1 files changed, 43 insertions, 0 deletions
diff --git a/content/slices/prog130.go b/content/slices/prog130.go
new file mode 100644
index 0000000..ff514b5
--- /dev/null
+++ b/content/slices/prog130.go
@@ -0,0 +1,43 @@
+// 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
+}