vet: check values for named constants as well as literals. As in:         const format = "%s"         fmt.Printf(format, "hi") Also fix a couple of bugs by rewriting the routine.
vet: check values for named constants as well as literals.
As in:
        const format = "%s"
        fmt.Printf(format, "hi")
Also fix a couple of bugs by rewriting the routine.

R=golang-dev, rsc
CC=golang-dev
http://codereview.appspot.com/6099057

h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang