blob: 6a9bd71bb2a6c10f2f335fcd9d3df9332bd10b2e (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
|
structure FromJson :> FROMJSON = struct
fun getO (s: string) (l: Json.json): Json.json option =
case l of
Json.Obj pairs =>
(case List.find (fn tup => #1 tup = s) pairs of
NONE => NONE
| SOME tup => SOME (#2 tup))
| _ => raise Fail ("Expected JSON object, got: " ^ Json.print l)
fun get (s: string) (l: Json.json): Json.json =
(case getO s l of
NONE => raise Fail ("Failed to find JSON object key " ^ s ^ " in " ^ Json.print l)
| SOME a => a)
fun asInt (j: Json.json): int =
case j of
Json.Int i => i
| _ => raise Fail ("Expected JSON int, got: " ^ Json.print j)
fun asString (j: Json.json): string =
case j of
Json.String s => s
| _ => raise Fail ("Expected JSON string, got: " ^ Json.print j)
fun asOptionalInt (j: Json.json): int option =
case j of
Json.Null => NONE
| Json.Int i => SOME i
| _ => raise Fail ("Expected JSON int or null, got: " ^ Json.print j)
fun asOptionalString (j: Json.json): string option =
case j of
Json.Null => NONE
| Json.String s => SOME s
| _ => raise Fail ("Expected JSON string or null, got: " ^ Json.print j)
end
|
