.

go/zodb/storage/demo/demo.go

@@ -71,21 +71,20 @@ func (e *baseMutatedError) Error() string {
 	return fmt.Sprintf("base.head mutated from @%s to @%s", e.baseAt0, e.baseHead)
 }
 
-// baseError is reported on error detected on Storage.base .
-type baseError struct {
+// baseErrorEvent is reported on error event detected on Storage.base .
+type baseErrorEvent struct {
 	err error
 }
 
-func (e *baseError) Error() string {
-	return fmt.Sprintf("base: error: %s", e.err)
+func (e *baseErrorEvent) Error() string {
+	return fmt.Sprintf("base: error event: %s", e.err)
 }
 
-func (e *baseError) Cause() error  { return e.err }
-func (e *baseError) Unwrap() error { return e.err }
+func (e *baseErrorEvent) Cause() error  { return e.err }
+func (e *baseErrorEvent) Unwrap() error { return e.err }
 
 
-// watcher detects base mutation and proxies δ events to user watchq.
-// it runs as separate goroutine.
+// watcher task detects base mutation and proxies δ events to user watchq.
 func (d *Storage) watcher(ctx context.Context) error {
 	if d.watchq != nil {
 		defer close(d.watchq)
@@ -97,7 +96,7 @@ func (d *Storage) watcher(ctx context.Context) error {
 		case <-ctx.Done():
 			return ctx.Err()
 
-		// event on base -> base mutated + shutdown
+		// event on base -> base mutated/error + shutdown
 		case event, ok := <-d.baseWatchq:
 			if !ok {
 				// base closed
@@ -111,7 +110,7 @@ func (d *Storage) watcher(ctx context.Context) error {
 				edown = &baseMutatedError{d.baseAt0, event.Tid}
 
 			case *zodb.EventError:
-				edown = &baseError{event.Err}
+				edown = &baseErrorEvent{event.Err}
 
 			default:
 				edown = fmt.Errorf("base: unexpected event %T", event)
@@ -138,7 +137,7 @@ func (d *Storage) watcher(ctx context.Context) error {
 	}
 }
 
-// shutdown marks Storage as no longer being operational due to reason.
+// shutdown marks Storage as no longer operational due to reason.
 func (d *Storage) shutdown(reason error) {
 	d.downOnce.Do(func() {
 		d.downErr = reason
@@ -160,7 +159,7 @@ func (d *Storage) Close() (err error) {
 	errδ    := d.δ.Close()
 	errBase := d.base.Close()
 
-	// cancel watcher. don't propagate its error to Close - watcher error
+	// cancel watcher; don't propagate its error to Close - watcher error
 	// goes to watchq and op errors.
 	d.watchCancel()
 	_ = d.watchWG.Wait()
@@ -254,8 +253,8 @@ func (d *Storage) Load(ctx context.Context, xid zodb.Xid) (_ *mem.Buf, _ zodb.Ti
 		}
 	}
 
-	// cap .at in xid to .baseAt0 (we convert it back on error return, and
-	// it makes more robust wrt simultaneous base mutation).
+	// cap xid.At to .baseAt0 (we convert it back on error return, and
+	// it makes Load more robust wrt simultaneous base mutation).
 	xidBase := xid
 	if xid.At > d.baseAt0 {
 		xidBase.At = d.baseAt0