[luatex] a question about the names \Umathcharnumdef etc

[Joseph Wright]

On 15/10/2015 18:29, Joseph Wright wrote:
> On 15/10/2015 17:36, jfbu wrote:
>> Hi,
>>
>> as people reported problems with mathastext under lualatex I have become aware
>> that \luatexUmathcharnumdef etc... have been removed and \Umathcharnumdef etc...
>> must be used  instead.
>>
>> as I didn't find the info immediately I am asking here: how should I test
>> (version number, date etc...)
>> when one should use \luatexUmathcharnumdef and
>> when on should use \Umathcharnumdef ?
>>
>> or perhaps \Umathcharnumdef was always ok ?
>>
>> I would like to not break people's old installation thus I would be
>> glad to use \Umathcharnumdef  if I am told it works with all earlier lualatex
>>
>> best wishes
>>
>> Jean-François
> 
> Hello Jean-François,
> 
> The 'real' names of the primitives have always been just \Umath... For
> some time they've been enabled with the "luatex" prefix.. The LaTeX team
> have recently taken a more 'active' interest in directly supporting
> LuaTeX (and XeTeX) by modifying latex.ltx to 'know' about these engines.
> As part of that process, we've revised the approach to the newer
> primitives and dropped the prefix 'out of the box'.
> 
> For code that needs to work both with older (pre 2015/10/01) and newer
> (2015/10/01 onward) kernel releases, adding
> 
>     \directlua{
>       tex.enableprimitives("luatex", tex.extraprimitives("Umath"))
>     }
> 
> (for just the Umath set) will do the job. Alternatively, if the code in
> your package gets modified to drop the prefix then
> 
>     \directlua{
>       tex.enableprimitives("", tex.extraprimitives("Umath"))
>     }
> 
> will ensure that the 'natural' names are available with older kernel
> releases.
> 
> Regards,
> 
> Joseph

As I see David has noted, the \Umath... set have been available under
their 'natural' names since they were made available separately from
other LuaTeX additions. As such, any at all recent LuaLaTeX will have
them available directly.

Joseph