ref: c050cd0d60c6473ee4c65efc9b3459fbfa011335 dir: /tests/Deriving.ref/
True False False True False True True True False True False A 'a' B False C 'a' 1 D A (A 'a') R{x='a',y=10} R{x=R{x='b',y=11},y=10} Alt [True]