| C.Cast (te,ty) -> C.Cast (unshare te, unshare ty)
| C.Prod (n,s,t) -> C.Prod (n, unshare s, unshare t)
| C.Lambda (n,s,t) -> C.Lambda (n, unshare s, unshare t)
| C.Cast (te,ty) -> C.Cast (unshare te, unshare ty)
| C.Prod (n,s,t) -> C.Prod (n, unshare s, unshare t)
| C.Lambda (n,s,t) -> C.Lambda (n, unshare s, unshare t)