.

wcfs/internal/xbtree.py

@@ -58,9 +58,9 @@ Topology encoding specification:
 A Tree is encoded by level-order traversal, delimiting layers with "/".
 Inside a layer Tree and Bucket nodes are signalled as
 
-    "T<keys>"       ; Tree
-    "B<keys>"       ; Bucket with only keys
-    "B<keys+values>"; Bucket with keys and values
+    "T<keys>"           ; Tree
+    "B<keys>"           ; Bucket with only keys
+    "B<keys+values>"    ; Bucket with keys and values
 
 Keys are represented as ","-delimited list of integers. For example Tree
 or Bucket with [1,3,5] keys are represented as
@@ -73,6 +73,11 @@ example Bucket corresponding to {1:1, 2:4, 3:9} is represented as
 
     "B1:1,2:4,3:9"  ; Bucket([1,2,3], [1,4,9])
 
+Empty keys+values are represented as ":" - an empty Bucket for key->value
+mapping is represented as
+
+    "B:"            ; Bucket([], [])
+
 Nodes inside one layer are delimited with "-". For example a layer consisting
 of an empty Tree, a Tree with [1,3] keys, and Bucket with [4,5] keys is
 represented as