mynthcdr has the same signature of the built in nthcdr function
() and nil are the same value
600 is the limit to the number of calls in a tail recursive function
nth returns the nth element in a list
Another implementation of nth, using nthcdr
and so does setcdr
my-zap-to-char kills up to (and including) Nth occurrence of the character char from point
explicit is better than implicit: the BOUND parameter in search-forward is (point-max)
refactoring: goto-nth-occurrence-of-char
playing with dynamic and lexical binding. Nested bindings