[XeTeX] xunicode.sty bug

[Ross Moore]

Hi Jonathan, Ralf, Will, Toralf, and others.


On 18/07/2006, at 8:36 PM, Jonathan Kew wrote:

>> Jonathan Kew <jonathan_kew at sil.org> writes:
>>
>>>> Ux00AD  soft hyphen
>>>
>>> This is the Unicode character that means essentially the same as
>>> TeX's "\-". A non-printing layout control that indicates a potential
>>> break point, not a visible character in its own right. If the line
>>> actually breaks there, the appropriate visible manifestation is
>>> script/language-dependent; a common default would be to insert U 
>>> +2010
>>> before the break, but this is not universally correct.

If I understand correctly, \- is primitive in TeX which is basically
a shorthand for  \discretionary{-}{}{} resulting in use or otherwise
of the \hyphenchar for the current font.

Without changing this mechanism, it seems that having
     \hyphenchar=^^ad
would do the right thing, provided the font has a glyph there.
This is a matter for  fontspec  to determine, yes ?


I suppose the issue is really what happens to any hyphenations
when you select and copy a paragraph from a PDF prepared by XeTeX.
Is the U+00AD actually present within the Unicode string ?
Do you see the glyph or not when the result is pasted into a
text-editor ?


> In the case of xetex, I think a sensible default (to handle the
> situation where U+00AD occurs in the input text) would be to say:
>
>      \catcode"AD=\active
>      \let^^ad=\-

This seems to be the right implementation, when an author
has included ^^ad (by whatever means) within the source.

It seems to me that these assignments are completely standard,
so belong in  xetex.xfmt , rather than being added by a package.
I could put them into xunicode.sty , but really don't think that
it is appropriate. Agreed ?


>
> JK

Cheers,

	Ross

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Ross Moore                                         ross at maths.mq.edu.au
Mathematics Department                             office: E7A-419
Macquarie University                               tel: +61 +2 9850 8955
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