let map (c1, v1) (c2, v2) =
let m1, m2 = {m1 with e = c1; s = []}, {m2 with e = c2; s = []} in
ac {st with Y.si = false} m1 v1 m2 v2
let map (c1, v1) (c2, v2) =
let m1, m2 = {m1 with e = c1; s = []}, {m2 with e = c2; s = []} in
ac {st with Y.si = false} m1 v1 m2 v2