Golang foundation -- slicing several declaration methods

1, Statement slice It's a slice , No space was allocated after the declaration ,len yes 0

var slice1 []int

2, Statement slice It's a slice , And initialize , The default value is 123, The length is 3

slice1 := []int{
    1,2,3}

3, Statement slice It's a slice , Adopted after declaration make Distribute 3 Space , The initialization value is 0

var slice1 []int = make([]int,3)

4, adopt := Automatically deduce and judge slice It's a slice , adopt make Distribute 3 Space , The default value is 0

slice1 := make([]int,3)

Here is the complete executable code , Self testing （ The following code has a syntax error ）

package main

import "fmt"

func main(){
    

	// 1, Statement slice It's a slice , When only := No space was allocated after the declaration ,len yes 0
	var slice1 []int
	
	// 2, Statement slice It's a slice , And initialize , The default value is 123, The length is 3
	slice2 := []int{
    1,2,3}


	// 3, Statement slice It's a slice , Assign after declaration 3 Space , The default value for initialization is 0
	var slice3 []int = make([]int,3)

	// 4, adopt  :=  Deduce slice It's a slice 
	slice4 := make([]int,3)	
	

	fmt.Printf("len = %d","slice = %v\n",len(slice1),slice)
	// %v Yes, print out all details 


	//  Judge a slice Is it empty 
	if slice3 == nil {
    
		fmt.Println("slice1 It's an empty slice ")
	}else{
    
		fmt.Println("slice1 There is room ")
	}
}