1 files changed, 42 insertions, 0 deletions
diff --git a/doc/progs/eff_sequence.go b/doc/progs/eff_sequence.go
new file mode 100644
index 000000000..11c885abf
--- /dev/null
+++ b/doc/progs/eff_sequence.go
@@ -0,0 +1,42 @@
+// Copyright 2009 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"
+	"sort"
+)
+
+func main() {
+	seq := Sequence{6, 2, -1, 44, 16}
+	sort.Sort(seq)
+	fmt.Println(seq)
+}
+
+type Sequence []int
+
+// Methods required by sort.Interface.
+func (s Sequence) Len() int {
+	return len(s)
+}
+func (s Sequence) Less(i, j int) bool {
+	return s[i] < s[j]
+}
+func (s Sequence) Swap(i, j int) {
+	s[i], s[j] = s[j], s[i]
+}
+
+// Method for printing - sorts the elements before printing.
+func (s Sequence) String() string {
+	sort.Sort(s)
+	str := "["
+	for i, elem := range s {
+		if i > 0 {
+			str += " "
+		}
+		str += fmt.Sprint(elem)
+	}
+	return str + "]"
+}