#!/usr/bin/perl
  
  use YAPE::Regex::Explain;
  print YAPE::Regex::Explain->new(qr/^\(\d{3}\) \d{3}-\d{4}$/)->explain;
  
  __END__
  
The regular expression:
  
  (?-imsx:^\(\d{3}\) \d{3}-\d{4}$)
  
matches as follows:

NODE                   EXPLANATION
====                   ===========
(?-imsx:               group, but do not capture (case-sensitive)
                       (with ^ and $ matching normally) (with . not
                       matching \n) (matching whitespace and #
                       normally):
                       
  ^                      the beginning of the string
  
  \(                     '('
  
  \d{3}                  digits (0-9) (3 times)
  
  \)                     ')'
  
                         ' '
                            
  \d{3}                  digits (0-9) (3 times)
  
  -                      '-'
  
  \d{4}                  digits (0-9) (4 times)
  
  $                      an optional \n followed by the end of the
                         string
  
)