.date	f1_keywords	helpviewer_keywords	ms.assetid
Learn more about: is_signed Class	is_signed Class	11/04/2016	type_traits/std::is_signed	is_signed class is_signed	20ae44d9-22ad-4fbd-b26a-f18c62689451

is_signed Class

Test if type is signed integer.

Syntax

template <class Ty>
struct is_signed;

Parameters

Ty
The type to query.

Remarks

An instance of the type predicate holds true if the type Ty is a signed integral type or a cv-qualified signed integral type, otherwise it holds false.

Example

// std__type_traits__is_signed.cpp
// compile with: /EHsc
#include <type_traits>
#include <iostream>

struct trivial
    {
    int val;
    };

int main()
    {
    std::cout << "is_signed<trivial> == " << std::boolalpha
        << std::is_signed<trivial>::value << std::endl;
    std::cout << "is_signed<int> == " << std::boolalpha
        << std::is_signed<int>::value << std::endl;
    std::cout << "is_signed<unsigned int> == " << std::boolalpha
        << std::is_signed<unsigned int>::value << std::endl;
    std::cout << "is_signed<float> == " << std::boolalpha
        << std::is_signed<float>::value << std::endl;

    return (0);
    }

is_signed<trivial> == false
is_signed<int> == true
is_signed<unsigned int> == false
is_signed<float> == true

Requirements

Header: <type_traits>

Namespace: std

See also

<type_traits>
is_unsigned Class