If you use object-oriented programming, there’s a good chance that you’re familiar with the constructor. It’s this special method that an object-oriented programming language uses to initialize a new object. In PHP (and a lot of other object-oriented programming languages), the
__construct method is a special method reserved for the role of constructor.
The role of the constructor isn’t always well understood. This is especially true when you’re new to object-oriented programming. You know the method exists, but you’re not too sure how to use it.
This can lead to some less than ideal practices around constructors. This is especially true in the WordPress world where two such practices are popular. First, there’s the habit of putting hooks in the constructor. And, because of that habit, WordPress developers tend to overuse the singleton pattern.
These two practices show a misunderstanding of the role that a constructor plays inside a class. This isn’t how object-oriented programming wants you to use constructors. There are other ways to solve those problems without sacrificing the role of a constructor.
Now, this isn’t to say that constructors don’t have any problems either. They do! In fact, that’s why we’re looking at the static factory method pattern. It solves one common problem that constructors have in PHP.