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Re: Fresh syntax

This page is part of the web mail archives of SRFI 77 from before July 7th, 2015. The new archives for SRFI 77 contain all messages, not just those from before July 7th, 2015.


dyb@xxxxxxxxxxxxxx writes:

* The SRFI 72 model would be an incompatible change affecting a large
corpus of syntax-case macros written over the dozen or so years since
   syntax-case was introduced.  Furthermore, identifying the places
   affected by the change would be nontrivial.

This argument contradicts the statement in the June 2006 R6RS status report:

With respect to future viability, we operate under the assumption that many more Scheme programs will be written in the future than exist in the present, so the future programs are those with which we must be most concerned.

I noticed this for two reasons.

The first was that the authors of SRFI-77 don't seem to have any problem removing quotient and remainder, which match hardware operations on nearly every known architecture, and which I'm sure many, many more programs use than use syntax-case. If there is a hardware architecture that has single instructions for the proposed div or mod on small integers, I don't know what it is.

The second is that I have not not yet written a syntax-case macro, and I don't want to be saddled with an error-prone for complex macro systems, but "benefits macros that are self-contained", standardization of syntax-case. It is still painful to think of years of debugging subtle errors in fixnum and flonum declarations in Gambit, for example, without having a "build in tests to tell me when I've lied to the compiler" declaration.