httpdate

# File lib/time.rb, line 343
    def httpdate(date)
      if /\A\s*
          (?:Mon|Tue|Wed|Thu|Fri|Sat|Sun),\x20
          (\d{2})\x20
          (Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec)\x20
          (\d{4})\x20
          (\d{2}):(\d{2}):(\d{2})\x20
          GMT
          \s*\z/x =~ date
        self.rfc2822(date)
      elsif /\A\s*
             (?:Monday|Tuesday|Wednesday|Thursday|Friday|Saturday|Sunday),\x20
             (\d\d)-(Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec)-(\d\d)\x20
             (\d\d):(\d\d):(\d\d)\x20
             GMT
             \s*\z/x =~ date
        year = $3.to_i
        if year < 50
          year += 2000
        else
          year += 1900
        end
        self.utc(year, $2, $1.to_i, $4.to_i, $5.to_i, $6.to_i)
      elsif /\A\s*
             (?:Mon|Tue|Wed|Thu|Fri|Sat|Sun)\x20
             (Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec)\x20
             (\d\d|\x20\d)\x20
             (\d\d):(\d\d):(\d\d)\x20
             (\d{4})
             \s*\z/x =~ date
        self.utc($6.to_i, MonthValue[$1.upcase], $2.to_i,
                 $3.to_i, $4.to_i, $5.to_i)
      else
        raise ArgumentError.new("not RFC 2616 compliant date: #{date.inspect}")
      end
    end