【GO语言学习之路】GO语言中的变量1.标识符2.关键字3.变量3.1 Go语言中变量的声明3.2 批量声明3.3 变量的初始化3.4 短变量声明3.5匿名变量4.常量5.iota

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break        default      func         interface    select
    case         defer        go           map          struct
    chan         else         goto         package      switch
    const        fallthrough  if           range        type
    continue     for          import       return       var

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Constants:    true  false  iota  nil

        Types:    int  int8  int16  int32  int64  
                  uint  uint8  uint16  uint32  uint64  uintptr
                  float32  float64  complex128  complex64
                  bool  byte  rune  string  error

    Functions:   make  len  cap  new  append  copy  close  delete
                 complex  real  imag
                 panic  recover

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var 变量名 变量类型

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var name string
var age int
var isOk bool

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var (
	a string
    b int
    c bool
    d float32
)

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func main() {

	var (
		test01 string
		test02 int
		test03 bool
		test04 float32
	)
	fmt.Println(test01, test02, test03, test04)

}

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 0 false 0

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var 变量名 类型=表达式

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var name string="wql"
var age int =18

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var name,age="wql",20

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var name = "wql"
var age = 18

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package main

//告诉程序需要fmt包，fmt具有打印输出的函数
import "fmt"

var n int

func main() {
	b := 123
	fmt.Println(b)
}

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package main

//告诉程序需要fmt包，fmt具有打印输出的函数
import "fmt"

func main() {


	x, _ := foo()
	_, y := foo()
	fmt.Println("x=", x)
	fmt.Println("y=", y)

}

func foo() (int, string) {
	return 10, "wql"
}

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123 123
hello wql
x= 10
y= wql

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	const pi = 3.12
	const e = 2.7
	fmt.Println(pi, e)

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	const(
		p1 = 2
		p2 = 4
	)

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	const(
		p3 = 200
		p4
		p5
	)

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	const (
		n1 = iota //0
		n2        //1
		n3        //2
		n4        //3
	)
	fmt.Println(n1, n2, n3, n4)

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0 1 2 3

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	const (
		n1 = iota //0
		n2        //1
		_
		n4 //3
	)

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	const (
		n1 = iota //0
		n2 = 100  //100
		n3 = iota //2
		n4        //3
	)

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	const (
		_  = iota
		KB = 1 << (10 * iota)
		MB = 1 << (10 * iota)
		GB = 1 << (10 * iota)
		TB = 1 << (10 * iota)
		PB = 1 << (10 * iota)
	)

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	const (
		a, b = iota + 1, iota + 2 //1,2
		c, d                      //2,3
		e, f                      //3,4
	)