Also, have a look at
http://www.ctan.org/tex-archive/graphics/metapost/contrib/macros/metaobj
It seems that it has the same power of XY-pic .
--
luigi
----------------------------------------------------------------
If your question is of interest to others as well, please add an entry to the Wiki!
maillist :
ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context
webpage : http://www.pragma-ade.nl /
http://tex.aanhet.net
archive : https://foundry.supelec.fr/projects/contextrev/
wiki : http://contextgarden.net