Operator overloading of automatic type conversions

The second method of automatic type conversion is operator overloading, which is in the form of the operator destination type (); This function converts the current type to the desired type by following the operator of the type to which you want to convert the keyword. This form of operator overloading is unique because no return value type is specified, and its return value type is the name of the overloaded operator.

1#include <iostream>2 using namespacestd;3 4 classthree{5     inti;6  Public:7Three (intIi=0): I (ii) {8 9     }Ten  One }; A  - classfour{ -     intx; the  Public: -Four (intxx): X (xx) { -          -     } +     operatorThree ()Const{//An overloaded operator that converts an object of type four into an three object.  -         returnthree (x); +     } A }; at  -  - voidg (three) { -  - } -  in intMain () { -Four Four (1); to g (four);//Call type conversion operator, operator three () const {return three (x);} +G1);//Call type conversion constructorThree (int ii=0)

 +}

In the automatic type conversion technique, the constructor technique is the destination class that performs the conversion, but using the operator technique, is the source class that performs the conversion. One drawback of the constructor technique is that it is not possible to convert from a user-defined type to a built-in type, from a user-defined type to a built-in type that only operator overloading might do.

Operator overloading of automatic type conversions