\begin{code}
module TcUnify where
-import TcType ( TcTauType, BoxySigmaType, BoxyType )
+import TcType ( TcTauType )
import TcRnTypes( TcM )
import Coercion (CoercionI)
-- TcUnify and TcSimplify
unifyType :: TcTauType -> TcTauType -> TcM CoercionI
-boxyUnify :: BoxyType -> BoxyType -> TcM CoercionI
-zapToMonotype :: BoxySigmaType -> TcM TcTauType
\end{code}