Sylvain Hubert schrieb am 04.11.2020 um 22:10:
On Wed, 4 Nov 2020 at 21:32, Wolfgang Schuster <wolfgang.schuster.lists@gmail.com> wrote:
4. it performance issues and leads to a noticeable performance drop.

This sounds a bit surprising, since intuitively it takes no less effort to deal with the registered key than to determine that a key is not registered.

There was never a real test for the performance but when you enable the checker in the example below (which works only with LuaTeX) the second list is slower.

% engine=luatex

\starttext

\testfeatureonce{10000}{\getcheckedparameters[test][xx][a=b,c= d, e = f]}

\enablecheckparameters

\testfeatureonce{10000}{\getcheckedparameters[test][xx][a=b,c= d, e = f]}

\stoptext

Wolfgang