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How ChatGPT Can Be Your JavaScript Coding Buddy
I have been reading this book "Modern Javascript for the Impatient", chapter "Object-Oriented Programming". At the end there is an "Exercise" section. This is a question from it I need help answering: *** Harry tries this code to toggle a CSS class when a button is clicked: ``` const button = document.getElementById('button1') button.addEventListener('click', function () { this.classList.toggle('clicked') }) ``` It doesn’t work. Why? Sally, after searching the wisdom of the Internet, suggests: ``` button.addEventListener('click', event => { event.target.classList.toggle('clicked') }) ``` This works, but Harry feels it is cheating a bit. What if the listener hadn’t produced the button as event.target? Fix the code so that you use neither this nor the event parameter. ***
I have been reading a book on JS. This is one of the questions at the end of a chapter that stumped me; don't know where to begin. So please help me out: _Question_ A classic example for an abstract class is a tree node. There are two kinds of nodes: those with children (parents) and those without (leaves). ``` class Node { depth() { throw Error("abstract method") } } class Parent extends Node { constructor(value, children) { . . . } depth() { return 1 + Math.max(...children.map(n => n.depth())) } } class Leaf extends Node { constructor(value) { . . . } depth() { return 1 } } ``` This is how you would model tree nodes in Java or C++. But in JavaScript, you don’t need an abstract class to be able to invoke n.depth(). **Rewrite the classes without inheritance and provide a test program.** So, how to write this code without using inheritance in JS?
