public static function userPainSort(entities\Issue $first_issue, entities\Issue $second_issue) { $first_issue_pain = $first_issue->getUserPain(); $second_issue_pain = $second_issue->getUserPain(); if ($first_issue_pain == $second_issue_pain) { return 0; } return $first_issue_pain < $second_issue_pain ? -1 : 1; }