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is_pointer Class

 

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

Tests if type is a pointer.

Syntax

template <class Ty>  
struct is_pointer;  

Parameters

Ty
The type to query.

Remarks

An instance of the type predicate holds true if the type Ty is a pointer to void, a pointer to an object, or a pointer to a function, or a cv-qualified form of one of them, otherwise it holds false. Note that is_pointer holds false if Ty is a pointer to member or a pointer to member function.

Example

// std_tr1__type_traits__is_pointer.cpp   
// compile with: /EHsc   
#include <type_traits>   
#include <iostream>   
  
struct trivial   
    {   
    int val;   
    };   
  
int main()   
    {   
    std::cout << "is_pointer<trivial> == " << std::boolalpha   
        << std::is_pointer<trivial>::value << std::endl;   
    std::cout << "is_pointer<int trivial::*> == " << std::boolalpha   
        << std::is_pointer<int trivial::*>::value << std::endl;   
    std::cout << "is_pointer<trivial *> == " << std::boolalpha   
        << std::is_pointer<trivial *>::value << std::endl;   
    std::cout << "is_pointer<int> == " << std::boolalpha   
        << std::is_pointer<int>::value << std::endl;   
    std::cout << "is_pointer<int *> == " << std::boolalpha   
        << std::is_pointer<int *>::value << std::endl;   
  
    return (0);   
    }  
  
is_pointer<trivial> == false  
is_pointer<int trivial::*> == false  
is_pointer<trivial *> == true  
is_pointer<int> == false  
is_pointer<int *> == true  

Requirements

Header: <type_traits>

Namespace: std

See Also

<type_traits>
is_member_pointer Class
is_reference Class