This doesn't answer your question, but i'd rather use a dispatch table (a lookup hash) instead of Switch ... but i rarely care about premature optimization. In your case, you are also checking regexes, so i would probably use Tie::Hash::Regex like so: 
use strict;
use warnings;
use Tie::Hash::Regex;

tie my %hash, 'Tie::Hash::Regex';

%hash = (
   'foo.txt'  => 1,
   'bar.html' => 2,
   '..'       => undef,
   '.'        => undef,
   DEFAULT    => undef,
);

my $arg = shift || 'DEFAULT';
my $candidate = $hash{$arg};

die "invalid arg\n" unless $candidate;
print "$candidate\n";

[download]
Since most of my work is Web based, i care more about maintainability and readability than efficiency .. but i do care about efficiency when it really matters.

UPDATE:
I forgot to mention CGI::Application which uses a dispatch table to control which runmode your CGI is in. If you haven't seen it yet, you really should RTFM on CGI::App ...

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

In reply to Re: What is the most efficient perl switch/case statement? by jeffa
in thread What is the most efficient perl switch/case statement? by synistar

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