Check if Process Arguments Contain Flags

Introduction

In this lab, we will explore how to check if process arguments contain flags using JavaScript. You will learn how to use the Array.prototype.every() and Array.prototype.includes() methods to check if the specified flags are present in the process.argv array. Additionally, you will learn how to use regular expressions to prefix the specified flags with - or -- as needed. This lab will help you improve your understanding of JavaScript and how to work with command-line arguments in Node.js.

Skills Graph

Check if Process Arguments Contain Flags

To check if the current process's arguments contain specified flags, follow these steps:

1. Open the Terminal/SSH and type node to start practicing coding.
2. Use Array.prototype.every() and Array.prototype.includes() to check if process.argv contains all the specified flags.
3. Use a regular expression to test if the specified flags are prefixed with - or -- and prefix them accordingly.

Here's a code snippet that shows how to implement this:

const hasFlags = (...flags) =>
  flags.every((flag) =>
    process.argv.includes(/^-{1,2}/.test(flag) ? flag : "--" + flag)
  );

You can test the function with different flags like this:

// node myScript.js -s --test --cool=true
hasFlags("-s"); // true
hasFlags("--test", "cool=true", "-s"); // true
hasFlags("special"); // false

Summary

Congratulations! You have completed the Check if Process Arguments Contain Flags lab. You can practice more labs in LabEx to improve your skills.