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Every now and then I try to think of ideas for Obfuscated code. I seldom follow through, but it is often a great learning exercise. Consider the following code:
#!/usr/bin/perl use strict; use warnings; sub jump { my $place = 'START'; goto $place; } START: print "Hello, world\n"; jump();
As you might expect, this creates an infinite loop. I wondered what might happen if $place were a tied variable that instead of fetching a value - did a goto elsewhere. Would the original goto ever get called?
#!/usr/bin/perl use strict; use warnings; sub jump { tie my $place, 'main'; goto $place; } START: print "Hello, world\n"; jump(); print "I am jumping over this spot\n"; END: print "Goodbye, cruel world\n"; sub TIESCALAR { bless {}, $_[0] } sub STORE { print "Read only\n"; } sub FETCH { goto END; }
This dies yelling about Can't find label END at ... First, I know that Perl supports goto label out of a sub as demonstrated by the first snippet. Second, I can't find anything in goto docs that would suggest this shouldn't work. Can anyone shed some light?

Cheers - L~R

In reply to Mixing tied variables with goto label by Limbic~Region

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