\begin{code}
tyConDataCons :: TyCon -> [DataCon]
-tyConDataCons tycon = ASSERT2( not (null cons), ppr tycon ) cons
+tyConDataCons tycon = ASSERT2( not (null cons), ppr tycon )
+ ASSERT2( length cons == tyConFamilySize tycon, ppr tycon )
+ cons
where
cons = tyConDataConsIfAvailable tycon