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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__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