set namespac object ns model facad namespac ns defin log lp log granular type statement log error illeg argument object ns namespac endif illeg argument except illeg argument object ns namespac init namespac set namespac ns diagram graph model gm diagram graph model graph model gm set home model ns init layer perspect lai layer perspect mutabl model facad ns gm diagram render rend diagram render singleton lai set graph node render rend lai set graph edg render rend set layer lai 