[r6rs-discuss] Why can ... and _ not be literals?

From: AndrevanTonder <andre>
Date: Tue, 26 Jun 2007 21:12:46 -0400 (EDT)

On Tue, 26 Jun 2007, David Van Horn wrote:

> On 6/25/07, AndrevanTonder <andre at het.brown.edu> wrote:
>> There is in fact a trivial solution to porting legacy macros
>> using underscore. Simply put them in a library where you use
>>
>> (import (except (r6rs base) _))
>
> Isn't this a syntax violation? This excludes `_' from (meta 0),
> implicitly, but (r6rs base) provides `_' only at (meta 1).

No - it excludes _ from all meta-levels at which (r6rs base) would have
otherwise provided it, in this case only 1 (and therefore all of them).

Cheers
Andre
Received on Tue Jun 26 2007 - 21:12:46 UTC