Re: Suggested character set policy for the IETF

["Martin J. Duerst" <mduerst@ifi.unizh.ch>]

On Mon, 30 Jun 1997, Chris Newman wrote:

> On Fri, 27 Jun 1997, Martin J. Duerst wrote:
> > The first part of your definition, "mapping from octets to characters",
> > is very widely known and used. The second part of the definition, "related
> > presentation information", is new to me. Is this your own definition,
> > or where did you find it? What exactly does the term "presetation
> > information" mean for you? How do you assure that it means the same
> > thing for others?
> 
> The "related presentation information" is a missing portion of the
> definition.  There are things like CRLF, character directionality, Unicode
> joiner/no-joiners, etc. which effect presentation but are not "characters"
> in the traditional sense.

I see. The cases you mention are of course perfectly reasonable and
necessary. They are also subsumed under the term character in the
sense it is used in standards, which distinguishes (or should I say
distinguished?) between control characters and graphic characters.


> Suggestions for making it more precise would be helpful.  It'd be nice to
> get this right in the next revision of the MIME specification.

Well, in my oppinion, including something like "presentation" is
very dangerous. Soon you have people claiming that font information,
or whatever, has to be part of a "charset". Making the definition
more precise would be nice, but would probably take too much lines.
Just leaving it at "characters", and maybe refering to some of the
ISO work in that area for somebody who really wants to check, should
be okay.

Regards,	Martin.