steida · October 5, 2019 00:15 · Oct 5, 2019
diff --git a/setImmediate.ts b/setImmediate.ts
@@ -0,0 +1,22 @@
+// Draft uses YuzuJS/setImmediate polyfill, which can be reduced to this code.
+// But it seems request requestAnimationFrame is good enough.
+// TODO: Will it work with queue fix?
+// // https://github.com/google/closure-library/blob/master/closure/goog/async/nexttick.js#L209
+const setImmediate = (() => {
+  const channel = new MessageChannel();
+  let head: any = {};
+  let tail = head;
+  channel.port1.onmessage = () => {
+    if (head.next !== undefined) {
+      head = head.next;
+      const { callback } = head;
+      head.callback = null;
+      callback();
+    }
+  };
+  return (callback: () => void) => {
+    tail.next = { callback };
+    tail = tail.next;
+    channel.port2.postMessage(0);
+  };
+})();