1 files changed, 24 insertions, 0 deletions

diff --git a/src/Data/JLD/Model/ListObject.hs b/src/Data/JLD/Model/ListObject.hs
new file mode 100644
index 0000000..8dda349
--- /dev/null
+++ b/src/Data/JLD/Model/ListObject.hs
@@ -0,0 +1,24 @@
+module Data.JLD.Model.ListObject (isListObject, isNotListObject, toListObject) where
+
+import Data.JLD.Prelude
+
+import Data.JLD.Model.Keyword (Keyword (..))
+
+import Data.Aeson (Value (..))
+import Data.Aeson.KeyMap qualified as KM
+import Data.Vector qualified as V
+
+isListObject :: Value -> Bool
+isListObject (Object o) =
+    KM.member (show KeywordList) o
+        && ( KM.size o == 1
+                || (KM.size o == 2 && KM.member (show KeywordIndex) o)
+           )
+isListObject _ = False
+
+isNotListObject :: Value -> Bool
+isNotListObject = isListObject .> not
+
+toListObject :: Value -> Value
+toListObject value@(Array _) = Object <| KM.singleton (show KeywordList) value
+toListObject value = Object <| KM.singleton (show KeywordList) (Array <| V.singleton value)