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by James Page
Import upstream version 1.2 |
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// cmpout
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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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