ECMAScript 2017 (ES8)

Welcome to TheCodingCollege.com! ECMAScript 2017 (commonly referred to as ES8) introduced several powerful features that make JavaScript more versatile and developer-friendly. These enhancements streamline asynchronous programming, object manipulation, and string handling, making ES8 a valuable update.

In this guide, we’ll cover:

  1. What ES8 introduced to JavaScript.
  2. Practical examples of its features.
  3. How ES8 improves coding efficiency.

Key Features of ECMAScript 2017

  1. Async/Await for Asynchronous Programming
  2. Object.entries() and Object.values()
  3. String Padding (padStart() and padEnd())
  4. Trailing Commas in Function Parameters and Calls

1. Async/Await: Simplified Asynchronous Programming

The async and await keywords provide a cleaner and more readable way to handle asynchronous operations, replacing complex .then() chains from Promises.

Syntax:

  • async: Declares a function as asynchronous.
  • await: Pauses execution inside an async function until a Promise is resolved.

Example:

const fetchData = () =>
  new Promise((resolve) => {
    setTimeout(() => resolve("Data fetched!"), 1000);
  });

// Using Async/Await
async function getData() {
  console.log("Fetching data...");
  const result = await fetchData();
  console.log(result); // Data fetched!
}

getData();

Benefits:

  • Improved Readability: Async code looks synchronous.
  • Error Handling: Use try-catch for cleaner error management. 
async function fetchWithErrorHandling() {
  try {
    const data = await fetchData();
    console.log(data);
  } catch (error) {
    console.error("Error:", error);
  }
}

2. Object.entries() and Object.values()

These methods simplify working with objects by providing easy ways to retrieve their keys, values, or both.

Object.entries(): Returns an array of key-value pairs.

const user = { name: "Alice", age: 25 };
console.log(Object.entries(user)); 
// [['name', 'Alice'], ['age', 25]]

Object.values(): Returns an array of values.

console.log(Object.values(user)); 
// ['Alice', 25]

Use Cases:

  • Iterate Over Objects: 
Object.entries(user).forEach(([key, value]) => {
  console.log(`${key}: ${value}`);
});
// Output:
// name: Alice
// age: 25

3. String Padding: padStart() and padEnd()

These methods make it easy to pad strings to a desired length with a specific character.

padStart(): Pads at the beginning.

const id = "7";
console.log(id.padStart(3, "0")); // '007'

padEnd(): Pads at the end.

const price = "5";
console.log(price.padEnd(4, "$")); // '5$$$'

Benefits:

  • Useful for formatting output (e.g., aligning numbers, creating identifiers).

4. Trailing Commas in Function Parameters and Calls

ES8 allows you to add trailing commas in function parameter lists and calls, improving readability and making version control cleaner.

Example:

function sum(a, b, c,) {
  return a + b + c;
}

console.log(sum(1, 2, 3,)); // 6

Why It Matters:

  • Trailing commas reduce syntax errors when modifying code.

Why Use ECMAScript 2017?

  1. Cleaner Asynchronous Code: async/await transforms how we write and debug asynchronous operations.
  2. Easier Object Manipulation: Object.entries() and Object.values() simplify iterating through objects.
  3. Enhanced String Utilities: String padding is ideal for formatting output.
  4. Future-Proof Code: ES8 features are fully supported in modern environments, ensuring compatibility.

Learn ECMAScript 2017 with TheCodingCollege.com

At TheCodingCollege.com, we help developers:

  • Stay up-to-date with the latest JavaScript features.
  • Understand how to use new tools for practical coding tasks.
  • Build better, faster, and more efficient applications.

Conclusion

ECMAScript 2017 brought powerful tools to JavaScript, making it easier to write clean, efficient, and maintainable code. Whether you’re managing asynchronous operations or working with objects, ES8’s features enhance your workflow.

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