1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
|
// Copyright 2013 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package main
import (
"fmt"
)
// Extend extends the slice by adding the element to the end.
func Extend(slice []int, element int) []int {
n := len(slice)
if n == cap(slice) {
// Slice is full; must grow.
// We double its size and add 1, so if the size is zero we still grow.
newSlice := make([]int, len(slice), 2*len(slice)+1)
copy(newSlice, slice)
slice = newSlice
}
slice = slice[0 : n+1]
slice[n] = element
return slice
}
// Append appends the items to the slice.
// First version: just loop calling Extend.
func Append(slice []int, items ...int) []int {
for _, item := range items {
slice = Extend(slice, item)
}
return slice
}
func main() {
// START OMIT
slice1 := []int{0, 1, 2, 3, 4}
slice2 := []int{55, 66, 77}
fmt.Println(slice1)
slice1 = Append(slice1, slice2...) // The '...' is essential!
fmt.Println(slice1)
// END OMIT
}
|