Re: Compiling a recursive macro

[Douglas Lewan]

On 6/11/20 4:57 PM, Stefan Monnier wrote:
> > That suggests to me that you can't compile any recursive macro.
> Depends what you mean by "recursive macro".
> What this prevents is to use a macro inside the definition of a macro.
>
> Most cases of "recursive macros" instead just returns code which
> itself uses that macro.  In that case, there's no real recursion: the
> macro just returns a list which happens to include a symbol which has
> the same name as the macro.  And then the macro-expander will end up
> calling that macro back when it gets to macro-expanding that chunk
> of code.
> This works just fine (and may inf-loop, of course).

It did work when not compiled. However, when compiling I got a 
max-depth-exceeded error. (Forgive the paraphrasing, I'm now running a 
new instance of emacs.

And, if anyone cares, I did find a work-around for the macro in 
question. It had the following structure:

(defmacro mmm ()
    (cond ((at-root-p)
           do  tree-wide stuff)
          (t
           (with-current-buffer root (mmm)))

Since there is never more than one level of recursion, I defined another 
macro to do the tree-wide stuff first and then call that from mmm.


--
,Doug
d.lewan2000@gmail.com
(908) 720 7908

If this is what winning looks like, I'd hate to see what losing is.