I am not able to use #1#2 arguments... Don't know what is going on.
thank you for your help

ciro
---------------------------------


Case 1)  
\setuphead[chapter][command=\MyChapterCommand]
\def\MyChapterCommand{}

\starttext
\chapter{first chapter}
\stoptext

output: no error message, pdf file produced. Everything as expected.

Case 2)
\setuphead[chapter][command=\MyChapterCommand]
\def\MyChapterCommand#1#2{{#1} : {#2}}

\starttext
\chapter{first chapter}
\stoptext

output:
.
.
.
fonts           > 'fallback modern rm 12pt' is loaded
structure       > sectioning > chapter @ level 2 : 0.1 -> first chapter
! Argument of \MyChapterCommand has an extra }.

system          > tex > error on line 6 in file /home/ciro/Desktop/TGM_SpanishTranslation/test2.tex: Argument of  ...

1     \setuphead[chapter][command=\MyChapterCommand]
2     %\def\MyChapterCommand{}
3     \def\MyChapterCommand#1#2{{#1} : {#2}
4     }
5     \starttext
6 >>  \chapter{first chapter}
7     \stoptext
8