This is one thing I don’t see a lot of, maybe I’m looking at the wrong code or projects? But PHP traits have been around for years. Let’s have a look at them.

Traits are a mechanism for code reuse in single inheritance languages like PHP. They allow you to group methods and properties that you can use across multiple classes, without forcing you into the constraints of traditional inheritance. Essentially, traits allow you to “mix in” functionality to different classes, providing a flexible way to share behavior among classes.

How Traits Work

A trait is similar to a class, but it is not intended to be instantiated on its own. Instead, traits are designed to be included in classes using the use keyword. When a class uses a trait, it effectively incorporates the methods and properties defined in that trait as if they were defined in the class itself.

Key Features of Traits

Code Reuse Without Inheritance

Traits allow you to reuse code without relying on class inheritance. This is particularly useful when different classes need similar functionality but are not related through inheritance.

Combining Multiple Traits

A class can use multiple traits, which allows it to inherit a variety of methods and properties from different sources.

trait Logger {
    public function log(string $message) {
        echo "[LOG]: " . $message;
    }
}

trait Notifier {
    public function notify(string $message) {
        echo "[NOTIFY]: " . $message;
    }
}

class User {
    use Logger, Notifier;

    public function createUser(string $name) {
        $this->log("User '{$name}' created.");
        $this->notify("Notify user '{$name}'.");
    }
}

$user = new User();
$user->createUser("Alice");

The User class uses both the Logger and Notifier traits, allowing it to log and notify without needing to inherit from a common base class.

When to Use Traits

Traits are particularly useful in the following scenarios:

Code Reuse Across Unrelated Classes

When you need to share functionality among classes that don’t share a common ancestor, traits provide a clean solution.

Avoiding Inheritance Limitations

If your class already extends another class, traits allow you to add additional behaviour without needing multiple inheritance (which PHP does not support).

Reducing Code Duplication

Traits help to reduce code duplication by allowing you to define common methods in a single place and reuse them across multiple classes.

If you haven’t already explored traits in your PHP projects, now is a great time to start incorporating them into your codebase for more modular and reusable code. I will be writing helper traits in to my small custom MVC framework for things like logging, alerts and maybe even standard features like fetching RESTapi endpoints – The list is endless.