AsyncArray implementation using setImmediate

tshemsedinov · tshemsedinov · commit b2a89ac2897e · 2020-08-22T22:10:22.000+03:00
diff --git a/JavaScript/a-immediate.js b/JavaScript/a-immediate.js
@@ -0,0 +1,31 @@
+'use strict';
+
+class AsyncArray extends Array {
+  [Symbol.asyncIterator]() {
+    let i = 0;
+    return {
+      next: () => new Promise(resolve => {
+        setImmediate(() => resolve({
+          value: this[i],
+          done: i++ === this.length
+        }));
+      })
+    };
+  }
+}
+
+// Usage
+
+let k = 0;
+
+const timer = setInterval(() => k++, 10);
+
+(async () => {
+  const numbers = new AsyncArray(10000).fill(1);
+  let i = 0;
+  for await (const number of numbers) {
+    if (number) i++;
+  }
+  clearInterval(timer);
+  console.dir({ i, k });
+})();
