[NTG-context] how to get a commalist out of {}-brackets

Hi, I need to forward an embedded commalist to an subfunction. The problem: how can I get rid of the {}-brackets to access the embedded commalist? The functions looks like: \def\function#1[#2] {\getparameters[label][a=,b=,embedded=,#2] subfunction[\labelembedded] ...} \def\subfunction#1[#2] {\getparamters[label][a,c,#1] \labela % will answer with emptyness #2 % returns {a=,c=} ... but I need for the getparamteres a=,c= ...} to call the function: \function[a=etwas,b=ddd,embedded={a=nochWas,c=hope}]