anchor.diff:                'message-descriptor)
          (print-text-format value :indent (+ indent 2)
                                   :stream stream
  -                                :name (proto-name field)
  +                                :name name
                                   :print-name print-name
                                   :pretty-print pretty-print))
         ((typep desc 'enum-descriptor)
  
positive.code:       nil)))
  
  (defun print-repeated-field
      (values field &key (indent 0) (stream *standard-output*) (print-name t) (pretty-print t))
    "Print the text format of a single field which is not repeated.
  
  Parameters:
    VALUES: The list or vector of values in the field to print.
    FIELD: The field-descriptor of the field.
    INDENT: If supplied, indent the text by INDENT spaces.
    STREAM: The stream to output to.
    PRINT-NAME: Whether or not to print the name of the field.
    PRETTY-PRINT: When true, print newlines and indentation."
    (unless values
      (return-from print-repeated-field nil)) ; If values is NIL, then there is nothing to do.
    (let ((type (proto-class field))
          (desc))
      (cond
        ((scalarp type)
         (doseq (v values)
                (print-scalar v type (proto-name field) stream
                              (and pretty-print indent))))
        ((typep (setq desc (or (find-message type)
                               (find-enum type)
  
negative.code:        (when value
           (let ((value (funcall (proto-serializer desc) value))
                 (type  (proto-proto-type desc)))
             (print-scalar value type name stream
                           (and pretty-print indent)))))
        ;; todo(benkuehnert): use specified map format
        ((typep desc 'map-descriptor)
         (let ((key-class (map-descriptor-key-class desc))
               (val-class (map-descriptor-val-class desc)))
           (if pretty-print
               (format stream "~&~VT~A: {~%" (+ 2 indent) name)
               (format stream "~A: {" name))
           (flet ((print-entry (k v)
                    (format stream "~&~VT" (+ 4 indent))
                    (print-scalar k key-class nil stream nil)
  