package main

import (
    "fmt"
)

/**
    变量声明，可用于全局和局部变量声明
    var vName type
    
    只能用于全局变量声明
    var (
        vName1 type
        vName2 type
        ...
    )
    
    变量初始化
    var vName type = value
    var vName = value
    vName := value
    
    常量
    const cName type ＝ value
    const cName = value
    const (
        cName1 = value
        cName2 = value
    )
    
    预定义常量: true false iota
    const (
        a = 1 << iota
        b = 1 << iota
        c = 1 << iota
    )
*/

const (
    a = iota
    b
    c
    d
)

// 枚举
const (
    Sunday = iota
    Monday
    Tuesday
    Wednesday
    Thursday
    Friday
    Saturday
)

func main() {
    fmt.Println(a, b, c, d)
}