qualif Zog(v:a) : (10 <= v) qualif Bog(v:a, x:a) : (x <= v) bind 0 a : {v: int | $k0[zogbert := pikachu] } constraint: env [ ] lhs {v : int | v = 10} rhs {v : int | $k0} id 1 tag [] constraint: env [ ] lhs {v : int | v = 20} rhs {v : int | $k0} id 2 tag [] constraint: env [ 0 ] lhs {v : int | v = a} rhs {v : int | 10 <= v} id 3 tag [] wf: env [ ] reft {v: int | $k0}