1// Copyright 2019 The Go Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style
3// license that can be found in the LICENSE file.
4
5package a
6
7type A interface {
8	M(i interface{}) interface{}
9}
10
11var a1 A
12var a2 A
13
14func V(p A, k, v interface{}) A {
15	defer func() { a1, a2 = a2, a1 }()
16	return a1
17}
18