Test nested callbacks, patterns, evaluation count, and exceptions

test.ml

@@ -0,0 +1,22 @@
+let each xs callback = List.map callback xs
+
+let () =
+  assert ((let%continue x = each [1; 2; 3] in x * 5) = [5; 10; 15]);
+  assert ((let%cps x = each [1; 2] in x + 1) = [2; 3]);
+  assert ((let%continue (x, y) = each [2, 3] in x + y) = [5]);
+  assert ((let%continue x = each [1; 2] in
+           let%continue y = each [3; 4] in x + y) = [[4; 5]; [5; 6]]);
+  let active = ref false in
+  let scope callback = active := true; callback (); active := false in
+  (let%continue () = scope in assert !active);
+  assert (not !active);
+  let calls = ref 0 in
+  let producer () = incr calls; each [1; 2] in
+  assert ((let%continue x = producer () in x) = [1; 2]);
+  assert (!calls = 1);
+  assert ((let%continue _ = each [] in failwith "unreachable") = []);
+  assert ((let%continue x = (let%continue f = each [each [7]] in f) |> List.hd
+           in x + 1) = [8]);
+  (try (let%continue () = scope in failwith "callback"); assert false
+   with Failure message -> assert (message = "callback"));
+  print_endline "continuum_ppx: behavior checks passed"