This post is part 19 of 19 in the series Programming by Stealth

While recording instalment 18 of the Programming by Stealth series, I promised Allison some challenges to help listeners test and hone their understanding of the core JavaScript language. Since we’ve now covered pretty much the whole language in the series, it’s the perfect time to pause and consolidate that knowledge.

These challenges are designed to be run in the PBS JavaScript Playground. You may also find the PBS JavaScript cheatsheet helpful.

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This post is part 18 of 19 in the series Programming by Stealth

We’ve now covered most of the core JavaScript language. We’ve learned that variables can store literal values, or references to objects. We’ve learned there are three types of literal values – numbers, booleans, and strings. We’ve learned about operators. We’ve learned about conditionals. We’ve learned about loops of various sorts, and we’ve learned about objects. We’ve learned that in JavaScript, arrays are implemented as objects with the prototype Array, and that functions are also implemented as objects.

Before we can leave the playground and head off into the world of the browser, we just have a few more loose ends to tie up, which we’ll take care of in this instalment.

Now that we know about objects, we need to re-visit the arguments object present in every JavaScript function. We need to take a detailed look at the typeof operator, and we need to look at some built-in objects and functions JavaScript provides.

We also need to look at how JavaScript handles regular expressions, and finally, we need to introduce the concept of exception handling.

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This post is part 16 of 19 in the series Programming by Stealth

In the previous instalment we introduced the concept of JavaScript functions. We learned how to all existing functions, and how to create out own.

In this instalment we’re going to take our understanding of functions to the next level. The techniques we encounter today would be considered advanced techniques in most other languages, and you could spend years developing in Java and never encounter an anonymous function. However, because of how JavaScript is integrated into HTML documents, these techniques are considered fundamental in JavaScript, and anonymous functions are a dime a dozen!

Before we delve into anonymous functions, we’ll start by taking a deeper look at how JavaScript deals with function arguments.

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This post is part 15 of 19 in the series Programming by Stealth

At this stage we’ve learned about five key components to any programming language, and how they are implemented in JavaScript – variables, operators, branching, arrays, and loops. Now it’s time to add another – functions.

A function is a collection of statements that is given a name so it can be easily re-used. We’ve already used functions, but without knowing that’s what we’ve been doing.

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This post is part 14 of 19 in the series Programming by Stealth

At this stage we’ve learned about three of the key components common to just about every programming language, and how they’re implemented in JavaScript – variables, operators, and branching. Now it’s time to add two more – arrays, and loops.

Arrays store a list of related data in a single variable, and loops allow us to apply the same action over and over again. To process an arbitrarily long array, you need some kind of iteration, and loops are the simplest way of achieving that.

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This post is part 13 of 19 in the series Programming by Stealth

In the previous instalment we got our first taste of JavaScript. We learned about variables, literal data types, and some basic string and arithmetic operators. In this instalment we’re going to focus on booleans. We’ll look at how non-boolean values get converted to booleans when needed (e.g. is 'boogers' true or false?), we’ll learn about some comparison operators that result in boolean values, and we’ll learn about some logical operators. At that stage we’ll have all the knowledge we need to learn about our third fundamental programming concept – branching.

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This post is part 12 of 19 in the series Programming by Stealth

With this instalment we’re starting into a whole new phase of the series. We’ve looked at using HTML to define the structure of an HTML document, and then we moved on to looking at CSS for defining the look of an HTML document, and now we’re going to move on to JavaScript to add interactivity to HTML documents.

Learning the basics of JavaScript, and learning how to connect JavaScript into the browser environment are two very different tasks, so, we’re going to separate them. We’ll start by learning some JavaScript fundamentals in a JavaScript playground I’ve created. Only when we know enough JavaScript for the mechanics of the browser’s JavaScript integration to make sense will we move tackle the so-called DOM, and the browser event model.

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This post is part 11 of 19 in the series Programming by Stealth

Finally, after many months of making Allison wait, it’s time to look at tables on web pages. We’ll start by describing the HTML markup for tables, and then look at how to style them with CSS.

Remember – tables are for one thing, and one thing only – displaying tabular data!

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This post is part 10 of 19 in the series Programming by Stealth

Continuing our look at CSS, in this instalment we’ll start by looking at how to style lists, then we’ll move on to look at some more CSS selectors, and we’ll finish with an introduction to a new CSS concept – pseudo-classes.

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This post is part 9 of 19 in the series Programming by Stealth

In the previous instalment we learned how to group multiple HTML tags together to define regions within a page, and then how to move those regions around by floating them, or positioning them explicitly. We’ll start this instalment with a little revision – there was a lot to digest last time! While re-visiting the layout from last time, we’ll also look at some of its limitations, and then we’ll move on to look at the CSS display property, how it can be used to alter layouts, and, how we can use it to improve on our demo layout.

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