Go ppend() 和 copy() 函数

package main



import "fmt"



func main() {

   var numbers []int

   printSlice(numbers)



   /* append allows nil slice */

   numbers = append(numbers, 0)

   printSlice(numbers)



   /* add one element to slice*/

   numbers = append(numbers, 1)

   printSlice(numbers)



   /* add more than one element at a time*/

   numbers = append(numbers, 2,3,4)

   printSlice(numbers)



   /* create a slice numbers1 with double the capacity of earlier slice*/

   numbers1 := make([]int, len(numbers), (cap(numbers))*2)



   /* copy content of numbers to numbers1 */

   copy(numbers1,numbers)

   printSlice(numbers1)   

}

func printSlice(x []int){

   fmt.Printf("len=%d cap=%d slice=%v\n",len(x),cap(x),x)

}