On Fri, Mar 14, 2014 at 11:58 AM, Alessio Stalla alessiostalla@gmail.comwrote:
At the top level, PROGN is treated as if each contained expression appeared at the top level. So generally wrapping a PROGN around the result is precisely what you need to do.
However, since I see an IN-PACKAGE form in your example... beware that that IN-PACKAGE form will NOT affect the following DEFUN, because the symbols in it will have been read long before the IN-PACKAGE is executed.
Yikes, I read too fast, did not see the in-package. Well, the "doing something else wrong" suggestion stands. :) But this works in Allegro CL:
(defmacro go4it (n) `(progn (in-package :mcna.db) (defun forty2 () ,n)))
(go4it 42)
(print (forty2))
I put this in a source file in a library source with a different package, in a Lisp session where :mcna.db was already a Lisp package.
I do find supplying an in-package form in a macro expansion alarming, though. I never use it, but would use-package work?
-hp
On Fri, Mar 14, 2014 at 4:45 PM, Paul Tarvydas paultarvydas@gmail.comwrote:
What is the best way to write a macro that returns more than one form to the top level? E.g.
(in-package :xxx) (defun ...)
I've been wrapping a progn around the result, but LW doesn't like it very much, and SBCL seems to hate it.
Thanks pt