golang闭包

http://blog.51cto.com/speakingbaicai/1703229
https://www.jianshu.com/p/fa21e6fada70

所谓闭包就是一个函数“捕获”了和它在同一作用于的其他常量和变量。

package main

import "fmt"

func addNumber(x int) func(int) {
    fmt.Printf("x: %d, addr of x:%p\n", x, &x)
    return func(y int) {
        k := x + y
        x = k
        y = k
        fmt.Printf("x: %d, addr of x:%p\n", x, &x)
        fmt.Printf("y: %d, addr of y:%p\n", y, &y)
    }
}

func main() {
    addNum := addNumber(5)
    addNum(1)
    addNum(1)
    addNum(1)

    fmt.Println("---------------------")

    addNum1 := addNumber(5)
    addNum1(1)
    addNum1(1)
    addNum1(1)
}

x: 5, addr of x:0xc4200140c8
x: 6, addr of x:0xc4200140c8
y: 6, addr of y:0xc420014100
x: 7, addr of x:0xc4200140c8
y: 7, addr of y:0xc420014118
x: 8, addr of x:0xc4200140c8
y: 8, addr of y:0xc420014130
---------------------
x: 5, addr of x:0xc420014148
x: 6, addr of x:0xc420014148
y: 6, addr of y:0xc420014158
x: 7, addr of x:0xc420014148
y: 7, addr of y:0xc420014170
x: 8, addr of x:0xc420014148
y: 8, addr of y:0xc420014188