Merge pull request #2 from shotlom/master

Promises

Author: yamalight

index.js

@@ -9,49 +9,44 @@ const NS_PER_SEC = 1e9;
 const workerPath = path.resolve('factorial-worker.js');
 
 const calculateFactorialWithWorker = number => {
+  // Insert the array preparation code.
   if (number === 0) {
     return 1;
   }
-  return new Promise(async (parentResolve, parentReject) => {
-    const numbers = []; 
-    for (let i = 1n; i <= number; i++) {
-      numbers.push(i);
-    }
+  const numbers = [];
 
-    const segmentSize = Math.ceil(numbers.length / userCPUCount);
-    const segments = [];
+  for (let i = 1n; i <= number; i++) {
+    numbers.push(i);
+  }
 
-    console.log(numbers.length, userCPUCount, segmentSize);
+  const segmentSize = Math.ceil(numbers.length / userCPUCount);
+  const segments = [];
 
-    for (let segmentIndex = 0; segmentIndex < userCPUCount; segmentIndex++) {
-      const start = segmentIndex * segmentSize;
-      const end = start + segmentSize;
-      const segment = numbers.slice(start, end);
-      segments.push(segment);
-    }
+  console.log(numbers.length, userCPUCount, segmentSize);
+
+  for (let segmentIndex = 0; segmentIndex < userCPUCount; segmentIndex++) {
+    const start = segmentIndex * segmentSize;
+    const end = start + segmentSize;
+    const segment = numbers.slice(start, end);
+    segments.push(segment);
+  }
 
-    try {
-      const results = await Promise.all(
-        segments.map(
-          segment =>
-            new Promise((resolve, reject) => {
-              const worker = new Worker(workerPath, {
-                workerData: segment,
-              });
-              worker.on('message', resolve);
-              worker.on('error', reject);
-              worker.on('exit', code => {
-                if (code !== 0) reject(new Error(`Worker stopped with exit code ${code}`));
-              });
-            })
-        )
-      );
+  var promises = segments.map(
+    segment =>
+      new Promise((resolve, reject) => {
+        const worker = new Worker(workerPath, {
+          workerData: segment,
+        });
+        worker.on('message', resolve);
+        worker.on('error', reject);
+        worker.on('exit', code => {
+          if (code !== 0) reject(new Error(`Worker stopped with exit code ${code}`));
+        });
+      })
+  )
 
-      const finalResult = results.reduce((acc, val) => acc * val, 1n);
-      parentResolve(finalResult);
-    } catch (e) {
-      parentReject(e);
-    }
+  return Promise.all(promises).then(results => {
+    return results.reduce((acc, val) => acc * val, 1n);
   });
 };