name = $name; $this->callback = $callback; $this->dependentMetrics = $dependentMetrics; } public function getName() { return $this->name; } public function compute(Row $row) { if ($this->callback) { return call_user_func($this->callback, $row); } } public function getTranslatedName() { return ''; } public function getDependentMetrics() { return $this->dependentMetrics; } }