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

This page is part of the web mail archives of SRFI 91 from before July 7th, 2015. The new archives for SRFI 91 contain all messages, not just those from before July 7th, 2015.

Marc Feeley scripsit:

> >The SRFI should explicitly permit implementation-dependent encodings
> >and eol-encodings.  (XML 1.1 allows CR, LF, CR/LF, NEL=U+0085, and
> >LS=U+2028.)
> What do you mean by "explicitly permit"?  In general an  
> implementation can extend an API any way it wishes!  The spec is only  
> a requirement.

Well, the informal BNF could be read as requiring that a conforming
implementation accept these values and no others.  Two sentences of
the form "Other values may be accepted by conforming implementations"
wouldn't hurt.

> It only depends on u8vectors which are common in SRFI 4 and SRFI 66.   
> SRFI 66 has things that SRFI 4 does not have, and vice versa.  I  
> could add a reference to SRFI 66 though.

Fair enough.

> 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.

In my last lifetime,                            John Cowan
I believed in reincarnation;                    http://www.ccil.org/~cowan
in this lifetime,                               cowan@ccil.org
I don't.  --Thiagi