foldl %Y nat %X nat F %Y %X Y nil Y foldl %U nat %Z nat G %U %Z V cons W P foldl %W nat %V nat G %W %V G V W P sum X1 foldl %G nat %F nat plus %G %F 0 X1 F nat nat nat Y nat G nat nat nat V nat W nat P natlist X1 natlist 0 nat cons nat natlist natlist foldl nat nat nat nat natlist nat nil natlist plus nat nat nat sum natlist nat FULL /tmp/tmpfile.afsm