Re: 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--;
  }
}
[download]

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});}

Comment on Re: fall through switch/case in perl Download Code

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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.	[reply]
Re^3: fall through switch/case in perl by radiantmatrix (Parson) on Sep 07, 2004 at 15:40 UTC
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]
Re^4: fall through switch/case in perl by Anonymous Monk on Sep 07, 2004 at 15:59 UTC
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.	[reply]
Re^5: fall through switch/case in perl by radiantmatrix (Parson) on Sep 07, 2004 at 18:21 UTC
Re^6: fall through switch/case in perl by demerphq (Chancellor) on Sep 14, 2004 at 12:09 UTC
Re^6: fall through switch/case in perl by Anonymous Monk on Sep 07, 2004 at 23:11 UTC
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