You could also use unpack.

$ perl -E '
say for map { join q{-}, unpack q{(a3)*}, $_ }
   qw{ 12 123 1234 12345 123456 1234567 };'
12
123
123-4
123-45
123-456
123-456-7
$

[download]

I hope this is helpful.

Cheers,

JohnGG

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

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