Book Image

The JavaScript Workshop

By : Joseph Labrecque, Jahred Love, Daniel Rosenbaum, Nick Turner, Gaurav Mehla, Alonzo L. Hosford, Florian Sloot, Philip Kirkbride
Book Image

The JavaScript Workshop

By: Joseph Labrecque, Jahred Love, Daniel Rosenbaum, Nick Turner, Gaurav Mehla, Alonzo L. Hosford, Florian Sloot, Philip Kirkbride

Overview of this book

If you're looking for a programming language to develop flexible and efficient apps, JavaScript is a great choice. However, while offering real benefits, the complexity of the entire JavaScript ecosystem can be overwhelming. This Workshop is a smarter way to learn JavaScript. It is specifically designed to cut through the noise and help build your JavaScript skills from scratch, while sparking your interest with engaging activities and clear explanations. Starting with explanations of JavaScript's fundamental programming concepts, this book will introduce the key tools, libraries and frameworks that programmers use in everyday development. You will then move on and see how to handle data, control the flow of information in an application, and create custom events. You'll explore the differences between client-side and server-side JavaScript, and expand your knowledge further by studying the different JavaScript development paradigms, including object-oriented and functional programming. By the end of this JavaScript book, you'll have the confidence and skills to tackle real-world JavaScript development problems that reflect the emerging requirements of the modern web.
Table of Contents (17 chapters)

11. Creating Clean and Maintainable Code

Activity 11.01: Expanding Phone Number Matching Patterns to Accept Multiple Formats

Solution:

  1. Observe that only the characters at the beginning of each pattern differ, but the last characters, XXX-XXXX, are the same in both patterns.
  2. For the differing characters, for our regex to match either format correctly, you can specify the regex snippets that correspond to each format as alternate expressions of an alternation. Recall that alternations take the form of (expression1|expression2):
        ([2-9]\d{2}-|\([2-9]\d{2}\) )
    where Regex for XXX-\Regex for (XXX)
  3. Combine it with the rest of the original regex to get the complete regex:
        ^([2-9]\d{2}-|\([2-9]\d{2}\) )\d{3}-\d{4}$
  4. Remember that the original regex, \d{3}-\d{4}, matches XXX-XXXX, which is the same for both patterns. We only needed the alternation for the beginning parts of each pattern that differed. The ^ and $ characters...