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Re: Update available-- possibly last before finalization

This page is part of the web mail archives of SRFI 57 from before July 7th, 2015. The new archives for SRFI 57 contain all messages, not just those from before July 7th, 2015.

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.