code: function isValidMethodCharacter(ch) {
    if (!ch) {
      return false
    }
  
    return (
      inRange(code(ch), 0x30, 0x39) ||
      inRange(code(ch), 0x61, 0x7a)
    )
  }
docs: method     = 1*methodchar methodchar = %x61-7A / DIGIT