Multiple Inheritance

Multiple Inheritance — a practical guide to multiple inheritance PHP with clear examples you can reuse in real projects.

OOP Tutorial Series (21/65). Prefer one article? Read the complete OOP tutorial.

Short description

PHP does not allow extending multiple classes. Implement multiple interfaces and use traits for shared code.

Interfaces + trait

interface Loggable { public function log(string $msg): void; }
interface Cacheable { public function cacheKey(): string; }
trait WritesLog {
    public function log(string $msg): void { echo $msg; }
}
class Report implements Loggable, Cacheable {
    use WritesLog;
    public function cacheKey(): string { return 'report'; }
}