| C.Cast (v,t) -> C.Cast (aux v, aux t)
| C.Prod (b,s,t) -> C.Prod (b,aux s, aux t)
| C.Lambda (b,s,t) -> C.Lambda (b,aux s, aux t)
| C.Cast (v,t) -> C.Cast (aux v, aux t)
| C.Prod (b,s,t) -> C.Prod (b,aux s, aux t)
| C.Lambda (b,s,t) -> C.Lambda (b,aux s, aux t)