Different bw compat of `cowValueModel`.

src/cow-value-model.js

@@ -74,14 +74,13 @@ export const deepCopyOnWrite = (...keyDescriptions) => {
 export const decow = deepCopyOnWrite;
 
 export const cowValueModel = (...keyDescriptions) => {
-    const keys = constructKeys(keyDescriptions);
-
     const GET_SENTINEL = {};
 
     return (obj, val = GET_SENTINEL) =>
-        val === GET_SENTINEL ?
-            deepGet(keys, obj) :
-            deepPut(keys, obj, val);
+        (val === GET_SENTINEL ?
+            deget(...keyDescriptions) :
+            decow(...keyDescriptions)(val))
+        (obj);
 };
 
 export const cowWorkshop = (keys, fn = x => x) => (obj, {result = obj, resultKeys = keys, diff} = {}) => {