Hi,
On 05 May 2016, at 12:26, Hans Hagen
wrote: \appto, \preto, \apptocmd,... I think primitves would be much more faster and trustworthy.
Like Hans said: I think speed improvements are just wishful thinking. It is hard to beat the TeX language speed significantly from compiled C code if you are still doing more or less the same stuff the TeX language code would do. In (lua)TeX, useful speedups tend to come from doing a task differently, not from switching languages. Still planned for luatex is access to the macro replacement text as well as macro definition and possibly even alteration from the lua side of things. Altering macros from lua by using the lua token list interface would allow one to take macro parameters into account, and that would open up extra possibilities for sure. And it could improve reliability of such alterations, I assume. After some thinking, that sounds like a better way to go. In fact, thinking it over, I wonder whether we should not change \[e]toksapp and \[e]tokspre back to lua function calls? Best wishes, Taco