What are the operators that can be and cannot be overloaded in C++?
List of operators that can be overloaded are:
+ - * / % ^ & | ~ !, = = ++ -- == != && || += -= /= %= ^= &= |= *= =  () -> ->* new new  delete delete 
Example 1 : Overloading ++ operator
This function is called when ++ operator operates on the object of overload class (object i in this case). In the program, void operator ++ () operator function is defined (inside overload class). This function increments the value of count by 1 for i object.
Example 2 : Overloading ++ operator and overloading postincrement operator
output: results of I = Count: 6 results of preincrement = Count: 6 Results of post increment = Count: 8 And results of i , here we see difference : Count: 9
Example 3: Overloading this [ ] operator
Example 4 : Overloading -> operator
T.num = 5 Ptr->num = 5 T->num = 5
List of operators that cannot be overloaded
1> Scope Resolution Operator (::) 2> Pointer-to-member Operator (.*) 3> Member Access or Dot operator (.) 4> Ternary or Conditional Operator (?:) 5> Object size Operator (sizeof) 6> Object type Operator (typeid)
Example 5 : Overloading this .(dot) operator
Dot (.) operator can’t be overloaded, so it cause error.
prog.cpp:8:27: error: expected type-specifier before '.' token cantover& operator.() ^ prog.cpp:8:19: error: expected ';' at end of member declaration cantover& operator.() ^ prog.cpp:8:27: error: expected unqualified-id before '.' token cantover& operator.() ^ prog.cpp: In function 'void g(X&)': prog.cpp:13:14: error: 'void X::fun()' is private void fun(); ^ prog.cpp:18:15: error: within this context x.fun(); // X::fun or cantover::fun or error? ^
This problem can be solved in several ways. At the time of standardization, it was not obvious which way would be best.
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