[XeTeX] additional beginL endL nodes in math

[David Carlisle]

On 16 April 2015 at 01:21, Vafa Khalighi <glkvafa at gmail.com> wrote:
> I also support Khaled's changes to xetex; I only tested it few months ago
> and if the issues I reported are fixed now, then it is good. And since when
> LaTeX has a package/ or test files that uses \beginL \endL? All I remember
> is that there are only babel's rlbabel.def file and then arabicore package
> but these packages themselves contain  bugs (irrelevant to xetex). bidi is
> the only big package that uses e-tex bidirectional algorithm for right to
> left typesetting. With the new changes of xetex, bidi package needs to be
> written from scrtach but I have no complain against it; the news that the
> \special and other issues fixed in xetex makes me so happy that I will not
> complain about changes. I am grateful to Khaled for fixing them.
>
>

The problem is not so much documents or packages that use \beginL
rather those that do not.

The document I posted earlier does not use any features of xetex or even etex
and is usable with original classic tex82.

in tex, etex, pdftex, luatex  and xetex 2014 it typesets 700
in xetex 2015 it typesets 0.

Whichever way you look at it this is a big incompatibility and I
started the thread to gain
a better understanding of why the change was made.

So now I see that while it's not ideal, given the resources and the
seriousness of the
bugs that were being fixed, it's an understandable decision to go with
this route at the
present time. It causes us some problems in latex maintenance, but we'll cope.

David