mid_match?

# File lib/scanf.rb, line 477
    def mid_match?
      return false unless @matched
      cc_no_width    = letter == '[' &&! width
      c_or_cc_width  = (letter == 'c' || letter == '[') && width
      width_left     = c_or_cc_width && (matched_string.size < width)

      return width_left || cc_no_width
    end