in reply to fall through switch/case in perl

Your example problem is fairly simple, but for more complicated switch-like behavior, 
my @switch_foo = ("a","b","c",...);
for ($var) {
  my $junk = shift;
  while ($junk > 0) {
    print $switch_foo[$junk]);
    $junk--;
  }
}

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It's way overkill for your particular problem, but for commplicated situations, @switch_foo can contain references to subs, making it quite powerful (if a little slow).

In practice, however, if your algorithm needs a switch equivalent, you're better off re-thinking your algorithm.

Update: fixed the code so that it works!

--
$me = rand($hacker{perl});

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Re^2: fall through switch/case in perl
by Anonymous Monk on Sep 07, 2004 at 15:23 UTC
    Your code will either not print anything, or it'll never finish printing.

    In practice, however, if your algorithm needs a switch equivalent, you're better off re-thinking your algorithm.

    Eh? And why is that? That's a pretty bold statement, considering many languages do have a 'switch', perl6 will have a switch, there's Switch.pm, both the manual and the FAQ discuss it (without dismissing it as choicing a bad algorithm), and it has been on the wishlist since the very first release of Perl in 1987.

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      Your code will either not print anything, or it'll never finish printing.

      You're right, I forgot the $junk--; after the print statement.

      That's a pretty bold statement, considering many languages do have a 'switch', perl6 will have a switch, there's Switch.pm, both the manual and the FAQ discuss it (without dismissing it as choicing a bad algorithm), and it has been on the wishlist since the very first release of Perl in 1987.

      I never said switch was bad code. Perl6 will have a switch because a lot of people want it, and it is very readable. However, switch statements are unbelievably over-used. I stand by my statement; chances are, if your algorithm needs switch, you can come up with a better algorithm. There are, of course, a few exceptions.

      As to your "considering many languages have a 'switch'", multiplicity does not correctness make.

      --
      $me = rand($hacker{perl});
[reply]
        I never said switch was bad code.

        You mean, people should rethink good code?

        As to your "considering many languages have a 'switch'", multiplicity does not correctness make.

        No, but it does mean your bold statement needs at least a shred of backup. Just stating "switch statements are unbelievably over-used" does not make correctness either. Back up your claim.

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