1 {-# LANGUAGE FlexibleContexts #-}
2 {-# OPTIONS_HADDOCK prune #-}
4 module Data.Time.RFC822.Parsec
15 import Data.Time.Calendar.WeekDate
16 import Data.Time.HTTP.Common
19 -- |This is a parsec parser for RFC 822 date and time strings.
20 rfc822DateAndTime :: Stream s m Char => ParsecT s u m ZonedTime
21 rfc822DateAndTime = dateTime
23 dateTime :: Stream s m Char => ParsecT s u m ZonedTime
24 dateTime = do weekDay <- optionMaybe $
25 do w <- shortWeekDayNameP
31 -> return () -- No day in week exists.
33 -> assertWeekDayIsGood givenWD gregDay
34 (tod, timeZone) <- rfc822time
35 let lt = LocalTime gregDay tod
36 zt = ZonedTime lt timeZone
39 date :: Stream s m Char => ParsecT s u m Day
40 date = do day <- read2
42 month <- shortMonthNameP
44 year <- liftM (+ 1900) read2
46 assertGregorianDateIsGood year month day
48 rfc822time :: Stream s m Char => ParsecT s u m (TimeOfDay, TimeZone)
49 rfc822time = do tod <- hour
54 hour :: Stream s m Char => ParsecT s u m TimeOfDay
55 hour = do hour <- read2
56 minute <- char ':' >> read2
57 second <- option 0 (char ':' >> read2)
58 assertTimeOfDayIsGood hour minute second
60 zone :: Stream s m Char => ParsecT s u m TimeZone
61 zone = choice [ string "UT" >> return (TimeZone 0 False "UT" )
62 , string "GMT" >> return (TimeZone 0 False "GMT")
64 >> choice [ string "ST" >> return (TimeZone ((-5) * 60) False "EST")
65 , string "DT" >> return (TimeZone ((-4) * 60) True "EDT")
68 >> choice [ string "ST" >> return (TimeZone ((-6) * 60) False "CST")
69 , string "DT" >> return (TimeZone ((-5) * 60) True "CDT")
72 >> choice [ string "ST" >> return (TimeZone ((-7) * 60) False "MST")
73 , string "DT" >> return (TimeZone ((-6) * 60) True "MDT")
74 , return (TimeZone ((-12) * 60) False "M")
77 >> choice [ string "ST" >> return (TimeZone ((-8) * 60) False "PST")
78 , string "DT" >> return (TimeZone ((-7) * 60) True "PDT")
80 , char 'Z' >> return (TimeZone 0 False "Z")
81 , char 'A' >> return (TimeZone ((-1) * 60) False "A")
82 , char 'N' >> return (TimeZone ( 1 * 60) False "N")
83 , char 'Y' >> return (TimeZone ( 12 * 60) False "Y")