message: das.cli: clean up minor issues
  more comments
  formatting changes
  simplify code
diff: @@ -20,6 +20,10 @@ namespace das
  {
  namespace cli
  {
  + /*---------.
  + | Errors. |
  + `---------*/
  +
  /// Command line error
  class Error
  : public elle::Error
  @@ -116,6 +120,10 @@ namespace das
  class CLI_Symbol
  {};
  + /*----------.
  + | Options. |
  + `----------*/
  +
  struct Option
  {
  Option(char short_name = 0,
  @@ -217,6 +225,7 @@ namespace das
  public:
  using Super = std::conditional_t<
  std::is_same<Default, void>::value, Empty, Default>;
  + /// Whether a default value was specified.
  static bool constexpr default_has = !std::is_same<Default, void>::value;
  Value(std::conditional_t<default_has, Default, int> const& d,
  @@ -430,8 +439,7 @@ namespace das
  void
  _check_remaining() const
  {
  - if (!--this->_remaining)
  - if (!this->_args.empty())
  + if (!--this->_remaining && !this->_args.empty())
  {
  if (is_option(*this->_args.begin()))
  throw UnknownOption(*this->_args.begin());
  @@ -595,11 +603,8 @@ namespace das
  else
  {
  if (value.empty())
  - {
  - Default const& couille = p.defaults;
  ELLE_DEBUG(
  - "no occurences, default value is %s", couille.value);
  - }
  + "no occurences, default value is %s", p.defaults.Default::value);
  return V(p.defaults, Head::name(), pos, args,
  std::move(value), counter);
  }
  