Replace an item in a list in Common Lisp?

Question

I have a list of things (I\'ll call it L), an index(N) and a new thing(NEW). If I want to replace the thing in L at N with NEW, what is the best way to do this? Should I get the

Answer 1

Use [REPLACE][1] (I use X instead of your T as T is the true value in Lisp):

(replace L (list X) :start1 N)

[1]: http://www.lispworks.com/documentation/HyperSpec/Body/f_replac.htm REPLACE