Re: Compiling a recursive macro

[Michael Heerdegen <michael_heerdegen@web.de>]

Douglas Lewan <d.lewan2000@gmail.com> writes:

> I managed to lose the last response to my original question, the one
> with the case_ macro. Here it is for reference:

BTW, if you didn't know: `macroexpand-1', `macroexpand' and
`macroexpand-all' are your fried when playing with macros.

BTW2, a small problem with your posted version is that it adds one `let'
binding per branch, but only the outermost is needed:

(macroexpand-all '(case_ x ((1 2) t) (3 nil)))

==>

(let ((#1=#:g772 x))
  (if (member #1# '(1 2))
      t
    (let ((#2=#:g773 #1#))      ;; <--- here
      (if (member #2# '3)
          nil nil))))

That is not harmful but a bit inelegant and inefficient.


Michael.