defer 里修改返回值的几种情况

defer_and_return.go

package main

import (
	"fmt"
)

func main() {
	fmt.Println(f())
	fmt.Println(f1())
	fmt.Println(f2())
	fmt.Println(f3())
}

func f() (result int) {
	defer func() {
		result++
	}()
	return 0
}

func f1() (r int) {
	t := 5
	defer func() {
		t = t + 5
	}()
	return t
}

func f2() (r int) {
	r = 2
	defer func() {
		fmt.Println("input: ", r)
		r = r + 5
	}()
	return 1
}

func f3() int {
	r := 10
	defer func() {
		r++
	}()
	return r
}

/*
1
5
input:  1
6
10
*/