Hi. Reading at mult-aux.mkxl, I've seen command handlers define, among others,  \installparameterhashhandler, However, in files such as those related with symbol management, only \installparameterhandler and \installsetuphandler are. When writing basic modules, sometimes only the "raw" macros above are actually needed. So, what are "parameterset", "hashhander", "rootparameterhandler", etc. for? Where would they ease module writing? Thank you a lot and sorry for the long question. The ones you mention are the lowest level ones and mechanisms that use

On 11/9/2021 8:01 PM, Jairo A. del Rio via ntg-context wrote: them are oned that don't really have much to manage (like symbols and languages and fonts and so, these are core mechanisms on their own and need additional interfaces. There's also the matter of performance: anything key/value driven can have a performance hit so the more one wraps the worse it can get. (The mkii and mkiv/lmtx methods differe fundamentally, where in principle the mkii approach is faster but in practice mkiv/lmtx works out better. A typical case where usage in the end determines performance more than the implementation.) For modules: don't go too low level. Not all helpers in modules like mult-aux are meant for usage outside well known situations. Just like some low level helpers in syst-aux stay around for compatibility. In fact, one of the ideas behind luametatex/lmtx is to get rid of "complex" middle layers where the language itself can do it, so: \protected\def\foo[#1]{\dosingleempty\dofoo} \def\dofoo[#1]{...} in mkii/mkiv can now be: \tolerant\protected\def\foo[#1]{...} (1) less code (2) somewhat faster (3) looks nicer (for me much is about looks) but I guess that you already know that, Hans ----------------------------------------------------------------- Hans Hagen | PRAGMA ADE Ridderstraat 27 | 8061 GH Hasselt | The Netherlands tel: 038 477 53 69 | www.pragma-ade.nl | www.pragma-pod.nl -----------------------------------------------------------------