JavaScript: access global variables between window and opener

A nice hint (for me, the novice) at this site.

One way to access global variables between window and opener is to

centralize the location of the global variables and access them

appropriately.

Example:

doc1:

var v1 = 1, v2 = 2;

var w = window.open('doc2.htm', 'doc2');

doc2:

To access v1 and v2 global variables, you have to reach doc1's window

appropriately, and in that case, from doc2:

alert(window.opener.window.v1);