1 -- |This module provides functions to parse and format RFC 733 date
4 -- The syntax is as follows:
6 -- > date-time ::= [ day-of-week ", " ] date SP time ("-" | SP) zone
7 -- > day-of-week ::= "Monday" | "Mon" | "Tuesday" | "Tue"
8 -- > | "Wednesday" | "Wed" | "Thursday" | "Thu"
9 -- > | "Friday" | "Fri" | "Saturday" | "Sat"
10 -- > | "Sunday" | "Sun"
11 -- > date ::= day ("-" | SP) month ("-" | SP) year
13 -- > year ::= 2DIGIT | 4DIGIT
14 -- > month ::= "January" | "Jan" | "February" | "Feb"
15 -- > | "March" | "Mar" | "April" | "Apr"
16 -- > | "May" | "June" | "Jun"
17 -- > | "July" | "Jul" | "August" | "Aug"
18 -- > | "September" | "Sep" | "October" | "Oct"
19 -- > | "November" | "Nov" | "December" | "Dec"
20 -- > time ::= hour [ ":" ] minute [ [ ":" ] second ]
22 -- > minute ::= 2DIGIT
23 -- > second ::= 2DIGIT
24 -- > zone ::= "GMT" ; Universal Time
25 -- > | "NST" ; Newfoundland: -3:30
26 -- > | "AST" | "ADT" ; Atlantic : -4 / -3
27 -- > | "EST" | "EDT" ; Eastern : -5 / -4
28 -- > | "CST" | "CDT" ; Central : -6 / -5
29 -- > | "MST" | "MDT" ; Mountain : -7 / -6
30 -- > | "PST" | "PDT" ; Pacific : -8 / -7
31 -- > | "YST" | "YDT" ; Yukon : -9 / -8
32 -- > | "HST" | "HDT" ; Haw/Ala : -10 / -9
33 -- > | "BST" | "BDT" ; Bering : -11 / -10
39 -- > | ("+" | "-") 4DIGIT ; Local diff: HHMM
40 module Data.Time.RFC733
46 import qualified Text.Parsec as P
49 import Data.Time.Calendar.WeekDate
50 import Data.Time.HTTP.Common
51 import Data.Time.RFC733.Parsec
53 -- |Format a 'ZonedTime' in RFC 733.
54 format :: ZonedTime -> String
56 = let localTime = zonedTimeToLocalTime zonedTime
57 timeZone = zonedTimeZone zonedTime
58 (year, month, day) = toGregorian (localDay localTime)
59 (_, _, week) = toWeekDate (localDay localTime)
60 timeOfDay = localTimeOfDay localTime
62 concat [ longWeekDayName week
66 , shortMonthName month
70 , show2 (todHour timeOfDay)
72 , show2 (todMin timeOfDay)
74 , show2 (floor (todSec timeOfDay))
76 , show4digitsTZ timeZone
79 -- |Parse an RFC 733 date and time string. When the string can't be
80 -- parsed, it returns 'Nothing'.
81 parse :: String -> Maybe ZonedTime
82 parse src = case P.parse p "" src of
86 p = do zt <- rfc733DateAndTime