Most of the regex strings are constant, a few hundred may contain simple constructs like alternation and character classes:
(f?oo|bar|baz|etc)[\w\-]*\.[0-9]{3,})
We only extract the data if it matches. As many have suggested I benchmarked a typical case with the actual data and unless something is wrong the difference is extreme:
my %cases = (
'one_large' => sub { if($text=~/(stuff?)m0r3(?:[^:]*\.)?($big_strin
+g)/i){my $match="$1:$2"}},
'many_small' => sub { for(@strings){ if($text=~/(stuff?)m0r3(?:[^:]*
+\.)?($_)/i){my $match="$1:$2"}}},
);
print
'$text = ', length $text, " characters\n",
'$big_string = ', length $big_string, " characters\n",
'@strings = ', scalar @strings, " items\n\n";
cmpthese( 0, \%cases);
Results:
$text = 4578 characters
$big_string = 210724 characters
@strings = 10634 items
Rate many_small one_large
many_small 1.05/s -- -100%
one_large 630/s 60089% --
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