ns_if_addref( T* expr )
ns_if_addref( T expr )
ns_if_addref( T* expr )    // Making this a |inline| |template| allows |expr| to be evaluated only once,    //  yet still denies you the ability to |AddRef()| an |nsCOMPtr|.    // Note that |NS_ADDREF()| already has this property in the non-logging case.  {    return expr ? expr->AddRef() : 0;  }