operator== (<memory>)

Tests for equality between objects.

template<class Type, class Other>
   bool operator==(
      const allocator<Type>& _Left,
      const allocator<Other>& _Right
   ) throw();
template<class Ty1, class Del1, class Ty2, class Del2>
    bool operator==(
        const unique_ptr<Ty1, Del1>& _Left,
        const unique_ptr<Ty2, Del2>& _Right
    );
template<class Ty1, class Ty2>
    bool operator==(
      const shared_ptr<Ty1>& _Left;,
      const shared_ptr<Ty2>& _Right
   );

Parameters

• _Left
  One of the objects to be tested for equality.

• _Right
  One of the objects to be tested for equality.

• Ty1
  The type controlled by the left shared pointer.

• Ty2
  The type controlled by the right shared pointer.

Return Value

true if the objects are equal, false if objects are not equal.

Remarks

The first template operator returns true. (All default allocators are equal.)

The second and third template operators return _Left.get() == _Right.get().

Example

// memory_op_eq.cpp
// compile with: /EHsc
#include <memory>
#include <iostream>
#include <vector>

using namespace std;

int main( ) 
{
   allocator<char> Alloc;
   vector <int>:: allocator_type v1Alloc;

   allocator<char> cAlloc(Alloc); 
   allocator<int> cv1Alloc(v1Alloc);

   if ( cv1Alloc == v1Alloc )
      cout << "The allocator objects cv1Alloc & v1Alloc are equal."
           << endl;
   else
      cout << "The allocator objects cv1Alloc & v1Alloc are not equal."
           << endl;

   if ( cAlloc == Alloc )
      cout << "The allocator objects cAlloc & Alloc are equal."
           << endl;
   else
      cout << "The allocator objects cAlloc & Alloc are not equal."
           << endl;
}

The allocator objects cv1Alloc & v1Alloc are equal.
The allocator objects cAlloc & Alloc are equal.

 

// std_tr1__memory__operator_eq.cpp 
// compile with: /EHsc 
#include <memory> 
#include <iostream> 
 
int main() 
    { 
    std::shared_ptr<int> sp0(new int(0)); 
    std::shared_ptr<int> sp1(new int(0)); 
 
    std::cout << "sp0 == sp0 == " << std::boolalpha 
        << (sp0 == sp0) << std::endl; 
    std::cout << "sp0 == sp1 == " << std::boolalpha 
        << (sp0 == sp1) << std::endl; 
 
    return (0); 
    } 
 

sp0 == sp0 == true
sp0 == sp1 == false

Requirements

Header: <memory>

Namespace: std

See Also

Reference

auto_ptr Class

shared_ptr Class

unique_ptr Class

Other Resources

auto_ptr Members

shared_ptr::operator==

unique_ptr Members

Change History

Date	History	Reason
August 2010	Added TR1 extensions information.	Information enhancement.