Jean-Marc Lasgouttes wrote:
> From what I understand the problem is with passing some option to
> fontspec.sty, right? Could you give me an executive summary? Is the
> problem that luatex will not work at all when fontspec is too old? Can't
> check the luatex version to assert this?
The problem here is summarized in BufferParams:
// "Mapping=tex-text" and "Ligatures=TeX" are equivalent.
// However, until v.2 (2010/07/11) fontspec only knew
// Mapping=tex-text (for XeTeX only); then "Ligatures=TeX"
// was introduced for both XeTeX and LuaTeX (LuaTeX
// didn't understand "Mapping=tex-text", while XeTeX
// understood both. With most recent versions, both
// variants are understood by both engines. However,
// we want to provide support for at least TeXLive 2009.
That means, we should (ideally) disable LuaTeX support if fontspec is older
than 2010/07/11. The rest (using "Ligatures=TeX" for both XeTeX and LuaTeX
after 2010/07/11) is rather cosmetics.
I think that the current solution is OK. However, a check for specific package
versions would generally be useful.
Jürgen
