Mixing r2l and l2r scripts in a path

[Kent Karlsson]

Patrik Fältström (or Patrik Faeltstroem or Patrik F{ltstr|m) wrote:
> I posted the example I tried to show during the wg meeting 
> today on my blog. Please have a look at
> 
> http://stupid.domain.name/node/681

One should note that the diplay you show in your example uses
a paragraph bidi level of 0 (LTR paragraph). The display will
be different if the paragraph bidi level is 1 (RTL paragraph),
in which case the line starts at the right side of the line.

In a "path name" (and similar) one ordinarily sees the / as a
field separator, similarly for the . in domain names. However,
that is not how the bidi algorithm treats / or other potential
graphical field separators. It treats / (., :, etc.) as appropriate
for running text. Only CHARACTER TABULATION and, as it happens,
the control character INFORMATION SEPARATOR ONE, are treated as
field separators by the bidi algorithm, forcing LTR display of
the fields (but not the content of the fields) for an LTR paragraph
and forcing RTL display of the fields (but not the content of the
fields) for an RTL paragraph. (Not that I have often seen this
correctly implemented; much more often not properly implemented.)

So even with the restrictions in idnabis-bidi, the "fields" of
a domain name (and similarly for a path name as in your example)
will not be displayed in the paragraph direction (unless one
substitutes . with <IS1, ., IS1> in the domain name, and
similarly for / in path names, just before doing bidi processing
in the display processing; something I don't think is expected).
The restrictions will only remove the ambiguities in reading the
displayed domain name (knowing the directionality in which the
name is displayed, and being aware of bidi script display) that
may arise without those restrictions.

	/kent k


> -----Original Message-----
> From: idna-update-bounces at alvestrand.no 
> [mailto:idna-update-bounces at alvestrand.no] On Behalf Of 
> Patrik Fältström
> Sent: Monday, July 28, 2008 6:41 PM
> To: idna-update at alvestrand.no
> Subject: Mixing r2l and l2r scripts in a path
> 
> I posted the example I tried to show during the wg meeting 
> today on my  
> blog. Please have a look at
> 
> http://stupid.domain.name/node/681
> 
>     Patrik
> 
> _______________________________________________
> Idna-update mailing list
> Idna-update at alvestrand.no
> http://www.alvestrand.no/mailman/listinfo/idna-update
>