cs381k p. 79

Incremental Testing

Lisp allows subprograms to be tested directly by giving them test data. There is no need to write (compile, link) special programs for testing.


(s+ 0 'x)
X
(s+ 'x 0)
X
(s+ 2 3)
5
(s+ 'x 'y)
(+ X Y)

After similarly testing S*, we can try our example again:


(deriv '(+ (* m x) b) 'x)
M

Success! However, there are many other possible simplifications.