[Chicken-hackers] [PATCH] Fix cond behaviour of => with constant condition [Was: Re: [Chicken-users] Unbound => in cond statements]

[Peter Bex]

On Fri, Oct 17, 2014 at 07:44:27PM +0200, Michele La Monaca wrote:
> Hi,
> 
> curiously:
> 
> 
> (cond (1 => odd?))
> 
> Error: unbound variable: =>
> 
> while
> 
> 
> (cond (+ => procedure?))
> #t
> 
> The only difference I can spot is that 1 is self-evaluating while + is
> not. Anyhow, it doesn't look good to me.

Well-spotted!  This was due to an optimisation which rewrote
(cond (CONSTANT <whatever> ...) ...) to <whatever>, which is correct,
but it forgot to rewrite (cond (CONSTANT => <whatever>) ...) to
(<whatever> CONSTANT).

The attached patch fixes it.

Thanks for reporting this issue!

Cheers,
Peter
-- 
http://www.more-magic.net

0001-Fix-incorrect-optimization-in-cond-expansion.patch
Description: Text document