Le 01/01/2011 20:32, Joseph Wright a écrit :
>
> On 01/01/2011 18:17, TeXWorld wrote:
>> Hello,
>>
>> What engines LaTeX3 is (and will be) designed to work with ? Like
>> LaTeX2e it will work with TeX, PDFTeX, XeTeX, LuaTeX, (Aleph...???), or
>> with a more limited list such as LuaTeX and XeTeX ? I'd like to know if
>> a decision has been taken and whether it has, I'd like to know why such
>> a decision.
>>
>> Thank you.
>>
>> Jack
>>
>
> Hello Jack,
>
> I think a bit of history is needed here. At first, the only primitives 
> that expl3 *required* were those from TeX82 (Knuth's TeX). Some years 
> ago now, it was decied to require the e-TeX extensions. These allow a 
> number of functions to be carried out which are difficult or 
> impossible otherwise. More recently, we have added \pdfstrcmp to the 
> list of required primitives. This primitive allows expandable 
> string-based comparisons, which are important for some low-level expl3 
> functions. So the requirement at present is a TeX engine which 
> includes the e-TeX extensions and the functionality of \pdfstrcmp. 
> This means the following engines should work:
>
>  - pdfTeX v1.30 or later
>  - XeTeX v0.9994 or later
>  - LuaTeX v0.40 or later
>
> As LaTeX3 is far from ready, this may change in the future. However, 
> the team have always been relatively cautious about engine 
> requirements, and I expect that the above will remain as the minimum 
> engine list for some time to come. (With LuaTeX, I'd strongly 
> recommend a newer engine, given the pace of development of the binary. 
> I'd *suggest* at least 0.60.)
>
> Joseph Wright
>
>
Thank you Joseph.

Have the LaTeX3 team ever thought of making LaTeX3 only work with LuaTeX 
and XeTeX ? Why ? To integrate directly into the format fontspec 
functionnalities for instance.