Test regression in rtest_trig with cmucl



On 7/19/12 5:50 PM, Barton Willis wrote:
> The intent of
>  
>     (setq l ($expand l))
>     (cons l l))
> 
> is to properly return (cons 0 0) or (cons 0.0 0.0), or ... Since 0 * 0.0
> --> 0,
> 
>     (setq l (mul 0 l))
>     (cons l l)
> 
> doesn't work. Or we could say uncle and return (cons 0 0)--that would be
> non-terrible.

How about calling ($rectform ($expand l))?  And then checking that a
zero is returned and if it's not, we produce an error.  The error is not
great, but at least it prevents us from erroneously returning a form
that should be zero but isn't.

Ray