.

wcfs/internal/xbtree/blib/rangeset.go

@@ -89,9 +89,8 @@ func (A *RangedKeySet) UnionInplace(B *RangedKeySet) {
 	defer A.verify()
 
 	// XXX dumb
-	//for _, r := range B.rangev {
-	for _, r := range B.AllRanges() {
-		A.AddRange(r)
+	for _, e := range B.m.entryv {
+		A.AddRange(e.KeyRange)
 	}
 }
 
@@ -101,12 +100,11 @@ func (A *RangedKeySet) DifferenceInplace(B *RangedKeySet) {
 	defer A.verify()
 
 	// XXX dumb
-//	for _, r := range B.rangev {
-	for _, r := range B.AllRanges() {
+	for _, e := range B.m.entryv {
 		if A.Empty() {
 			break
 		}
-		A.DelRange(r)
+		A.DelRange(e.KeyRange)
 	}
 }
 
@@ -142,7 +140,14 @@ func (S *RangedKeySet) Clear() {
 //
 // TODO -> iter?
 func (S *RangedKeySet) AllRanges() /*readonly*/[]KeyRange {
-	return []KeyRange(S.m.AllRanges())
+	// TODO we could use unsafe and cast .m.AllRanges to []KeyRange to avoid extra alloc/copy
+	// return []KeyRange(S.m.AllRanges())
+	ev := S.m.AllRanges()
+	rv := make([]KeyRange, len(ev))
+	for i := range ev {
+		rv[i] = ev[i].KeyRange
+	}
+	return rv
 }
 
 // String

wcfs/internal/xbtree/blib/rangeset_test.go

@@ -25,6 +25,7 @@ import (
 )
 
 func TestRangedKeySetTypes(t *testing.T) {
+	// verify that size(void) == 0  and  that _RangedMap_voidEntry has the same layout as KeyRange
 	sizeVoid := unsafe.Sizeof(void{})
 	if sizeVoid != 0 {
 		t.Errorf("sizeof(void) = %d  ; want 0", sizeVoid)