See also Params::Validate, FormValidator::Simple, other validators

Regexp::English

use Regexp::English;
print Regexp::English ->new
    ->beginning_of_string
    ->literal('SR')
    ->digit
    ->digit
    ->digit
    ->digit
    ->digit
    ->digit
    ->digit
    ->end_of_string, "\n";
__END__
(?^:\ASR\d\d\d\d\d\d\d\Z)
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YAPE::Regex::Explain

use YAPE::Regex::Explain;
print YAPE::Regex::Explain->new(
qr{(?:\ASR\d\d\d\d\d\d\d\Z)}
)->explain;
__END__
The regular expression:

(?-imsx:(?:\ASR\d\d\d\d\d\d\d\Z))

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):
----------------------------------------------------------------------
  (?:                      group, but do not capture:
----------------------------------------------------------------------
    \A                       the beginning of the string
----------------------------------------------------------------------
    SR                       'SR'
----------------------------------------------------------------------
    \d                       digits (0-9)
----------------------------------------------------------------------
    \d                       digits (0-9)
----------------------------------------------------------------------
    \d                       digits (0-9)
----------------------------------------------------------------------
    \d                       digits (0-9)
----------------------------------------------------------------------
    \d                       digits (0-9)
----------------------------------------------------------------------
    \d                       digits (0-9)
----------------------------------------------------------------------
    \d                       digits (0-9)
----------------------------------------------------------------------
    \Z                       before an optional \n, and the end of
                             the string
----------------------------------------------------------------------
  )                        end of grouping
----------------------------------------------------------------------
)                        end of grouping
----------------------------------------------------------------------
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