Re: [Chicken-users] 32 bit integers?

[Kon Lovett]

On May 23, 2007, at 6:33 AM, Dan Muresan wrote:

> > The SRFI-60 egg, per the SRFI document, exports bitwise-* & and  
> > arithmetic-shift, which override the definitions in the library  
> > unit. It probably should at least rename them before the override.  
> > I will do this & release an update SRFI-60. (Personally I don't  
> > think the aliases are a good idea but that is the SRFI.)
>
> The strictest interpretation of the aliasing requirement that I can  
> concieve of is that
>
> (eq? bitwise-ior logior)
>
> returns true. I don't think the SRFI mandates the reference  
> implementation to be used. Therefore, you could simply alias logior  
> to mean bitwise-ior etc.
>
> This would solve the bug, right?

Yes. What I did was a Q&D placeholder. W/O a real review of the  
semantics of SRFI-60 I didn't feel comfortable w/ the above.

W/ the numbers egg the reference implementation will work w/ bignums.  
(Interesting given that GMP uses sign-magnitude & not 2s-complement.)  
While the document speaks of fixnums, it uses the term  
interchangeably with integer.

Maybe the log* operations could have a broader definition of  
'integer' than the bitwise-* operations.

But, it might be best to be true to the spirit of the SRFI. In any  
case, the bit fiddling/logic operations on bignums should be done by  
GMP so a SRFI-60 extension for the numbers egg is a good idea.

Best Wishes,
Kon

> -- Dan