avoid golang error boilerplate (but, this is evil code)

error_and_die.go

package main

import (
	"fmt"
)

func main() {
	err := test1()
	fmt.Println("test1:", err) // "test1: error message"

	n, err := test2()
	fmt.Println("test2:", n, err) // "test2: -1 error message"

	n, err = test3()
	fmt.Println("test3:", n, err) // "test3: 0 <nil>"
}

func test1() (err error) {
	defer revival(func(e error) {
		// overwrite return value
		err = e
	})

	orDie(fmt.Errorf("error message"))
	return nil
}

func test2() (n int, err error) {
	defer revival(func(e error) {
		// overwrite return value
		err = e
		n = -1
	})

	orDie(fmt.Errorf("error message"))
	return 0, nil
}

func test3() (n int, err error) {
	defer revival(func(e error) {
		// overwrite return value
		err = e
		n = -1
	})

	orDie(nil)
	return 0, nil
}

//----------------------------------

func orDie(err error) {
	panic(err)
}

func revival(f func(error)) {
	msg := recover()
	if msg != nil {
		if err, ok := msg.(error); ok {
			f(err)
		} else {
			f(fmt.Errorf("%v", msg))
		}
	}
}