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is_scalar Class

 

The latest version of this topic can be found at is_scalar Class.

Tests if type is scalar.

Syntax

template <class Ty>  
struct is_scalar;  

Parameters

Ty
The type to query.

Remarks

An instance of the type predicate holds true if the type Ty is an integral type, a floating point type, an enumeration type, a pointer type, or a pointer to member type, or a cv-qualified form of one of them, otherwise it holds false.

Example

// std_tr1__type_traits__is_scalar.cpp   
// compile with: /EHsc   
#include <type_traits>   
#include <iostream>   
  
struct trivial   
    {   
    int val;   
    };   
  
int main()   
    {   
    std::cout << "is_scalar<trivial> == " << std::boolalpha   
        << std::is_scalar<trivial>::value << std::endl;   
    std::cout << "is_scalar<trivial *> == " << std::boolalpha   
        << std::is_scalar<trivial *>::value << std::endl;   
    std::cout << "is_scalar<int> == " << std::boolalpha   
        << std::is_scalar<int>::value << std::endl;   
    std::cout << "is_scalar<float> == " << std::boolalpha   
        << std::is_scalar<float>::value << std::endl;   
  
    return (0);   
    }  
  
is_scalar<trivial> == false  
is_scalar<trivial *> == true  
is_scalar<int> == true  
is_scalar<float> == true  

Requirements

Header: <type_traits>

Namespace: std

See Also

<type_traits>
is_compound Class