This post is part 45 of 45 in the series Programming by Stealth

We’ll start this instalment be re-visting the question of when to use let and when to use const for variable declarations. My initial advice was to default to using let, but based on some great feedback from the the community, I’ve changed my mind, and will be defaulting to const going forward. I’ll explain why I changed my mind.

Next we’ll have a quick look at my sample solution to the challenge set at the end of the previous instalment, before moving on to some new material. Specifically, we’ll look at some of the ways in which ES6 has improved arrays and strings.

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This post is part 44 of 45 in the series Programming by Stealth

In the previous instalment we started our exploration of the new features ES6 brought to JavaScript with a look at block scoped variables. We learned that var will continue to work as it always has, defining function-scoped variables, but that we can now use let and const to define block-spoped variables and constants.

We’ll continue our exploration of ES6 today by looking at how function arguments have been improved, and learning about a new type of loop designed to make looping over object properties easier.

There is no ZIP file for this instalment, instead, I’ve published my solution to the challenge from the previous instalment (which is also the starting point for the next challenge) as a tagged release on GitHub. You can download it using the big green button labeled Clone or Download.

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This post is part 43 of 45 in the series Programming by Stealth

Because its been a while since we focused on JavaScript, the bulk of this instalment will focus on solving the challenge set at the end of the previous instalment. We’ll work through the solution in detail, step-by-step.

We’ll finish the instalment by making a start on moving from JavaScript version 5, to JavaScript version 6, or ECMAScript 6, usually just called ES6. When we started our look at JavaScript about a year and a half ago it made sense to use JavaScript 5, but now it’s time to upgrade our knowledge. ES6 was a very big change indeed, so we won’t bit it all off at once. Instead, we’ll focus on just one very important change in this instalment — ES6’s new take on variables.

There’s no zip file for this instalment as such, instead, I’ve published my sample solution as a tagged release on GitHub instead. You can use the big green clone or download button to either copy the code using GIT, or download it as a ZIP file.

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This post is part 42 of 45 in the series Programming by Stealth

In this instalment it’s finally time to bring our Cellular Automaton prototypes to life by implementing Conway’s Game of Life. By the end of this instalment we’ll have reached a real milestone — our first web app! Granted, it won’t be a very feature-rich web app, but you have to start somewhere!

As usual, I’ve collected the code files for this instalment into a ZIP file which you can download here. As well as the ZIP file, I’ve also published a tagged release of the bartificer.ca.js code on GitHub which you’ll need for this instalment’s challenge.

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This post is part 41 of 45 in the series Programming by Stealth

In this instalment we’ll tie up the last few loose ends related to web forms. With web forms under our belts, we’ll then be ready to pick up where we left off with our cellular automata JavaScript prototypes, and combine our HTML, JavaScript, and CSS skills together to make our first web app – an implementation of Conway’s Game of Life.

This instalment breaks down into two distinct parts – our first look at keyboard interaction with web forms, and a final look at form-related events.

When it comes to keyboard interaction we’ll start by looking at how browsers treat regular web forms, and then we’ll move on to supporting keyboard interaction with custom web form UI elements like the star-rating example from instalment 36.

Finally, we’ll wrap up with a handy reference table summarising the most important webform-related JavaScripts events, giving some guidance on their use.

There’s just one sample file associated with this instalment, and it’s available for download as a ZIP file here.

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This post is part 40 of 45 in the series Programming by Stealth

At the end of the previous instalment I promised we were done with HTML form validation, and insisted we were ready to move on to finishing our Cellular Automata, but it turns out that was a little premature. While working on my sample solution for the previous instalment‘s challenge I realised I’d forgotten to cover something very important – the fact that you can use jQuery to deal with situations where the HTML5 form validation attributes are not powerful enough for your needs. So – we need to rectify that oversight, and that’s going to take this entire instalment to do.

Then, while doing her homework, Allison discovered another oversight that needs to be remedied before we move away from HTML forms – we need to look at how to support keyboard-only interactions. Why? In a word – accessibility. So, in the next instalment we’ll start by looking at the narrow case of supporting keyboard input in forms, but we’ll then move on and look at keyboard interactions a little more broadly, and we’ll learn how to add keyboard shortcuts to our web apps. This will come in useful when we do then finally move on to getting our cellular automata working the following instalment.

As usual, I’ve collected all the files for this instalment into a single ZIP file which you can download here.

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This post is part 39 of 45 in the series Programming by Stealth

In this instalment we’ll be taking a break from our parallel approach, and focusing almost exclusively on HTML5 form validation. We’ll dedicate the entirety of the next instalment to getting our cellular automaton prototypes up and running so we can actually ‘play’ the game of life.

While we won’t be continuing work on our Cellular Automata prototypes this time, I will share my solution to the challenge I set way back in instalment 36.

Also, before we get stuck into new content I’ll be taking a small diversion to explain a slight change in my approach to HTML coding, and how that will affect the sample code you see for the remainder of this series.

As usual, I’ve collected the example file for this instalment and the starting point for the challenge together into a ZIP file which you can download here.

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This post is part 38 of 45 in the series Programming by Stealth

Since this is the first instalment back after our summer hiatus, it seems like a good time to pause and take stock. I want to look back to revise what we’ve learned to far, and, to look forward to where I want to take this series next.

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This post is part 37 of 45 in the series Programming by Stealth

In this instalment we take a break from what we’ve been doing to take an in-depth look at code documentation. I’ve regularly included documentation generated with JSDoc as one of the inputs to the challenges, and I’ve done so with the implicit assumption that those docs would be intuitively meaningful to you all. Talking with Allison two things became clear to me – firstly, that I had made this implicit assumption, and secondly, that it was completely wrong! Code documentation is a lot like man pages on the terminal – the structure of how the words are presented often carry as much meaning as the words themselves. With decades of experience this is obvious, but it’s not intuitively obvious to novices.

To remedy this I thought it would be useful to go through the entire cycle of documenting one function, and that the appropriate format for that was a screencast. When I sat down to record the screencast I couldn’t help but use the opportunity to share my toolkit with you all, so the screencast starts with a little demo of the development tools I’m currently using to develop the Cellular Automaton API we’re working on as part of this series.

Below you’ll find the screencast embedded, and, links to the various tools mentioned. Myself and Allison have also recorded a podcast for this instalment. I share my screen with Allison, and we walk through all the same steps as I do in the screencast, but with Allison stopping me and asking all the questions you probably are as you watch the screencast. When published, that podcast will be linked into this post.

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This post is part 36 of 45 in the series Programming by Stealth

In the previous instalment we took at first look at text input in HTML, and we made a start on a new project – building a set of JavaScript prototypes for creating cellular automata so we can implement Conway’s Game of Life. In this instalment we’ll continue down both of those paths. Later in the project the two paths will finally merge when we use web forms to build a UI around our game of life.

We’ll start on the HTML track where we move on from generic text input with single and multi-line basic text boxes to some more specific types of text input, including some nice new input types that HTML 5 brought to the table. This will set up up to learn about HTML 5 form validation in the next instalment.

When we switch to the JavaScript track we’ll start by having a quick look at my sample solution to the previous instalment. Then, we’ll make a start on a JavaScript prototype to represent a Cellular Automaton together, which will set up the next assignment.

I’ve zipped up my solution to the previous assignment, a sample file that accompanies this instalment, and the starting point for the next assignment which you can download here.

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