var golang.org/x/tools/internal/event/keys.Err

3 uses

	golang.org/x/tools/internal/event/keys (current package)
		standard.go#L19: 	Err = NewError("error", "an error that occurred")

	golang.org/x/tools/internal/event
		event.go#L47: 		keys.Err.Of(err),
		event.go#L56: 		ev.Label(1).Key() == keys.Err