<?php /* * Signature mismatch during inheritance has been reclassified * as an E_WARNING error in PHP 7. A similar mismatch with an * interface or abstract method triggers a fatal error. */ class Base { public function greet() { echo 'Hello, world!'; } } class SubClass extends Base { public function greet($input) { echo "Hello, {$input}!"; } } $object = new SubClass(); $object->greet('David');