Re: Garbage-collecting with closures

All right, suppose I pass a closure to a Tk function, as in:

$mw->Button(-text => "text", -command => sub { print "demo closure" })
+;
[download]

Will that also cause problems?

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Re: Re: Garbage-collecting with closures by mojotoad (Monsignor) on Feb 20, 2003 at 03:37 UTC
That's not a closure -- it's merely an anonymous sub reference. This would be a closure being passed to a Tk function: `sub make_counter { my $count = shift; sub { ++$count } } $mw->Button(-text => "count", -command => &make_counter(0)});` [download] That in and of itself shouldn't produce leaks -- the closure will be deconstructed along with the Button deconstruction. I would imagine you need be wary of reference cycles, however, like this (functionally meaningless): `sub make_ref_reporter { my $thing = shift; sub { ref $thing } } $mw->Button(-text => "refthing", -command => &make_ref_reporter($mw) +);` [download] Matt	[reply] [d/l] [select]

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Re: Re: Garbage-collecting with closures
by mojotoad (Monsignor) on Feb 20, 2003 at 03:37 UTC

This would be a closure being passed to a Tk function:

  sub make_counter { my $count = shift; sub { ++$count } }
  $mw->Button(-text => "count", -command => &make_counter(0)});
[download]

That in and of itself shouldn't produce leaks -- the closure will be deconstructed along with the Button deconstruction. I would imagine you need be wary of reference cycles, however, like this (functionally meaningless):

  sub make_ref_reporter { my $thing = shift; sub { ref $thing } }
  $mw->Button(-text => "refthing", -command => &make_ref_reporter($mw)
+);
[download]

Matt

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