[luatex] a question about the names \Umathcharnumdef etc

[Joseph Wright]

On 16/10/2015 09:35, jfbu wrote:
> 
> Le 16 oct. 2015 à 09:47, Ulrike Fischer <luatex at nililand.de> a écrit :
> 
>> Am Thu, 15 Oct 2015 18:18:58 +0100 schrieb David Carlisle:
>>
>>>> or perhaps \Umathcharnumdef was always ok ?
>>>
>>> yes, it was, the Umath... commands were always available with their
>>> basic luatex names and also prefixed luatex.
>>
>> That's not true. In a texlive 2012
>>
>> \documentclass{article}
>>
>> \begin{document}
>> \show\Umathcharnumdef
>> \show\luatexUmathcharnumdef
>> \end{document}
>>
>> gives
>>
>>> \Umathcharnumdef=undefined.
>> l.36 \show\Umathcharnumdef
>>
>> ?
>>> \luatexUmathcharnumdef=\Umathcharnumdef.
>> l.37 \show\luatexUmathcharnumdef
> 
> The file 
> /usr/local/texlive/2012/texmf-dist/tex/latex/latexconfig/lualatexiniconfig.tex
> says that 
>>   % etex and pdftex primitives are enabled without prefixing
>>   % as well as extented Unicode math primitives (see below)
>>
> 
> but as your test file shows this was not the case for \Umathcharnumdef
> (and also \Umathcodenum which I tested).

In older versions of LuaTeX, the \U... primitives were part of the
"luatex" list so were enabled with the \luatex... prefix. Those
primitives now live in a dedicated "umath" list so cn be enabled
separately from the other LuaTeX-specific ones.

> I recall now that mathastext prior to TeXLive 2013 did not use
> \luatexUmathcharnumdef because the right side of the assignment would have
> been \luatexUmathcodenum`\-\relax, but \luatexUmathcodenum back then
> did not always return a Unicode mathcode.

This is the issue with supporting older versions of a developing engine!
I'd suggest you strongly consider saying that only newer releases are
supported. (The LaTeX team are considering much the same for
expl3/LuaTeX support.)

Joseph