make read-only types return in-memory data for write operations

Author: radarroark

src/xitdb/array_list.clj

@@ -18,11 +18,11 @@
   (count [_]
     (.count ral))
 
-  (cons [_ o]
-    (throw (UnsupportedOperationException. "XITDBArrayList is read-only")))
+  (cons [this o]
+    (cons o (common/materialize this)))
 
-  (empty [_]
-    (throw (UnsupportedOperationException. "XITDBArrayList is read-only")))
+  (empty [this]
+    [])
 
   (equiv [this other]
     (and (sequential? other)
@@ -33,7 +33,7 @@
 
   clojure.lang.IPersistentVector
   (assocN [this i val]
-    (throw (UnsupportedOperationException. "XITDBArrayList is read-only")))
+    (assoc (common/materialize this) i val))
 
   (length [this]
     (.count ral))

src/xitdb/hash_map.clj

@@ -35,21 +35,21 @@
         (clojure.lang.MapEntry. key v))))
 
   (assoc [this k v]
-    (throw (UnsupportedOperationException. "XITDBHashMap is read-only")))
+    (assoc (common/materialize this) k v))
 
   clojure.lang.IPersistentMap
-  (without [_ _]
-    (throw (UnsupportedOperationException. "XITDBHashMap is read-only")))
+  (without [this k]
+    (dissoc (common/materialize this) k))
 
   (count [this]
     (operations/map-item-count rhm))
 
   clojure.lang.IPersistentCollection
-  (cons [_ _]
-    (throw (UnsupportedOperationException. "XITDBHashMap is read-only")))
+  (cons [this o]
+    (cons o (common/materialize this)))
 
-  (empty [_]
-    (throw (UnsupportedOperationException. "XITDBHashMap is read-only")))
+  (empty [this]
+    {})
 
   (equiv [this other]
     (and (instance? clojure.lang.IPersistentMap other)

src/xitdb/hash_set.clj

@@ -15,8 +15,8 @@
 
 (deftype XITDBHashSet [^ReadHashSet rhs]
   clojure.lang.IPersistentSet
-  (disjoin [_ k]
-    (throw (UnsupportedOperationException. "XITDBHashSet is read-only")))
+  (disjoin [this k]
+    (disj (common/materialize this) k))
 
   (contains [this k]
     (operations/set-contains? rhs k))
@@ -26,11 +26,11 @@
       k))
 
   clojure.lang.IPersistentCollection
-  (cons [_ o]
-    (throw (UnsupportedOperationException. "XITDBHashSet is read-only")))
+  (cons [this o]
+    (cons o (common/materialize this)))
 
-  (empty [_]
-    (throw (UnsupportedOperationException. "XITDBHashSet is read-only")))
+  (empty [this]
+    #{})
 
   (equiv [this other]
     (and (instance? clojure.lang.IPersistentSet other)

src/xitdb/linked_list.clj

@@ -19,11 +19,11 @@
   (count [_]
     (.count rlal))
 
-  (cons [_ o]
-    (throw (UnsupportedOperationException. "XITDBLinkedArrayList is read-only")))
+  (cons [this o]
+    (cons o (common/materialize this)))
 
-  (empty [_]
-    (throw (UnsupportedOperationException. "XITDBLinkedArrayList is read-only")))
+  (empty [this]
+    '())
 
   (equiv [this other]
     (and (sequential? other)