Based on jlistf's answer: 

( undef, $areacode, $exchange, $line ) = $phn =~
    m|(1-)?\(?(\d{3})\)?-?(\d{3})-(\d{4})|;

[download]
Works on strings such as the following: 
212-555-1212
(212)555-1213 
1-(212)-555-1214
1-212-555-1215

[download]

Originally posted as a Categorized Answer.

In reply to Re: How do I break down a phone number and rebuild it? by jcwren
in thread How do I parse a telephone number? by mofo

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