$string =~ s/(\w\w\w)/$1-/g;

[download]

UPDATE: As Ken pointed out correctly, this solution is wrong as it puts an additional - in a case like '123456'.

So, putting a negative lookahead to the pattern should do the trick:

$string =~ s/(\w\w\w)(?!$)/$1-/g;

[download]

McA

In reply to Re: Regex split string into n-length by McA
in thread Regex split string into n-length by hankcoder

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