@base1=rc([0,0,0],[7,7,7])
@base2=rc([8,0,0],[15,7,7])
@extension=rc([16,0,0],[23,7,7])

@level1=base1+base2
@level2=level1+extension
@final=(level1+level2)+extension

#level1:description="Simple union"
#level2:description="Extended union"
#final:description="Complex nested expression"
#final:components=["base1","base2","extension"]
