[NTG-context] catcode change in macros

Hi, I make in a module the comment sign a simple letter to pass number formats to a lua function and want to know if should use another (better) way to change the catodes. \def\????ax{@@@@ax} \bgroup \catcode`\%=11 \catcode`\:=14 \gdef\setupaxis {\catcode`\%=11 \catcode`\:=14 \dodoubleargument\dosetupaxis} \gdef\dosetupaxis[#1][#2]: {\catcode`\%=11 \catcode`\:=14 \def\docommand##1{\getparameters[\????ax##1][#2]}: \catcode`\%=14 \catcode`\:=12 \processcommalist[#1]\docommand} \egroup \setupaxis [\c!x,\c!y] [\c!format=%d] Regards, Wolfgang