Re: Why are byte ports "ports" as such?

[Marc Feeley <feeley@iro.umontreal.ca>]

On 14-Apr-06, at 9:57 AM, John Cowan wrote:

> > I'll add something in the preamble saying:
> >
> >    The tokens of the form ``foo:'' used in this document will be
> > called ``keywords''.
> >    On Scheme implementations supporting SRFI 88, these keywords
> > correspond to the
> >    keyword objects specified in that SRFI.  On Scheme
> > implementations which do not
> >    support SRFI 88, these keywords are symbols.
>
> Which is as much as to say that they need to be quoted on non-SRFI-88
> systems, as your followup notes.  This is always a safe strategy,
> since a quoted keyword evaluates to itself.
>
> Keywords are controversial (if nobody else, I am making controversy
> about them!), and this otherwise satisfactory SRFI should not, IMHO,
> depend on their presence.

I could add to the spec that

   On Scheme implementations that do not support SRFI 88, the  
variables ``direction:'',
   ``char-encoding:'', etc are defined to evaluate to the symbol of  
the same name.  That is

     (define direction: 'direction:)
     (define char-encoding: 'char-encoding:)
     ...

This way these ``keywords'' don't have to be quoted, regardless of  
support for SRFI 88.

I'll have to think about this some more but currently I don't see a  
problem with that.

Marc