More nicely formatted version of email validator, in Perl

email validator pretty.txt

email: sub { 
      ($val = @_);
      return /
^
(
  (
    ([a-z]|\d|[!#\$%&'\*\+\-\/=\?\^_`{\|}~]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])+
    (\.([a-z]|\d|[!#\$%&'\*\+\-\/=\?\^_`{\|}~]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])+)*
  )
  |
  (
    (\x22)
    (
      (
        ((\x20|\x09)*(\x0d\x0a))?
        (\x20|\x09)+
      )?
      (
        ([\x01-\x08\x0b\x0c\x0e-\x1f\x7f]|\x21|[\x23-\x5b]|[\x5d-\x7e]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])
        |
        (\\([\x01-\x09\x0b\x0c\x0d-\x7f]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF]))
      )
    )*
    (
      ((\x20|\x09)*(\x0d\x0a))?
      (\x20|\x09)+
    )?
    (\x22)
  )
)
@
(
  (
    ([a-z]|\d|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])
    |
    (
      ([a-z]|\d|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])
      ([a-z]|\d|-|\.|_|~|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])*
      ([a-z]|\d|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])
    )
  )
  \.
)+
(
  ([a-z]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])
  |
  (
    ([a-z]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])
    ([a-z]|\d|-|\.|_|~|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])*
    ([a-z]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])
  )
)
\.?
$
/ix =~ $val;
}