Re: Overload Operators for referenced objects?

From:
John Harrison <john_andronicus@hotmail.com>
Newsgroups:
comp.lang.c++
Date:
Sun, 11 Feb 2007 20:08:53 GMT
Message-ID:
<pJKzh.2158$Fg4.68@newsfe5-win.ntli.net>
Jonas Huckestein wrote:

hello,

somehow i can't figure out, how to overload the [] operator for a referenced
object. if i have

class MyClass {

int operator[](int i) { return 1; };

};

...

MyClass* oskar = new MyClass();
cout << oskar[3];
delete oskar;

the compiler says "cannot convert ???OperatorSequence??? to ???int??? in
initialization". with

MyClass oskar;

it works, though. how can i use the overloaded [] for pointers? i also need
to overload arithmetic operations in my class, is there a similar problem
when dealing with referenced objects?

thanks in advance and greetings, jonas


You cannot overload operator[] for pointers, you cannot overload any
pointer operator.

It sounds like you want a class that overload several operators but
behaves like a pointer otherwise. Well, that is what you must write

class MyPtrClass
{
public:
    int operator[](int i);
    // etc...
private:
    MyClass* ptr;
};

In other words write a class that contains a single pointer to another
class, and put the overloaded operators there.

john

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