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is_unsigned Class

Tests if type is unsigned integer.

Syntax

template <class Ty>
struct is_unsigned;

Parameters

Ty
The type to query.

Remarks

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

Example

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

struct trivial
    {
    int val;
    };

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

    return (0);
    }
is_unsigned<trivial> == false
is_unsigned<int> == false
is_unsigned<unsigned int> == true
is_unsigned<float> == false

Requirements

Header: <type_traits>

Namespace: std

See also

<type_traits>
is_signed Class