Online PHP editor | output for 8NkM9

<?php interface ConfigValueInterface { public function __toString(); } interface ConfigWriterInterface { public function write(ConfigValueInterface $value); } class WriteManager { protected $writers = []; public function addWriter(ConfigWriterInterface $writer, $value_class) { $this->writers[$value_class] = $writer; } public function write(ConfigValueInterface $value) { $class = get_class($value); if (isset($this->writers[$class])) { $this->writers[$class]->write($value); } } } class BaseConfigValue implements ConfigValueInterface { public $storage_location; public function __toString() { return "derp"; } } class NginxConfigValue extends BaseConfigValue {} class BaseConfigWriter implements ConfigWriterInterface { public function write(ConfigValueInterface $value) { if (!$value instanceof BaseConfigValue) { throw new \RuntimeException('Invalid value type'); } echo "writing to {$value->storage_location}\n"; } } class NginxConfigWriter implements ConfigWriterInterface { public function write(ConfigValueInterface $value) { if (!$value instanceof NginxConfigValue) { throw new \RuntimeException('Invalid value type'); } echo "writing NGINX config to {$value->storage_location}\n"; } } class ExampleGenerator { public function generate() { $value = new BaseConfigValue(); $value->storage_location = "/some/path/sample.config"; return $value; } } class NginxGenerator { public function generate() { $value = new NginxConfigValue(); $value->storage_location = "/some/path/sample.config"; return $value; } } // Set up manager $manager = new WriteManager(); $manager->addWriter(new BaseConfigWriter, BaseConfigValue::class); $manager->addWriter(new NginxConfigWriter, NginxConfigValue::class); $generator = new ExampleGenerator(); $value = $generator->generate(); $manager->write($value); $generator = new NginxGenerator(); $value = $generator->generate(); $manager->write($value);