+
+iso8601DateFormat :: Maybe String -> String
+iso8601DateFormat timeFmt =
+ "%Y-%m-%d" ++ case timeFmt of
+ Nothing -> "" -- normally, ISO-8601 just defines YYYY-MM-DD
+ Just fmt -> ' ' : fmt -- but we can add a time spec
+
+
+rfc822DateFormat :: String
+rfc822DateFormat = "%a, %_d %b %Y %H:%M:%S %Z"