docs: def fmt_val(val, shorten=True):
      """Format a value for inclusion in an 
      informative text string.
      """
      val = repr(val)
      max = 50
      if shorten:
          if len(val) > max:
              close = val[-1]
              val = val[0:max-4] + "..."
              if close in (">", "'", '"', ']', '}', ')'):
                  val = val + close
      return val