Go：从延迟返回

Question

如果函数发生恐慌（在 Go 中），我想从它返回一个错误：func getReport(filename string) (rep report, err error) {    rep.data = make(map[string]float64)    defer func() {        if r := recover(); r != nil {            fmt.Println("Recovered in f", r)            err, _ = r.(error)            return nil, err        }    }()    panic("Report format not recognized.")    // rest of the getReport function, which can try to out-of-bound-access a slice    ...} 我似乎误解了恐慌和推迟的概念。有人可以启发我吗？

Answer 1

看看这个

package main

import "fmt"

func iWillPanic() {

    panic("ops, panic")

}

func runner() (s string) {

    rtnValue := ""

    defer func() {

        if r := recover(); r != nil {

            // and your logs or something here, log nothing with panic is not a good idea

            rtnValue = "don't panic" // modify the return value, and it will return

        }

    }()

    iWillPanic()

    return rtnValue

}

func main() {

    fmt.Println("Return Value:", runner())

}