foldr %Y nat %X nat F %Y %X Y nil Y foldr %U nat %Z nat G %U %Z V cons W P G W foldr %W nat %V nat G %W %V V P length X1 foldr %G nat %F nat s %F 0 X1 F nat nat nat Y nat G nat nat nat V nat W nat P list X1 list 0 nat cons nat list list foldr nat nat nat nat list nat length list nat nil list s nat nat FULL /tmp/tmpfile.afsm