[r6rs-discuss] Why Unicode matters

[Alan Watson]

Hi Tom,

I also congratulate the R6RS editors and John Cowan on producing an  
good specification for Unicode in Scheme.

> 1) Should the standard allow a conforming implementation
> to support only a smaller character set in source texts?
> (I say "yes" for pragmatic reasons - I don't need all
> of Unicode or all the Scheme libraries in the world for
> a tiny embedded system, for example.)

As I'm sure you know, twenty years ago C solved a similar problem by  
defining "hosted" and "free-standing" implementations. Hosted  
implementations had to support the entire language and the entire  
library. Free-standing implementations had to support the entire  
language but only a trivial subset of the library (<float.h>,  
<limits.h>, <stdarg.h>, and <stddef.h>).

It might well be possible to define such a "free-standing" subset of  
R6RS Scheme, although the pervasive influence of Unicode on the  
lexical grammar might be a problem.

Regards,

Alan
-- 
Alan Watson
http://www.alan-watson.org/