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<?php class MyQuery{ public function query() { die('callable called'); } } class QueryHandler { public $query; public function setQuery(callable $query) { echo "checkpoint 1 reached"."\n"; $this->query = $query; } public function runQuery(){ $this->$query(); echo "end (should not show)"."\n"; } } echo "start"."\n"; $myQuery = new MyQuery; $queryHandler = new QueryHandler; $queryHandler->setQuery($myQuery->query()); $queryHandler->runQuery();
Output for 5.4.2 - 5.4.45, 5.5.24 - 5.5.35, 5.6.7 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
start callable called

preferences:
215.69 ms | 404 KiB | 251 Q