# $q contains the string to test
  my $quad = '([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])';
  given ($q) {
    when (    # Is it an IP?
      # matches 127 or 127. or 127.0 or 127.0. or...
      # does not match any quad above 255, or 127.0.0.1.
      #   as the fifth dot fails the match
      /^((${quad}\.){0,2}${quad}\.?|(${quad}\.){3}${quad})$/
    ) {
      $type = 'ip';
    } ## end when ( ...)
    when (/\w+\.\w+/) {    # Is it a domain name?
      # words.words
      $type = 'url'
    }
    default { $type = 'name' }    # it must be a name then...
  } ## end given