Re: [mew-int 01596] Re: windows 1252

[Kenichi Handa]

In article <address@hidden>, "Eli Zaretskii" <address@hidden> writes:
>>  I think Dave is correct because CTEXT spec has this
>>  paragraph.
>>  
>>      Extended segments are not to be used for any character set
>>      encoding that can be constructed from a GL/GR pair of
>>      approved standard encodings. For example, it is incorrect to
>>      use an extended segment for any of the ISO 8859 family of
>>      encodings.

> For the record, when I worked on this code, I added the ISO 8859
> charsets mentioned above because the then official version of the
> CTEXT spec did not include them in the list of approved standard
> encodings.  So, as far as that CTEXT spec was concerned, these
> charsets were not members of the ISO 8859 family.

Hmmm, I didn't understand the above paragraph as you, but it
seems that you are correct.  Dave, what do you think?

FYI, I found this section in the spec.

------------------------------------------------------------
10.  Extensions

There is no absolute requirement for a parser to deal with
anything but the particular encoding syntax defined in this
specification.  However, it is possible that Compound Text
may be extended in the future, and as such it may be desir-
able to construct the parser to handle 2022/6429 syntax more
generally.

There are two general formats covering all control sequences
that are expected to appear in extensions:

01/11 {I} F

     For this format, I is always in the range 02/00 to
     02/15, and F is always in the range 03/00 to 07/14.

[...]
If extensions to this specification are defined in the
future, then any string incorporating instances of such
extensions must start with one of the following control
sequences:

     01/11 02/03 V 03/00   ignoring extensions is OK
     01/11 02/03 V 03/01   ignoring extensions is not OK
[...]
------------------------------------------------------------

So, designating ISO-8859-15 by ESC - b (i.e. 01/11 {I} F)
without any of the last two ESC sequences explicitly
violates CTEXT even if CTEXT is exteneded in the future.

---
Ken'ichi HANDA
address@hidden