cmdparser.cpp

for (int i = 1; i < argc; ++i)
{
	const std::string arg = argv[i];
	if (expectedArgument && arg[0] != '-')
	{
		items.back().hasArgument = true;
	}
	else
	{
		if (arg[0] == '-' && !noMoreOptions)
		{
			if (arg.size() == 2 && arg[1] == '-')
			{
				// -- means no more options. only positional arguments from now on
				noMoreOptions = true;
			}
			else if (arg.size() > 1 && arg[1] == '-')
			{
				// --long-argument
				const size_t pos = arg.find('=');
				const std::string name = arg.substr(2, pos == std::string::npos ? std::string::npos : pos - 2);
				const auto option = options.find(name);
				if (option == options.end())
				{
					throw CmdParserException(std::string("Unknown option --") + name);
				}
				else
				{
					const std::string argument = pos == std::string::npos ? std::string() : arg.substr(pos + 1);
					items.emplace_back(name, argument, pos != std::string::npos);
					expectedArgument = pos == std::string::npos && (*option).second.argument.size() != 0;
				}
			}
			else if (arg.size() > 1 && arg[1] != '-')
			{
				// -abc short argument
				for (auto it = ++arg.begin(); it != arg.end(); ++it)
				{
					const auto option = options.find(std::string({*it}));
					if (option == options.end())
					{
						throw CmdParserException(std::string("Unknown option -") + *it);
					}
					else
					{
						items.emplace_back(std::string({*it}), std::string(), false);
						expectedArgument = (*option).second.argument.size() != 0;
					}
				}
			}
			else // arg.size() == 1
			{
				// single - is a positional argument. used to mean stdin and similar
				positional.push_back(arg);
				noMoreOptions = true; // we do not allow any more options after the first positional argument
			}
		}
		else
		{
			auto cmdIt = std::find_if(currentCommand.commands.begin(), currentCommand.commands.end(), [arg](const CmdSubcommand &cmd)
			{
				return std::find(cmd.names.begin(), cmd.names.end(), arg) != cmd.names.end();
			});
			if (!noMoreOptions && cmdIt != currentCommand.commands.end())
			{
				commands.push_back(*cmdIt);
				currentCommand = *cmdIt;
				const auto newOptions = currentCommand.mappedOptions();
				options.insert(newOptions.begin(), newOptions.end());
			}
			else
			{
				positional.push_back(arg);
			}
		}
	}
}