1	import Base
2	import ../libs/JSON.bend as Json
3	
4	def show_result(result: Result<&1, &1, Json.Error, Json.Value>) -> String:
5	    match result:
6	        case Fail{_}:
7	            "ERROR"
8	        case Done{value}:
9	            Json.stringify(value)
10	
11	def show_batch(batch: Json.BatchResult) -> String:
12	    match batch:
13	        case Json.DocumentResult{result}:
14	            show_result(result)
15	        case Json.DocumentResults{left, right}:
16	            show_batch(left) ++ "|" ++ show_batch(right)
17	
18	def show_optional(batch: Maybe<&1, Json.BatchResult>) -> String:
19	    match batch:
20	        case None{}:
21	            "EMPTY"
22	        case Some{results}:
23	            show_batch(results)
24	
25	def check(ok: Bool) -> IO(Unit):
26	    match ok:
27	        case True{}:
28	            IO.print("GPU entry point: results and order match")
29	        case False{}:
30	            IO.die(Unit, 1, "GPU entry point returned unexpected results")
31	
32	# A native executable uses the GPU when available. --gpu off exercises the
33	# CPU fallback. JavaScript executes this example sequentially.
34	def main() -> IO(Unit):
35	    do IO<Unit>:
36	        actual : String = show_optional(Json.parse_many_gpu(
37	            "null" <> "true" <> "[1,]" <> "-12.50e+3" <>
38	            "{\"x\":[false,\"ok\"]}" <> Nil{}))
39	        check(String.eq(actual, "null|true|ERROR|-12.50e+3 |{\"x\":[false,\"ok\"]}"))