2018-05-01 14:46:39 -04:00
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// Copyright 2018 Google LLC
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// https://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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2018-04-03 13:13:15 -07:00
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package main
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2018-04-27 13:44:54 -04:00
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import (
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"fmt"
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)
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2018-04-03 13:13:15 -07:00
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func main() {
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bar, cleanup := injectBar()
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fmt.Println(*bar)
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cleanup()
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fmt.Println(*bar)
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}
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type Foo int
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type Bar int
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func provideFoo() (*Foo, func()) {
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foo := new(Foo)
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*foo = 42
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return foo, func() { *foo = 0 }
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}
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func provideBar(foo *Foo) (*Bar, func()) {
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bar := new(Bar)
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*bar = 77
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return bar, func() {
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if *foo == 0 {
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panic("foo cleaned up before bar")
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}
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*bar = 0
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}
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}
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