This was brought to my attention because a user thought that because
the file was named "example.go" it served as an example of good coding
practice.  It's not an example, of course, but may as well use a more
idiomatic style anyhow.

Change-Id: I7aa720f603f09f7d597fb7536dbf46ef09144e28
Reviewed-on: https://go-review.googlesource.com/1902Reviewed-by: Minux Ma <minux@golang.org>