geometry.boundaryLength(...)
attr x = geometry.boundaryLength(...)
@StartRule
Lot --> primitiveQuad(6, 4)
extrude(geometry.boundaryLength * 0.3)
comp(f) { top: Roof | side: Wall }
Roof --> color(0.5, 0.25, 0.15)
Wall --> color(0.75, 0.72, 0.68)