On 2013–04–15 Hans Hagen wrote:

> As follow up on the combinations tread I made this:
> 
> …
> 
> A relative simple extension but probably useful.

How about making the first bracket pair optional if key-value
options are passed? This would allow for the following syntax:

\starttext

%% works:
%% \startcombination [][nx=3, ny=1]

%% suggestion, fails at the moment
\startcombination [nx=3, ny=1]
  {a}{x}
  {b}{x}
  {c}{x}
\stopcombination

\stoptext

Marco