In Javascript, I have used the fact that the objects are open in order to simplify logic in a 2-D grid. Instead of having the neighbors (left, right, up, and down) as attributes, I close over them in the accessors. Something like: 
for ( var i in x ) {
    for ( var j in x[i] ) {
        if ( i > 0 ) buildLeft( x[i][j], x[i][j-1] )
        else buildLeft( x[i][j], null );
    }
}

function buildLeft ( obj, target ) { obj['getLeft'] = function () { re
+turn target; }; }

[download]
And so forth. This means that I can have simplified code later on down the line.
My criteria for good software:
  1. Does it work?
  2. Can someone else come in, make a change, and be reasonably certain no bugs were introduced?

In reply to Re^6: How could we "implement" Open Classes in Perl ? by dragonchild
in thread How could we "implement" Open Classes in Perl ? by Alien

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