expr_fvs :: CoreExpr -> FV
expr_fvs (Type ty) fv_cand in_scope acc =
  tyCoFVsOfType ty fv_cand in_scope acc
expr_fvs :: CoreExpr -> FV
expr_fvs (Type ty) fv_cand in_scope acc =
  tyCoFVsOfType ty fv_cand in_scope acc
expr_fvs (Type ty) fv_cand in_scope acc =
  tyCoFVsOfType ty fv_cand in_scope acc