Online PHP editor | refs for JKpi5

<?php $user = (object) [ 'roles' => [ 'student', //remove 'grade_1_student', 'grade_4_student', 'grade_some_student', //remove 'arbitrarty-0', //remove 'grade_9_student', ], ]; function getStudentGradesFromRoles(array $roles) { return array_values(preg_filter('/^(grade)_(\d)_student$/', '$1-$2', $roles) ?: []); } $grades = getStudentGradesFromRoles((array) $user->roles); var_dump($grades);