Improve examples

Author: tshemsedinov

JavaScript/1-sync-try.js

@@ -7,18 +7,20 @@ const sum = (a, b) => {
   throw new Error('a and b should be numbers');
 };
 
+const x = 2;
+const y = 3;
 try {
-  console.log(sum(2, 3));
+  const total = sum(x, y);
+  console.log({ x, y, total });
 } catch (err) {
-  console.log(err.message);
+  console.error({ x, y, err });
 }
 
+const z = 7;
+const c = 'A';
 try {
-  console.log(sum(7, 'A'));
+  const res = sum(z, c);
+  console.log({ z, c, res });
 } catch (err) {
-  console.log(err.message);
+  console.error({ z, c, err });
 }
-
-console.log(sum(7, 'A'));
-
-console.log('Not executed');

JavaScript/2-sync-tuple.js

@@ -7,6 +7,18 @@ const sum = (a, b) => {
   return [new Error('a and b should be numbers')];
 };
 
-console.log(sum(2, 3));
+{
+  const x = 2;
+  const y = 3;
+  const [err, total] = sum(x, y);
+  if (err) console.error({ x, y, err, total });
+  else console.log({ x, y, err, total });
+}
 
-console.log(sum(7, 'A'));
+{
+  const z = 7;
+  const c = 'A';
+  const [err, res = NaN] = sum(z, c);
+  if (err) console.error({ z, c, err, res });
+  else console.log({ z, c, err, res });
+}

JavaScript/3-async.js

@@ -8,18 +8,22 @@ const sum = (a, b, callback) => {
   }
 };
 
-sum(2, 3, (err, result) => {
+const x = 2;
+const y = 3;
+sum(x, y, (err, total) => {
   if (err) {
-    console.log(err.message);
+    console.error({ x, y, err });
     return;
   }
-  console.log(result);
+  console.log({ x, y, total });
 });
 
-sum(7, 'A', (err, result) => {
+const z = 7;
+const c = 'A';
+sum(z, c, (err, res) => {
   if (err) {
-    console.log(err.message);
+    console.error({ z, c, err });
     return;
   }
-  console.log(result);
+  console.log({ z, c, res });
 });

JavaScript/4-uncaught.js

@@ -12,5 +12,16 @@ const sum = (a, b) => {
   throw new Error('a and b should be numbers');
 };
 
-console.log(sum(2, 3));
-console.log(sum(7, 'A'));
+{
+  const x = 2;
+  const y = 3;
+  const total = sum(x, y);
+  console.log({ x, y, total });
+}
+
+{
+  const z = 7;
+  const c = 'A';
+  const res = sum(z, c);
+  console.log({ z, c, res });
+}

JavaScript/5-promise.js

@@ -1,33 +1,37 @@
 'use strict';
 
-const sum = (a, b) => new Promise((resolve, reject) => {
+const sum = (a, b) => new Promise((totalolve, reject) => {
   if (typeof a === 'number' && typeof b === 'number') {
-    resolve(a + b);
+    totalolve(a + b);
   } else {
     reject(new Error('a and b should be numbers'));
   }
 });
 
-sum(2, 3)
-  .then((data) => {
-    console.log(data);
+const x = 2;
+const y = 3;
+sum(x, y)
+  .then((total) => {
+    console.log({ x, y, total });
   })
   .catch((err) => {
-    console.log(err.message);
+    console.error({ x, y, err });
   });
 
-sum(7, 'A')
-  .then((data) => {
-    console.log(data);
+const z = 7;
+const c = 'A';
+sum(z, c)
+  .then((res) => {
+    console.log({ z, c, res });
   })
   .catch((err) => {
-    console.log(err.message);
+    console.log({ z, c, err });
   });
 
 /*
-sum(7, 'A')
-  .then(data => {
-    console.log(data);
+sum(z, c)
+  .then((res) => {
+    console.log({ z, c, res });
   });
 
 UnhandledPromiseRejectionWarning: Error: a and b should be numbers

JavaScript/6-async-await.js

@@ -9,25 +9,33 @@ const sum = async (a, b) => {
 
 (async () => {
 
+  const x = 2;
+  const y = 3;
   try {
-    console.log(await sum(2, 3));
-  } catch (e) {
-    console.log(e.message);
+    const total = await sum(x, y);
+    console.log({ x, y, total });
+  } catch (err) {
+    console.error({ x, y, err });
   }
 
+  const z = 7;
+  const c = 'A';
   try {
-    console.log(await sum(7, 'A'));
+    const res = await sum(z, c);
+    console.log({ z, c, res });
   } catch (err) {
-    console.log(err.message);
+    console.error({ z, c, err });
   }
 
   /*
-  console.log(await sum(7, 'A'));
+  const res = await sum(z, c);
+  console.log({ z, c, res });
 
   UnhandledPromiseRejectionWarning: Error: a and b should be numbers
 
   DeprecationWarning: Unhandled promise rejections are deprecated.
   In the future, promise rejections that are not handled will terminate
   the Node.js process with a non-zero exit code.
   */
+
 })();