$functions */ private $functions = []; public function getCollected(): array { $list = array_keys($this->functions); natcasesort($list); return array_values($list); } public function enterNode(Node $node) { if ($node instanceof Node\Expr\FuncCall) { if (!empty($node->name) && $node->name instanceof Node\Name) { $this->functions[$node->name->toString()] = true; } } return null; } }