Re: Update available-- possibly last before finalization Felix Winkelmann 10 Dec 2004 06:18 UTC

Andre van Tonder wrote:
> On Thu, 9 Dec 2004, Felix Winkelmann wrote:
>
>> Hm... Non-generative record definitions would be nice.
>
>
> Yes, although the particular Chez Scheme specification would be
> difficult to implement portably.
>
> One thing I like about the current specification is that it can be
> implemented as a macro layer on top of SRFI-9, as the reference
> implementation indeed does, without having to manipulate the innards, in
> particular the record type descriptors, of SRFI-9.  Because of this
> philosophy, it can be used on any Scheme implementation that has SRFI-9,
> and it can also be easily adapted to Schemes that have their own
> efficient native records.  Including nongenerativity would make this
> impossible, and for this reason is perhaps better left to a future SRFI.
>

 From what my experiments show the current SRFI-57 reference implementation
does *not* work on systems that provide a non-generative SRFI-9, or non-
generative native records.
I haven't understood your code well enough to say whether it's too difficult
to handle generative and non-generatve records, but if you say so I
accept that. It would just be a handy thing to have. Having only generative
records makes it just impossible to use the constructor macros in a
separate compilation model, AFAICT.

cheers,
felix