async-await part of question is solved.

Week-5/Async-Await-Generators/solution.js

@@ -0,0 +1,48 @@
+// These are callbacks
+
+function doTask1(ms) {
+  return new Promise((resolve, reject) => {
+    setTimeout(() => {
+      resolve(`task1 done after ${ms / 1000} seconds`);
+    }, ms);
+  });
+}
+function doTask2(ms) {
+  return new Promise((resolve, reject) => {
+    setTimeout(() => {
+      resolve(`task2 done after ${ms / 1000} seconds`);
+    }, ms);
+  });
+}
+function doTask3(ms) {
+  return new Promise((resolve, reject) => {
+    setTimeout(() => {
+      reject(`rejected!! after ${ms / 1000} seconds `);
+    }, ms);
+  });
+}
+
+async function asyncDemo() {
+  // whatever value a promise resolves with is taken by variables
+  const result1 = await doTask1(2000);
+  console.log(result1);
+  const result2 = await doTask2(5000);
+  console.log(result2);
+  // if promise rejects, I am using 'try-catch' block
+
+  try {
+    const result3 = await doTask3(2000);
+    console.log(result3);
+  } catch (rejectMessage) {
+    console.log(rejectMessage);
+  }
+  // Here I used .catch()
+  const result4 = await doTask3(4000).catch((rejectMessage) =>
+    console.log(rejectMessage)
+  );
+}
+
+// async-await functionality achieved.
+asyncDemo();
+
+// Now I will try to achieve the same functionality using Generators