buf := new(bytes.Buffer)
	err := gob.NewEncoder(buf).Encode(fieldValue)
	return buf.Bytes(), err

// keys, so we need to use this technique to merge the
// keys.
func sanitizePolicy(r io.Reader) (io.Reader, error) {
	var buf bytes.Buffer
	e := json.NewEncoder(&buf)
	d := jstream.NewDecoder(r, 0).ObjectAsKVS().MaxDepth(10)
	sset := set.NewStringSet()
	for mv := range d.Stream() {
		if mv.ValueType == jstream.Object {
			// This is a JSON object type (that preserves key order)

				return
			}
		}

		contentType := expfmt.Negotiate(r.Header)
		w.Header().Set("Content-Type", string(contentType))

		enc := expfmt.NewEncoder(w, contentType)
		for _, mf := range mfs {
			if err := enc.Encode(mf); err != nil {
				// client may disconnect for any reasons
				// we do not have to log this.
				return
			}
		}

		if err != nil {
			log.Fatalf("loading imports: %v\n%s", err, out)
		}

		var stdPackages []string
		importMap := make(map[string]map[string]string)
		importDir := make(map[string]string)
		dec := json.NewDecoder(bytes.NewReader(out))
		for {
			var pkg struct {
				ImportPath, Dir string
				ImportMap       map[string]string
				Standard        bool
			}
			err := dec.Decode(&pkg)
			if err == io.EOF {