@@ -187,10 +187,10 @@ Of the various types, there are three atomic types, ~<number>~, ~<variable>~ and
(declare (ignore expression))
t)
- (defmethod subsitute-expression (expression with (in <atomic>))
- (if (eqal expression in)
- with
- in))
+ (defmethod substitute-expression (replace replacement (expression <atomic>))
+ (if (eqal expression replace)
+ replacement
+ expression))
#+END_SRC
*** DONE Numbers