Refactor a bit.

service/memcache/interface.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 memcache
+
+// Interface is the full interface to the memcache service.
+type Interface interface {
+        NewItem(key string) Item
+
+        Add(item Item) error
+        Set(item Item) error
+        Get(key string) (Item, error)
+        Delete(key string) error
+        CompareAndSwap(item Item) error
+
+        AddMulti(items []Item) error
+        SetMulti(items []Item) error
+        GetMulti(keys []string) (map[string]Item, error)
+        DeleteMulti(keys []string) error
+        CompareAndSwapMulti(items []Item) error
+
+        Increment(key string, delta int64, initialValue uint64) (newValue uint64, err error)
+        IncrementExisting(key string, delta int64) (newValue uint64, err error)
+
+        Flush() error
+
+        Stats() (*Statistics, error)
+}