Your nested sub creates a closure by its comparisons with $targetElement and $targetAttribute. Each time handle_start() is run, it will use those values as they were the first time findTargetAttribute() was run, as if preserved in amber. Here is a little example of this:

$ perl -e'sub foo { my ($x,$y)=@_; sub bar {print "bar",$x,$y,$/} $x.$ +y} bar(); foo qw(baz quux); bar(); foo qw(oof zab); bar()' bar barbazquux barbazquux $

That is likely to give you "surprising" behavior at some point. Closures could be helpful with this problem, but accidental closures are rarely useful.

Here's a variation which may be more useful, binding the values from the most recent execution of foo():

$ perl -e'{ my($x,$y); sub foo { ($x,$y)=@_;$x.$y} sub bar{print "bar" +,$x,$y,$/} } bar(); foo qw(baz quux); bar(); foo qw(oof zab); bar()' bar barbazquux baroofzab $
That might actually be handy for a handler.

Such constructions are all mystical tricks, and VB'ers in maintainance are bound to screw them up.

After Compline,
Zaxo


In reply to Re: nested subroutines by Zaxo
in thread nested subroutines by marknm

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