如何在终止程序时错误地嵌入退出代码以使用？

Question

如何在 go 错误中嵌入退出代码，将其冒泡，然后在处理错误时使用退出代码退出？例如：func main () {  foo, err := foo()  if err != nil{    fmt.Printf("error thrown, exit code: %v", err )  }  // I can parse the exit code out of err, but that seems wrong...   // how can I exit with the exit code cleanly? do i need to create a custom error that I bubble up and handle?  os.Exit(1)}func foo() (string, err) {  bar, err := bar()  if err != nil {     return "", fmt.Errorf("foo fails b/c bar fails %v": err)  }}func bar() (string, err) {  exitCode := 208  return "", fmt.Errorf("some error happened in bar, exit code: %v", exitCode)}

Answer 1

为此，可以创建自己的实现接口的类型，然后使用错误包装（有关详细信息，请参阅此博客文章）。结果如下：error

package main

import (

    "errors"

    "fmt"

    "os"

    "strconv"

)

type fooErr int

func (e fooErr) Error() string { return strconv.Itoa(int(e)) }

func main() {

    errCode := 0

    _, err := foo()

    if err != nil {

        var e fooErr

        if errors.As(err, &e) {

            fmt.Printf("error thrown, exit code: %v", e)

            errCode = int(e)

        } else {

            fmt.Printf("error thrown, dont have a code: %v", err)

            errCode = 1 // default code...

        }

    }

    // I can parse the exit code out of err, but that seems wrong...

    // how can I exit with the exit code cleanly? do i need to create a custom error that I bubble up and handle?

    os.Exit(errCode)

}

func foo() (string, error) {

    _, err := bar()

    if err != nil {

        return "", fmt.Errorf("foo fails b/c bar fails %w", err)

    }

    return "OK", nil

}

func bar() (string, error) {

    exitCode := fooErr(208)

    return "", fmt.Errorf("some error happened in bar, exit code: %w", exitCode)

}

在操场上试试吧。