(sorts a, b, c, d, x

sorts x < a; a, x < d

op o : a

op o : a -> b

op o2 : a ->? b

pred p : a

pred p : b

pred q : a

pred q : b,[ . forall v1, v2, v3: a . o = o,

. forall v1: a . o(v1) = o2(v1) ])

*** Hint 11.6, redeclared sort 'a'

*** Error 13.8, expecting two arguments of equal sort

*** Error 19.22, no operation with 0 arguments found for 'c'