This exact problem is actually covered in the panther book as an eval() example. The code is basically like yours, but the if() statement is built with a join() command: 
@patterns = qw(cat dog);
$code = 'if (/';
$code .= join('/ && /', @patterns);
$code .= '/) {
   print "Found a DOG and a CAT!\n\n";
}';
eval $code;
die "Error: $@" if ($@);

[download]
Here's another solution which probably has no practical application, but looks cool anyway: 
#!/usr/bin/perl

use strict;

my (@str, @search, %words, @matched_words);

# Token string
@str = qw(cat dog rat elephant giraffe);

# List of search keys to check for
@search = qw(cat dog);

# Create a hash keyed with the token list.
# E.g. $words{elephant} = 1; $words{rat} = 1; etc
@words{@str} = (1) x @str;

# Create an array with the same number of elements
# as the number of search keys that were present in
# the original string.
@matched_words = @words{@search};

# Check to see if the number of matched words
# is equal to the number of words we were searching
# for
if (scalar @search == scalar @matched_words)
{
        print "Found a DOG and a CAT!\n\n";
}

[download]
It's case-sensitive and doesn't do regular expressions, but I imagine it's pretty fast.

-Matt

In reply to Re: How to generate Perl statements on the fly and execute them when they are synthesized. by DrManhattan
in thread How to generate Perl statements on the fly and execute them when they are synthesized. by kleinbiker7

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