Closure: The Definitive Guide

Foreword

Nick Santos

Former Closure Compiler Tech Lead

I was sitting on a balcony on the west side of Manhattan, sipping on a warm glass of scotch with a few others. Michael Bolin joined us. Michael wrote this book. At the time, Michael was working on Google Tasks. I was the tech lead on our JavaScript optimizer, later named Closure Compiler. Michael didn’t join us to talk about JavaScript optimization though. He didn’t want to talk scotch either, to his detriment. He wanted to talk JavaScript-driven text editing, and thus he wanted to talk to Julie.

You will receive a proper introduction to Julie in Chapter 9, but for now, just know that Julie is our expert on how text editors are implemented in each web browser.

Michael found that, when managing a task list in a web browser, you want a few features built into your plain text editor. You want to make words bold for emphasis. You want a keyboard shortcut to move your cursor to the next task item. He didn’t want to have to write a whole editor. He just wanted a few tweaks on top of what the browser provides, to make the experience smoother for the user. How would you implement this?

Julie explained that there are many, many choices for such a thing. “Should you use a textarea?” “Should you use a contentEditable region?” “Should you rely on the browser’s built-in rich text functions?” “Should you implement the ‘bold’ function in JavaScript?” “How do you make sure the cursor ends up on the right line, given that browsers each implement ...