Evaluation context for xf:setindex

Hi All,

maybe I'm missing something, but I can't find a statement about what 
exactly is supposed to be the evaluation context for the index attribute 
of xf:setindex:

Is it a) the binding context established by the enclosing element of 
element xf:setindex, or is it b) the binding context of element 
xf:repeat referenced by the repeat attribute of element xf:setindex ?

I'd prefer a) since it's consistent with other actions rules. Any opinions ?

Regards,
Uli.
-- 
Ulrich Nicolas Lissé