<<< native [ EIdentifier "B" , EUnderover False (ESymbol Op "\8594") (EIdentifier "f") (EGrouped []) , EIdentifier "A" , EUnderover False (ESymbol Op "\8592") (EIdentifier "f") (EGrouped []) , EIdentifier "C" ] >>> eqn B -> from f to {""} A <- from f to {""} C