How about a recursive solution?

sub commify
{
    my($num) = @_;
    return $num if length($num)<4;
    return commify(substr($num,0,-3), $len).",".substr($num,-3,3);
}

[download]
...no super-hideous while loop there, and no regex compilation either. ;-)

The only downside is that this only works for integers.

--
hiseldl
What time is it? It's Camel Time!

In reply to Re: "Commifying" a number by hiseldl
in thread "Commifying" a number by Tanalis

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