[pstricks] Naive question

[Pedro Jorge Caridade]

Thanks Herbert. 
I am trying to learn the hard way: pick a package and try to understand
some instructions.
 
> defining it as an PSTricks object implies the reading of the
> optional parameters and the arrows
> >\def\ArrowPolygon at i%
> >{\@ifnextchar[{\ArrowPolygon@@ii}{\ArrowPolygon@@ii[]}}

OK! Could you explain me what are the differences in the case of
defining an object or not? If I need to pass arguments between brackets,
can I keep my instruction or its bad pstricks programming???

> \typeout{#2} otherwise youÄll get only the first digit

Stupid error!!!!!

> 
> \ArrowPolygon[linecolor=red,xunit=0.5,yunit=0.25,arrowscale=3](1,-1)(20,5)(10,15)

How does my macro understand these options? It is because I defined as
an pstricks object? I think I'm starting to understand this....

Sorry to bother you Herbert. By the way the solution for pcellipsearc
was ok! Another small question: when does your book be available in
English? 

Pedro