This technique is very useful

Lookahead and lookbehind are both very useful indeed, but I think your example is better solved with a sexeger:

$amount = reverse $amount;
$amount =~ s/(\d{3})/$1,/g;
$amount = reverse $amount;

[download]

Update: oops, I guess my example doesn't commafy a floating-point number, now does it? Oh well. At least maybe someone will learn about sexegers who didn't know about them. 8^)

In reply to Re^2: Problem With Split by revdiablo
in thread Problem With Split by debiandude

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