golang bug337 代码
文件路径：/test/fixedbugs/bug337.go
/ errorcheck
/ Copyright 2011 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.
/ Issue 1722.
/ Check that the error messages says
/ bug337.go:16: len("foo") not used
/ and not
/ bug337.go:16: 3 not used
package main
func main() {
len("foo") / ERROR "len|value computed is not used"
}