RScheme has various #foo, deriving from Dylan which apparently dropped the "!".

On 4/11/06, Marc Feeley <xxxxxx@iro.umontreal.ca> wrote:
> On 11-Apr-06, at 4:51 PM, Per Bothner wrote:
>
> > Marc Feeley wrote:
> >> Some Scheme systems still use the #!foo syntax for some objects
> >> (Gambit and Chez Scheme use #!eof to denote the end-of-file object).
> >
> > So does Kawa, which also has:
> > #!void - same as (values):  The result of "void expressions".
> > #!null - Java null.
> > #!default and #!undefined - used mainly internally.
> > --
> >       --Per Bothner
> > xxxxxx@bothner.com   http://per.bothner.com/
>
> And here's the complete set for Gambit:
>
>   #!eof         end-of-file
>   #!void        void object
>   #!unbound     unbound variable
>   #!unbound2    unbound variable
>   #!optional
>   #!rest
>   #!key
>
> Are there other Scheme systems that use the #!foo syntax?
>
> Marc
>
>

--
-- Donovan