-@tyConArgVrcs_maybe@ gives a list of (occPos,occNeg) flags, one for
-each tyvar, if available. See @calcAlgTyConArgVrcs@ for how this is
-actually computed (in another file).
-
-\begin{code}
-tyConArgVrcs :: TyCon -> ArgVrcs
-tyConArgVrcs (FunTyCon {}) = [(False,True),(True,False)]
-tyConArgVrcs (AlgTyCon {argVrcs = oi}) = oi
-tyConArgVrcs (PrimTyCon {argVrcs = oi}) = oi
-tyConArgVrcs (TupleTyCon {tyConArity = arity}) = (replicate arity (True,False))
-tyConArgVrcs (SynTyCon {argVrcs = oi}) = oi
-\end{code}
-