Variables

How

var a  // 不定型別的變數
var a int // 宣告成 int
var a int = 10 // 初始化同時宣告
var a, b int // a 跟 b 都是 intvar a, b = 0, ""
var a int , b string
a := 0
a, b, c := 0, true, "tacolin" // 這樣就可以不同型別寫在同一行
var(
    a bool = false // 記得要不同行，不然會錯
    b int
    c = "hello"
)

Where

Go is lexically scoped using blocks!

package main

import "fmt"

var x string = "Hello World"

func main() {
    var y string = "Hello AAA"
    fmt.Println(x)                //Hello World
}

func aaa() {
    fmt.Println(x)                //Hello World
    fmt.Println(y)                //undefined: y
}

func bbb() {
    fmt.Println(x)                //Hello World
}

What

Go also has support for constants. Constants are basically variables whose values cannot be changed later.

const x string = "Owen is a good boy!"
x = "James is better."            //cannot assign to x
var y string = "Disney kiss Ken"
y = "Louis kiss Ken"            //it's okay!