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title: "Relational Function Templates | Microsoft Docs"
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---
# Relational Function Templates
**Microsoft Specific**  
  
## Syntax  
  
```  
  
      template<typename _InterfaceType> bool operator==(  
   int NULL,  
   _com_ptr_t<_InterfaceType>& p   
);  
template<typename _Interface,  
   typename _InterfacePtr> bool operator==(  
   _Interface* i,  
   _com_ptr_t<_InterfacePtr>& p   
);  
template<typename _Interface> bool operator!=(  
   int NULL,  
   _com_ptr_t<_Interface>& p   
);  
template<typename _Interface,  
   typename _InterfacePtr> bool operator!=(  
   _Interface* i,  
   _com_ptr_t<_InterfacePtr>& p   
);  
template<typename _Interface> bool operator<(  
   int NULL,  
   _com_ptr_t<_Interface>& p   
);  
template<typename _Interface,  
   typename _InterfacePtr> bool operator<(  
   _Interface* i,  
   _com_ptr_t<_InterfacePtr>& p   
);  
template<typename _Interface> bool operator>(  
   int NULL,  
   _com_ptr_t<_Interface>& p   
);  
template<typename _Interface,  
   typename _InterfacePtr> bool operator>(  
   _Interface* i,  
   _com_ptr_t<_InterfacePtr>& p   
);  
template<typename _Interface> bool operator<=(  
   int NULL,  
   _com_ptr_t<_Interface>& p   
);  
template<typename _Interface,  
   typename _InterfacePtr> bool operator<=(  
   _Interface* i,  
   _com_ptr_t<_InterfacePtr>& p   
);  
template<typename _Interface> bool operator>=(  
   int NULL,  
   _com_ptr_t<_Interface>& p   
);  
template<typename _Interface,  
   typename _InterfacePtr> bool operator>=(  
   _Interface* i,  
   _com_ptr_t<_InterfacePtr>& p   
);  
```  
  
#### Parameters  
 *i*  
 A raw interface pointer.  
  
 `p`  
 A smart pointer.  
  
## Remarks  
 These function templates allow comparison with a smart pointer on the right side of the comparison operator. These are not member functions of `_com_ptr_t`.  
  
 **END Microsoft Specific**  
  
## See Also  
 [_com_ptr_t Class](../cpp/com-ptr-t-class.md)