[Audacity-nyquist] Push and macros

[David R. S. <dav...@sh...>]

In line with my previous question about pushing a value onto the
end (rather than the start) of a list, I took a look at the def for
push:

(defmacro push (val lis) `(setf ,lis (cons ,val ,lis)))

and wrote a macro I call pushlast, which appears to work:

(defmacro pushlast (val lis) `(setf ,lis (reverse (cons ,val
(reverse ,lis)))))

Apart from the fact it produces the desired result:

> (setf mylist (list 1 2 3))

(1 2 3)

> (pushlast 4 mylist)

(1 2 3 4)

is there anything wrong with this? This is my first macro-writing
attempt, I haven't used the comma or accent symbols previously, but
followed the pattern in push.

Thanks

David