Clean up callback interfaces.

symbols.go

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package gae
+
+type stopErr struct{}
+
+func (stopErr) Error() string { return "stop iteration" }
+
+// Stop is understood by various services to stop iterative processes. Examples
+// include datastore.Interface.Run's callback.
+var Stop error = stopErr{}

[dnj, 2015/12/14 22:35:03]

Why not just errors.New("stop iteration")?

[iannucci, 2015/12/14 23:03:09]

because then golint complains that it's not ErrStop >_<