区块链技术Go语言——变量篇

Posted 2022-12-07 说到做到_我的忍道

/*
* @Author: mrtao
* @Date:   2018-08-11 10:56:38
* @Last Modified by:   mrtao
* @Last Modified time: 2018-08-12 11:04:04
 */
package main

import "fmt"

func main() 

	var a int
	a = 20

	fmt.Println("a =", a)

	c := 30.33

	fmt.Println("c = ", c)

	// d = 10
	// fmt.Println("d =", d)

	const e = 10
	// e = 20
	fmt.Println("e =", e)

	// 不同类型变量的定义
	/*var f int
	var g float64*/
	var (
		f int
		g float64
	)

	f, g = 10, 3.14
	fmt.Println("f =", f)
	fmt.Println("g =", g)

	// 自动推倒类型
	const (
		i = 10
		j = 3.14
	)
	fmt.Println("i =", i)
	fmt.Println("j =", j)

	/*iota 枚举
	1. iota 常量自动生成器，每隔一行，自动累加1
	2. iota 给常量赋值*/
	const (
		l = iota
		m = iota
		n = iota
	)
	fmt.Printf("l = %d, m = %d, n = %d\\n", l, m, n)
	// 3. iota 遇到const, 重置为0
	const o = iota
	fmt.Printf("o = %d\\n", o)

	// 4. iota 可以只写一个
	const (
		l1 = iota
		m1
		n1
	)
	fmt.Printf("l1 = %d, m1 = %d, n1 = %d\\n", l1, m1, n1)
	// 5. 如果是同一行， 值都一样
	const (
		l2         = iota
		m2, m3, m4 = iota, iota, iota
		n2         = iota
	)
	fmt.Printf("l2 = %d, m2 = %d, m3 = %d, m4 = %d, n2 = %d\\n", l2, m2, m3, m4, n2)

	var f1 float32
	f1 = 3.14
	fmt.Println("f1 = ", f1)

	f2 := 3.14
	fmt.Printf("f2 type is %T\\n", f2)

	var t complex128
	t = 2.1 + 3.14i
	fmt.Println("t = ", t)