feature root "Product"
feature req "Required Feature"
feature altSub1 "Alternative Sub Feature1"
feature altSub2 "Alternative Sub Feature2"
feature opt "Optional Feature"
feature reqSub "Required Sub Feature"
feature optSub "Optional Sub Feature"
feature comb "Combined Feature"
feature sub1 "Sub Feature1"
feature sub2 "Sub Feature2"

root has req
root canHave opt
root has comb
opt has reqSub
opt canHave optSub

req hasOneOf [altSub1, altSub2]
comb hasSome [sub1, sub2]

sub1 requires optSub
altSub1 excludes sub2