I liked this handy little debugging aid from mjd's Perl Hardware Store talk:

  @x = (0, 'one', ' ', 3);
  $"=')(';
  print "(@x)";

[download]

And here's one that looks kind of obvious, but has a subtlety or two:

  my $i = 0;
  sub inc { ++$i }

  foreach (1..10) { print "$_\n" if(inc == 3 .. inc == 8) }

[download]

Update:

And here's one that just bit me. It took a few minutes before I realised what was going on:

my $animal = 'pig';
foreach $animal ('cat', 'dog', 'horse') {
  last if $animal eq 'dog';
}
print "$animal\n";

[download]

In reply to Re: What will this print? by grantm
in thread What will this print? by staunch

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