cvt (InfixE Nothing s Nothing ) = cvt s -- Can I indicate this is an infix thing?
cvt (SigE e t) = do { e' <- cvtl e; t' <- cvtType t
cvt (InfixE Nothing s Nothing ) = cvt s -- Can I indicate this is an infix thing?
cvt (SigE e t) = do { e' <- cvtl e; t' <- cvtType t