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59 lines
1.0 KiB
59 lines
1.0 KiB
4 months ago
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// Copyright 2011 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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// This file contains the code snippets included in "Defer, Panic, and Recover."
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package main
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import "fmt"
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import "io" // OMIT
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import "os" // OMIT
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func main() {
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f()
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fmt.Println("Returned normally from f.")
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}
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func f() {
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defer func() {
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if r := recover(); r != nil {
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fmt.Println("Recovered in f", r)
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}
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}()
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fmt.Println("Calling g.")
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g(0)
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fmt.Println("Returned normally from g.")
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}
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func g(i int) {
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if i > 3 {
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fmt.Println("Panicking!")
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panic(fmt.Sprintf("%v", i))
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}
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defer fmt.Println("Defer in g", i)
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fmt.Println("Printing in g", i)
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g(i + 1)
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}
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// STOP OMIT
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// Revised version.
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func CopyFile(dstName, srcName string) (written int64, err error) {
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src, err := os.Open(srcName)
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if err != nil {
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return
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}
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defer src.Close()
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dst, err := os.Create(dstName)
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if err != nil {
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return
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}
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defer dst.Close()
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return io.Copy(dst, src)
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}
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// STOP OMIT
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