US numbers are very regular if you ignore extension numbers. The simple expression mentioned below handles all normal US cases that I just thought of while writing this.

/    ^ # Start
    (?: \D? \d{3} \D{,2} )? # Optional area code
    \d{3} \D? # Prefix with optional punctuation
    \d{4} # Last four digits
/x

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In reply to Re: Re: Character Counts by diotalevi
in thread Character Counts by Anonymous Monk

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