--- /dev/null
+// Copyright 2014 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.
+
+// Signed integers spanning zero.
+
+package main
+
+import "fmt"
+
+type Num int
+
+const (
+ m_2 Num = -2 + iota
+ m_1
+ m0
+ m1
+ m2
+)
+
+func main() {
+ ck(-3, "Num(-3)")
+ ck(m_2, "m_2")
+ ck(m_1, "m_1")
+ ck(m0, "m0")
+ ck(m1, "m1")
+ ck(m2, "m2")
+ ck(3, "Num(3)")
+}
+
+func ck(num Num, str string) {
+ if fmt.Sprint(num) != str {
+ panic("num.go: " + str)
+ }
+}