+-- FIXME: docs
+data RFC733
+
+instance ConvertSuccess ZonedTime (Tagged RFC733 Ascii) where
+ {-# INLINE convertSuccess #-}
+ convertSuccess = (A.fromAsciiBuilder <$>) ∘ cs
+
+instance ConvertSuccess ZonedTime (Tagged RFC733 AsciiBuilder) where
+ {-# INLINE convertSuccess #-}
+ convertSuccess = Tagged ∘ toAsciiBuilder
+
+instance ConvertAttempt (Tagged RFC733 Ascii) ZonedTime where
+ {-# INLINE convertAttempt #-}
+ convertAttempt = parseAttempt' rfc733DateAndTime ∘ untag
+
+rfc733DateAndTime ∷ Parser ZonedTime
+rfc733DateAndTime = dateTime
+
+dateTime ∷ Parser ZonedTime
+dateTime = do weekDay ← optionMaybe $
+ do w ← longWeekDayNameP
+ <|>
+ shortWeekDayNameP
+ _ ← string ", "
+ return w
+ gregDay ← date
+ case weekDay of
+ Nothing
+ → return ()
+ Just givenWD
+ → assertWeekDayIsGood givenWD gregDay
+ (tod, timeZone) ← time
+ let lt = LocalTime gregDay tod
+ zt = ZonedTime lt timeZone
+ return zt
+
+date ∷ Parser Day
+date = do day ← read2
+ _ ← char '-' <|> char ' '
+ month ← try longMonthNameP
+ <|>
+ shortMonthNameP
+ _ ← char '-' <|> char ' '
+ year ← try read4
+ <|>
+ (+ 1900) <$> read2
+ _ ← char ' '
+ assertGregorianDateIsGood year month day
+
+time ∷ Parser (TimeOfDay, TimeZone)
+time = do tod ← hms
+ _ ← char '-' <|> char ' '
+ tz ← zone
+ return (tod, tz)
+
+hms ∷ Parser TimeOfDay
+hms = do hour ← read2
+ _ ← optional (char ':')
+ minute ← read2
+ second ← option 0 $
+ do _ ← optional (char ':')
+ read2
+ assertTimeOfDayIsGood hour minute second
+
+zone ∷ Parser TimeZone
+zone = choice [ string "GMT" *> return (TimeZone 0 False "GMT")
+ , char 'N'
+ *> choice [ string "ST" *> return (TimeZone ((-3) * 60 - 30) False "NST")
+ , return (TimeZone (1 * 60) False "N")
+ ]
+ , char 'A'
+ *> choice [ string "ST" *> return (TimeZone ((-4) * 60) False "AST")
+ , string "DT" *> return (TimeZone ((-3) * 60) False "AST")
+ , return (TimeZone ((-1) * 60) False "A")
+ ]
+ , char 'E'
+ *> choice [ string "ST" *> return (TimeZone ((-5) * 60) False "EST")
+ , string "DT" *> return (TimeZone ((-4) * 60) True "EDT")
+ ]
+ , char 'C'
+ *> choice [ string "ST" *> return (TimeZone ((-6) * 60) False "CST")
+ , string "DT" *> return (TimeZone ((-5) * 60) True "CDT")
+ ]
+ , char 'M'
+ *> choice [ string "ST" *> return (TimeZone ((-7) * 60) False "MST")
+ , string "DT" *> return (TimeZone ((-6) * 60) True "MDT")
+ , return (TimeZone ((-12) * 60) False "M")
+ ]
+ , char 'P'
+ *> choice [ string "ST" *> return (TimeZone ((-8) * 60) False "PST")
+ , string "DT" *> return (TimeZone ((-7) * 60) True "PDT")
+ ]
+ , char 'Y'
+ *> choice [ string "ST" *> return (TimeZone ((-9) * 60) False "YST")
+ , string "DT" *> return (TimeZone ((-8) * 60) True "YDT")
+ , return (TimeZone ( 12 * 60) False "Y")
+ ]
+ , char 'H'
+ *> choice [ string "ST" *> return (TimeZone ((-10) * 60) False "HST")
+ , string "DT" *> return (TimeZone (( -9) * 60) True "HDT")
+ ]
+ , char 'B'
+ *> choice [ string "ST" *> return (TimeZone ((-11) * 60) False "BST")
+ , string "DT" *> return (TimeZone ((-10) * 60) True "BDT")
+ ]
+ , char 'Z' *> return (TimeZone 0 False "Z")
+ , read4digitsTZ
+ ]
+
+toAsciiBuilder ∷ ZonedTime → AsciiBuilder
+toAsciiBuilder zonedTime