Labs are hands-on coding projects that you build along with Tonya as she explains the code, concepts, and thought processes behind it. You can use the labs to further your code knowledge or to use right in your projects. Each lab ties into the Docx to ensure you have the information you need.
Each lab is designed to further your understanding and mastery of code. You learn more about how to think about its construction, quality, maintainability, programmatic and logical thought, and problem-solving. While you may be building a specific thing, Tonya presents the why of it to make it adaptable far beyond that specific implementation, thereby giving you the means to make it your own, in any context.
Let’s dive into passing data by reference. By reference allows you to work with the same data between different variables. This means you can change the data and it is changed in both variables. You will build some code to test this concept and see how it works. Then you and I will talk about when to use it.
Let’s see how static variables retain their data within PHP internals.
Static variables retain their data even after the function gets done running. Then the next time you call it, it remembers the data it had from before because it is retained and persistent for the life of the web page request. Statics offer you an option instead of using global variables. Let’s take a look at how you can pass memory around in procedural coding without using globals. In this video, you will write code to show how the static and non-static variable work. You’ll build a for loop and then call two separate functions.
Let’s look at how PHP manages global variables and provides the scope. You’ll look again at memory.
The intent of global variables is to allow all of the code, all plugins and themes, to be able to both read and write to the variable. You want anything within the website’s PHP code to have full, unprotected access to the data that your variable represents. That means that any code within the website can change the data. For example, $wp_query is a global variable. Therefore, any piece of code in WordPress Core, plugins, and theme can both read and change the data.
Let’s talk about variable scope. Scope defines how and where you can access and use variables. It relates to memory. A variable within a function belongs to that function. Scoping is like a gatekeeper. It protects our code from other functions and code, to ensure we have control. It protects our variable naming to avoid naming conflicts.
The question I often get is: If I only need a couple of the arguments that a filter or action makes available, do I have to specify all of them in the callback function for add_filter() and add_action(). For example, if a filter, such as shortcode_atts_{$shortcode} has 4 arguments, but I only need 3, do I have to wire it up for all 4? In this video, Tonya explains why you have control over what you want to receive by looking into WordPress core at apply_filters().
Know the Code develops and empowers professional WordPress developers, like you. We help you to grow, innovate, and prosper.