1 files changed, 66 insertions, 0 deletions
diff --git a/viz.js/promise/promise.ml b/viz.js/promise/promise.ml
new file mode 100755
index 0000000..f9f7e53
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+++ b/viz.js/promise/promise.ml
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+open Js_of_ocaml
+
+type ('a, 'b) promise
+
+type 'a resolve = 'a -> unit
+
+type 'a reject = 'a -> unit
+
+let promise_global = Js.Unsafe.global##._Promise
+
+let is_supported () = Js.Optdef.test promise_global
+
+let make f =
+  Js.Unsafe.new_obj promise_global [|Js.Unsafe.inject f|]
+
+let resolve value =
+  Js.Unsafe.fun_call promise_global##.resolve [|Js.Unsafe.inject value|]
+
+let reject value =
+  Js.Unsafe.fun_call promise_global##.reject [|Js.Unsafe.inject value|]
+
+let js_of_opt = function
+  | Some value -> Js.Unsafe.inject value
+  | None       -> Js.Unsafe.inject Js.undefined
+
+let then_bind ~on_fulfilled ?on_rejected promise =
+  Js.Unsafe.meth_call promise "then"
+    [|Js.Unsafe.inject on_fulfilled; js_of_opt on_rejected|]
+
+let then_map ~on_fulfilled ?on_rejected promise =
+  Js.Unsafe.meth_call promise "then"
+    [|Js.Unsafe.inject on_fulfilled; js_of_opt on_rejected|]
+
+let catch_bind ~on_rejected promise =
+  Js.Unsafe.meth_call promise "catch" [|Js.Unsafe.inject on_rejected|]
+
+let catch_map ~on_rejected promise =
+  Js.Unsafe.meth_call promise "catch" [|Js.Unsafe.inject on_rejected|]
+
+let then_final ~on_fulfilled ~on_rejected promise =
+  Js.Unsafe.meth_call promise "then"
+    [|Js.Unsafe.inject on_fulfilled; Js.Unsafe.inject on_rejected|]
+
+let all promises =
+  let intermediate_promise =
+    Js.Unsafe.fun_call promise_global##.all
+      [|Js.Unsafe.inject (Js.array promises)|]
+  in
+  then_map
+    ~on_fulfilled:(fun js_array -> Js.to_array js_array) intermediate_promise
+
+let race promises =
+  Js.Unsafe.fun_call promise_global##.race
+    [|Js.Unsafe.inject (Js.array promises)|]
+
+module Infix = struct
+  let (>>=) promise on_fulfilled = then_bind ~on_fulfilled promise
+  let (>|=) promise on_fulfilled = then_map  ~on_fulfilled promise
+
+  let (>>~) promise on_rejected = catch_bind ~on_rejected promise
+  let (>|~) promise on_rejected = catch_map  ~on_rejected promise
+
+  let (>||) promise (on_fulfilled, on_rejected) =
+    then_final ~on_fulfilled ~on_rejected promise
+end
+