X-Git-Url: http://git.cielonegro.org/gitweb.cgi?p=time-http.git;a=blobdiff_plain;f=Data%2FTime%2FRFC822.hs;h=152d99290f57e89915e72eaf80efd36e72c22e1e;hp=72e3b28f2634b2ce39416b35d3b70b19244b4cd3;hb=d82d61b;hpb=746e89579242035ff05ceec12dd151b4b9931a5f

diff --git a/Data/Time/RFC822.hs b/Data/Time/RFC822.hs
index 72e3b28..152d992 100644
--- a/Data/Time/RFC822.hs
+++ b/Data/Time/RFC822.hs
@@ -1,4 +1,61 @@
+{-# LANGUAGE
+    UnicodeSyntax
+  #-}
+-- |This module provides functions to parse and format RFC 822 date
+-- and time formats.
+--
+-- The syntax is as follows:
+--
+-- > date-time   ::= [ day-of-week ", " ] date SP time SP zone
+-- > day-of-week ::= "Mon" | "Tue" | "Wed" | "Thu"
+-- >               | "Fri" | "Sat" | "Sun"
+-- > date        ::= day SP month SP year
+-- > day         ::= 2DIGIT
+-- > year        ::= 2DIGIT             ; Yes, only 2 digits.
+-- > month       ::= "Jan" | "Feb" | "Mar" | "Apr"
+-- >               | "May" | "Jun" | "Jul" | "Aug"
+-- >               | "Sep" | "Oct" | "Nov" | "Dec"
+-- > time        ::= hour ":" minute [ ":" second ]
+-- > hour        ::= 2DIGIT
+-- > minute      ::= 2DIGIT
+-- > second      ::= 2DIGIT
+-- > zone        ::= "UT"  | "GMT"      ; Universal Time
+-- >               | "EST" | "EDT"      ; Eastern : -5 / -4
+-- >               | "CST" | "CDT"      ; Central : -6 / -5
+-- >               | "MST" | "MDT"      ; Mountain: -7 / -6
+-- >               | "PST" | "PDT"      ; Pacific : -8 / -7
+-- >               | "Z"                ; UT
+-- >               | "A"                ;  -1
+-- >               | "M"                ; -12
+-- >               | "N"                ;  +1
+-- >               | "Y"                ; +12
+-- >               | ("+" | "-") 4DIGIT ; Local diff: HHMM
 module Data.Time.RFC822
-    (
+    ( -- * Formatting
+      toAscii
+    , toAsciiBuilder
+
+      -- * Parsing
+    , fromAscii
+    , rfc822DateAndTime
     )
     where
+import Data.Ascii (Ascii)
+import qualified Data.Ascii as A
+import qualified Data.Attoparsec.Char8 as P
+import Data.Time
+import Data.Time.RFC822.Internal
+import Prelude.Unicode
+
+-- |Convert a 'ZonedTime' to RFC 822 date and time string.
+toAscii ∷ ZonedTime → Ascii
+toAscii = A.fromAsciiBuilder ∘ toAsciiBuilder
+
+-- |Parse an RFC 822 date and time string. When the string can't be
+-- parsed, it returns @'Left' err@.
+fromAscii ∷ Ascii → Either String ZonedTime
+fromAscii = P.parseOnly p ∘ A.toByteString
+    where
+      p = do zt ← rfc822DateAndTime
+             P.endOfInput
+             return zt