diff options
Diffstat (limited to 'lib/ur/json.ur')
-rw-r--r-- | lib/ur/json.ur | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/lib/ur/json.ur b/lib/ur/json.ur index 0865ab33..58822d4b 100644 --- a/lib/ur/json.ur +++ b/lib/ur/json.ur @@ -145,6 +145,53 @@ fun unescape s = val json_string = {ToJson = escape, FromJson = unescape} +fun rfc3339_out s = + let + val out1 = timef "%Y-%m-%dT%H:%M:%S%z" s + val len = String.length out1 + in + if len < 2 then + error <xml>timef output too short</xml> + else + String.substring out1 {Start = 0, Len = len - 2} ^ ":" + ^ String.suffix out1 (len - 2) + end + +fun rfc3339_in s = + case String.split s #"T" of + None => error <xml>Invalid RFC 3339 string "{[s]}"</xml> + | Some (date, time) => + case String.msplit {Haystack = time, Needle = "Z+-"} of + None => error <xml>Invalid RFC 3339 string "{[s]}"</xml> + | Some (time, sep, rest) => + let + val t = case readUtc (date ^ " " ^ time) of + None => error <xml>Invalid RFC 3339 string "{[s]}"</xml> + | Some t => t + + fun withOffset multiplier = + case String.split rest #":" of + None => error <xml>Invalid RFC 3339 string "{[s]}"</xml> + | Some (h, m) => + case (read h, read m) of + (Some h, Some m) => addSeconds t (multiplier * 60 * (60 * h + m)) + | _ => error <xml>Invalid RFC 3339 string "{[s]}"</xml> + in + case sep of + #"Z" => t + | #"+" => withOffset (-1) + | #"-" => withOffset 1 + | _ => error <xml>msplit returns impossible separator</xml> + end + +val json_time = {ToJson = fn tm => escape (rfc3339_out tm), + FromJson = fn s => + let + val (v, s') = unescape s + in + (rfc3339_in v, s') + end} + fun numIn [a] (_ : read a) s : a * string = let val len = String.length s |