sub skip_on_odd { next NUMBER if $_[0] % 2 }
    NUMBER: for ($i = 0; $i < 5; $i++) {
        skip_on_odd($i);
        print $i;
    }
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I would never believe that it works because the goto and the label are in different scopes but well...

from goto I can read

... It can be used to go almost anywhere else within the dynamic scope, including out of subroutines,...

So what exactly is a "dynamic scope" here? Does it mean that the label NUMBER is kind of a localized global, which is visible in called subs?

And jumping out of the sub is guarantied to clean the call stack (such avoiding any overflows)?

So please explain why a normal call works, but not the out-commented goto call (which tries to avoid the superfluous call frame)?

sub jump { goto NESTED };
 
sub cont {
  for $i (0..3) {
    for $j ("a".."c") {
      print "$i,$j\t";
      jump();           #1
      #goto &jump;      #2
    }
  NESTED:
  }
}
 
cont();
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OUTPUT1  0,a    1,a    2,a    3,a

OUTPUT2

Can't find label NESTED at /home/lanx/B/PL/PM/goto.pl line 1.
0,a    
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