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is_unsigned Class

 

The latest version of this topic can be found at 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_tr1__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