Errors in JavaScript

When a JavaScript engine reaches code that it cannot run, it stops what it is doing and reports the problem as an error. An error can stop a whole program, so a program that reads input from users, files, or other systems needs a plan for the errors that input can cause.

This chapter follows one small task from start to finish: a shop receives an order as text, turns the text into an object, checks it, and adds it to a cart. Every lesson uses that task, so you can see which errors appear at each step and how each tool in the chapter handles them