Are we still avoiding spoilers? I'll just play it safe.

wouldn't it immediately change again as soon as the callback exits, anyway, as the foreach goes into its next iteration?

It would, but it would also clobber the original entry from @callbacks. Here's a demonstration:

my @callbacks = (
  sub { print "one\n" },
  sub { print "two\n"; $_ = "three"; }
);

print "@callbacks\n";
for (@callbacks) { $_->() }
print "@callbacks\n";

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In reply to Re: Re: Action at a great distance by revdiablo
in thread Action at a great distance by sfink

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