diff options
Diffstat (limited to 'compiler/types/TyCon.hs')
| -rw-r--r-- | compiler/types/TyCon.hs | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/compiler/types/TyCon.hs b/compiler/types/TyCon.hs index 8e0175a6cf..c3723c4661 100644 --- a/compiler/types/TyCon.hs +++ b/compiler/types/TyCon.hs @@ -42,6 +42,7 @@ module TyCon( promotableTyCon_maybe, promoteTyCon, isDataTyCon, isProductTyCon, isDataProductTyCon_maybe, + isEmptyDataTyCon, isEnumerationTyCon, isNewTyCon, isAbstractTyCon, isFamilyTyCon, isOpenFamilyTyCon, @@ -1286,6 +1287,15 @@ isDataProductTyCon_maybe (TupleTyCon { dataCon = con }) = Just con isDataProductTyCon_maybe _ = Nothing +-- | True of datatypes with no constructors +isEmptyDataTyCon :: TyCon -> Bool +isEmptyDataTyCon tc + | AlgTyCon {algTcRhs = rhs} <- tc + , [] <- data_cons rhs + = True + | otherwise + = False + -- | Is this a 'TyCon' representing a regular H98 type synonym (@type@)? isTypeSynonymTyCon :: TyCon -> Bool isTypeSynonymTyCon (SynonymTyCon {}) = True |