Lisphp_List::car PHP Method

    public function car()
    {
        return isset($this[0]) ? $this[0] : null;
    }

 public function apply(Lisphp_Scope $scope, Lisphp_List $arguments)
 {
     $vars = $arguments->car();
     $scope = new Lisphp_Scope($scope);
     foreach ($vars as $var) {
         list($var, $value) = $var;
         $scope->let($var, $value->evaluate($scope->superscope));
     }
     foreach ($arguments->cdr() as $form) {
         $retval = $form->evaluate($scope);
     }
     return $retval;
 }