public function check_external_forbidden_words($ct, $val, $words) { $a2 = array('a:x^2)', 'b:(sin(x)+1)^2'); $s2 = array(); foreach ($a2 as $s) { $s2[] = new stack_cas_casstring($s); } $cs2 = new stack_cas_session($s2, null, 0); $at1 = new stack_cas_text($ct, $cs2, 0); $this->assertEquals($val, $at1->check_external_forbidden_words($words)); }