Next-method

When a generic function is called, the list of applicable methods is built. As mentioned before, the most specific method of this list is applied (see [*]). This method may call the next method in the list of applicable methods. This is done by using the special form next-method. Consider the following definitions
\begin{scheme}
(define-method Test((a <integer>)) (cons 'integer (next-method)))...
...) (cons 'number (next-method)))
(define-method Test(a) (list 'top))
\end{scheme}

With those definitions,
\begin{scheme}
(Test 1) \lev (integer number top)
(Test 1.0) \lev (number top)
(Test \schtrue) \lev (top)
\end{scheme}