John Larsen - Get Programming with JavaScript

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ISBN: 9781617293108

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When John emailed me to ask if I would write a foreword for Get Programming with JavaScript, I have to admit the main thing that got me on the hook was that he had used JS Bin throughout the book to let readers try out live demos. JS Bin was created in 2008 as a place for programmers to collaborate, test, debug, experiment, and share. Education is close to JS Bins heart, so Johns background as a teacher and his practical approach seemed like a great fit with its ethos and purpose. Im a firm believer that getting your hands dirty with real code is a great way to learn, and being encouraged to create, extend, play, and rewrite, all in a safe, no-mistakes-barred space, looked like a good idea for a beginners programming book.

As the developer of JS Bin, an application created with JavaScript, Im always excited to see JS Bin being used to teach beginners, and thats exactly what John does with this book. It goes without saying that different people in different contexts take different lengths of time to learn programming. But they all benefit from a practical approach. JS Bin, as a free resource requiring no installation, provides an instantly accessible environment in which to learn, and this book provides the guidance to get started, the support to keep practicing, and the encouragement to enjoy the adventure.

I remember seeing object dot notation well over 10 years ago and wondering how I was supposed to Google What does . mean? If Id had Johns gentle and thorough introduction to JavaScript back then, I would have saved myself a lot of pain wading through many failed search attempts! He doesnt cover everything, but he takes his time with key concepts, showing patience and consideration for readers and encouraging them to stretch their knowledge and build their skills. The variety of examples really helps; theres lots to get your teeth into, but also plenty of support and suggestions for further practice. Dont get lost in The Crypttrust your guide. It builds into a substantial project and should help you see how little pieces can make big apps.

Ive had the privilege of creating a number of tools for the programmer community, and a number of JavaScript tools in particular. Programming lets us make things for fun, for profit, and for others, and its wonderful to welcome newcomers to the fold; who knows what great ideas theyll have as they build the next big thing (or the next small thing!)? Im thrilled that their first steps on such an exciting path will be on JS Bin. Welcome! Create bins for your code, tinker, share, and build up your bank of modules. Get Programming with JavaScript shows you how to manage your code bins and combine them into bigger projects. (You even get to play with the HTML and CSS panels on JS Bin!)

Enjoy the book, dear reader. I expect that by the end of it, youll have a firm grasp of how to write JavaScript.

R emy S harp

F ounder of JS B in

I started programming using the BASIC language on a Commodore VIC-20 in 1982. It had 3.5 KB of RAM, and programming involved me copying a program from a magazine, instruction by instruction and line by line. The process was time-consuming and error-prone, but it certainly built focus and attention to detail! Rather than cut-and-paste, it was read-and-type; but eventually, the program was transferred from the printed page to the computers memory. Then the moment of truth ... and alas, it never worked the first time. And thats where my learning really began.

Staring at the code, trying to make sense of the instructions and follow the flow of the program as it jumped from line to line, I had to think carefully and patiently about what was going on. Not everything made sensesometimes squeezing a program into 3.5 KB required some seriously supple code gymnasticsbut, bit by bit, the programs secrets would start to reveal themselves. Sometimes my typos stopped the program from running; sometimes there were mistakes in the code itself. Most of the time, but not always, I eventually got the program to run.

Half the time, the program would turn out to be rubbish! Id reach out and hit the VIC-20s off switch, and the program would be gone forever. (It took five minutes and a cassette-tape recorder to save, and some programs just werent worth it.) I wasnt usually upset, and I didnt see it as a waste of time; from the start, I was amazed by the transformation of text into a working program (even a rubbish one) on the computer screen.

Today, in 2016, with our smartphones, tablets, drones, and AI Go champions, that sense of wonder has grown even stronger. Programming is magical and transformative. Even knowing how it works, I still love how my typed instructions turn into a working website, a fun game, or a useful utility.

As a teacher in the United Kingdom, Im privileged to be able to teach 16- and 17-year-olds programming. My philosophy is to let them get programming from lesson one: to enter code and see the result as soon as possible. I want them to be curious and experiment at all times. Its great to see their eyes widen and their smiles grow as they start their adventures in code and realize they can convert imagination into reality. Online code-editing environments such as JS Bin allow them to quickly try out ideas and build projects piece by piece. They dont learn a long list of language features before beginning; they learn a few concepts at a time, often in response to getting stuck but also directly from me (they dont know what they dont know), and they practice and experiment before moving on. Their skills build day by day and week by week, and code that might have seemed like cryptic hieroglyphs at the start of the course becomes second nature by the end. Its great to be a part of that learning process.