Properties

Rule: Visibility (e.g., public, protected, private) MUST be declared on all properties.
Reason: Visibility modifiers help clarify how properties can be accessed and modified. Explicit visibility declarations improve code readability and maintainability.

class MyClass {
    public $name;
    protected $age;
    private $salary;
}

Rule: Type MUST be declared on all properties.
Reason: Declaring types for properties helps ensure type safety, prevents errors, and improves code clarity.

class MyClass {
    public string $name;
    protected int $age;
    private float $salary;
}

Rule: The var keyword MUST NOT be used to declare a property.
Reason: The var keyword is an outdated way of declaring properties, and modern PHP supports explicit visibility modifiers (public, protected, private) and type declarations.

Rule: There MUST NOT be more than one property declared per statement.
Reason: Declaring one property per statement improves code readability and makes it easier to add, modify, or remove properties in the future.

class MyClass {
    public string $name;
    private int $age;
}

class MyClass {
    public string $name, int $age;
}

Rule: Property names MUST NOT be prefixed with a single underscore to indicate protected or private visibility.
Reason: The underscore prefix explicitly has no meaning and can lead to confusion. Visibility should be indicated by the visibility modifier (public, protected, private), not by a naming convention.

class MyClass {
    private string $name;
}

class MyClass {
    private string $_name;
}

Rule: There MUST be a space between the type declaration and the property name.
Reason: This helps improve readability and aligns with modern PHP conventions.

class MyClass {
    public string $name;
    private int $age;
}

class MyClass {
    publicstring$name;
}