(tachyon asks about my $x if undef.)
in reply to Unusual Closure Behaviour
This was discussed extensively on p5p about a year ago.
The end result of the discussion is that this behavior is a
bug, and, although it is going to stay in
for the time being because nobody can see how to fix it,
you should not depend on it either, because it is a bug,
someone might even fix it someday.
The thread begins
and there is a recent message about it from
Jarkko Hietaniemi that
calls it a bug,
and an older message from Larry Wall that says
In Ada parlance, use of this feature would be considered erroneous.