Michel Jonkman

Though I'd prefer only allowing the syntax with parentheses like set($value)

It could be nice addition to creating DTOs objects in PHP with "virtual" properties:

readonly final class SomeDto
{
    public function __construct(
        public string $name,
        public string $surname,
        public string $fullName {
            get => ucfirst($this->name) . ' ' . ucfirst($this->surname);
        }
    ) {
    }
}

or even shorter version:

readonly final class SomeDto
{
    public function __construct(
        public string $name,
        public string $surname,
        public string $fullName => ucfirst($this->name) . ' ' . ucfirst($this->surname),
    ) {
    }
}

Nice addition, but I would change syntax:

class User 
{
    public string $name {
        set($value) {
            if (strlen($value) === 0) {
                throw new ValueError("Name must be non-empty");
            }
            return $value;
        }
    }
 
    public function __construct(string $name) {
        $this->name = $name;
    }
}

This is good to have.

Properties are useful for exchanging (reading and writing) single values. Properties are good for data binding, etc.

With this RFC we can implement:

• Validation
• Trigger events
• Call methods if there is more to do

Update: About the $field I am not sure. Having a separate backing field can have some advantages.