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I'm having problems with the next code:

test1 = [0,0];
function func(test)
{
    var test2 = new Array();
    for(var i = 0; i < test.length; i++)
    if(test[i] == 0)
    {
        test[i] = 1;
        test2.push(test);
        test[i] = 0;
    }
    return test2;
}
a = func(test1);
document.write(a[0].toString()+"<br/>");
document.write(a[1].toString());

and the output is:

0,0
0,0

I have already checked with the console: when I change test[i] inside the condition, after test2.push(test), test2[test2.length] is also changed. (WHY?)

Is there a scope problem? What should I do to get an output like this?

1,0
0,1

Thanks.

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1  
a = func(test); //what is test here?? – linuxeasy Mar 7 '12 at 6:55
Upsss... corrected. It is test1. – Atoso Mar 7 '12 at 7:01

2 Answers

up vote 0 down vote

Use slice to create a copy of array:

var a = [1,2,3]
var b = a.slice();
b[0] = 0;
a[0] == 1;
share|improve this answer
up vote 2 down vote 
  test2.push(test);

This doesn't create a copy of your test array, but just stores a new reference to your input array. So all your function does, is to store a multitude of references to the same input parameter. If you want to store a real copy use this:

 test2.push( test.slice(0) );
share|improve this answer
@user1150525, both answers solved my problem. Thanks :D – Atoso Mar 7 '12 at 7:20

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