In any sort of production code, i would go so far as to recommend a clearer if slower classic C-style for loop. Yes, it's not optimized, but it is maintainable by someone who isn't a perl expert:

my $result = '';
for(my $i = 0; $i < $n; $i++) {
    $result .= "$i cat\n\man\n";
}

[download]

Or a slightly different variant that would lead itself to easier debugging:

my @lines;
for(my $i = 0; $i < $n; $i++) {
    push @lines, "$i cat";
    push @lines, "man";
}
#print Dumper(\@lines);
my $result = join("\n", @lines);

[download]

Unless it's really timing critical code (in which case thinking about doing the stuff in XS/Inline::C is also an option), long term maintainability and readability is (almost) always more important than saving a couple percent CPU cycles.

So the answer, at least from my point of view: Can you do it faster with a regular expression: Maybe. Can you do it better? Not a chance, unless you add a few long paragraphs of explanations in the code comments that clearly lays out how to chance/update the code in a few years to fit the changing requirements of the project.

PerlMonks XP is useless? Not anymore: XPD - Do more with your PerlMonks XP

In reply to Re^3: Can I get some help with a regex please by cavac
in thread Can I get some help with a regex please by misterperl

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