I'd work backwards. The last step is obviously a join on "<br>". The step before that would be the insertion of dashes. The step before that would be splitting into fifteen-digit blocks. Hence:

$s = join '<br>', map { /(\d{5})(\d{5})(.*)/ && "$1-$2-$3" } ($s =~ /\d{15}/g);

    -- Chip Salzenberg, Free-Floating Agent of Chaos

In reply to Re: A regex question... by chip
in thread A regex question... by thezip

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