Re: Overload operator

=?iso-8859-1?q?Erik_Wikstr=F6m?= <>
16 May 2007 06:56:18 -0700
On 16 Maj, 15:10, ek <> wrote:

In the class below I overload the "()" operator. When reading an
element in an int array "()" is therefore used. But why can't I still
use "[]" when writing something like a[2] = 4;

class MyArray {
        MyArray(int a) : data(new int[a]){}

        ~MyArray() {delete[] data;}

        int& operator()(int a){
                return data[a];

        int operator()(int a) const{
                return data[a];

        int* data;


When overloading "()" the normal "[]" operator no longer works. I can
instead do the assignment with Arr(2) = 5; but I have not specified an
overload of "()" that does assignment, why is that not needed?

This one takes care of the assignment:

        int& operator()(int a){
                return data[a];

It returns a reference to the element so when you assign to the
reference you assign to the element.

Erik Wikstr=F6m

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