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is_integral Class

Tests if type is integral.

template<class Ty>
    struct is_integral;

Parameters

  • Ty
    The type to query.

Remarks

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

An integral type is one of bool, char, unsigned char, signed char, wchar_t, short, unsigned short, int, unsigned int, long, and unsigned long. In addition, with compilers that provide them, an integral type can be one of long long, unsigned long long, __int64, and unsigned __int64.

Example

 

// std_tr1__type_traits__is_integral.cpp 
// compile with: /EHsc 
#include <type_traits> 
#include <iostream> 
 
struct trivial 
    { 
    int val; 
    }; 
 
int main() 
    { 
    std::cout << "is_integral<trivial> == " << std::boolalpha 
        << std::is_integral<trivial>::value << std::endl; 
    std::cout << "is_integral<int> == " << std::boolalpha 
        << std::is_integral<int>::value << std::endl; 
    std::cout << "is_integral<float> == " << std::boolalpha 
        << std::is_integral<float>::value << std::endl; 
 
    return (0); 
    } 
 
is_integral<trivial> == false
is_integral<int> == true
is_integral<float> == false

Requirements

Header: <type_traits>

Namespace: std

See Also

Reference

<type_traits>

is_enum Class

is_floating_point Class