.

wcfs/internal/xbtree/δbtail.go

@@ -56,9 +56,12 @@ type Value  = zodb.Oid // XXX assumes key points to IPersistent
 //
 // A tree nodes become tracked via Track(path) request.
 //
-// XXX which operations are provided.
+// It provides the following operations:
 //
-//	- Get(root, key, at)
+//   - Track(path)		- start tracking tree nodes and keys; root=path[0], keys=path[-1].keys
+//   - Get(root, key, at)	- get root[key] @at assuming root[key] ∈ tracked
+//   - Update(δZ)		- update BTree δ tail given raw ZODB changes
+//   - ForgetPast(revCut)	- forget changes past revCut
 //
 // An example for tracked set is a set of visited BTree paths.
 // There is no requirement that tracked set belongs to only one single BTree.
@@ -240,7 +243,7 @@ func (btail *ΔTail) Update(δZ *zodb.EventCommit) []ΔTree {
 // XXX only tracked set?
 //
 // XXX at must ∈ (tail, head]	XXX [tail ?
-// XXX key must be tracked?
+// XXX key must be tracked -> yes
 func (btail *ΔTail) Get(root *Tree, key Key, at zodb.Tid) (value Value, ok bool, rev zodb.Tid, revExact bool) {
 	// XXX key not tracked		-> panic
 	// XXX at not ∈ (tail, head]	-> panic