Class arguments

examples/utils.hpp:194–306

namespace libremidi::examples
{
struct arguments
{
  libremidi::API api{libremidi::API::UNSPECIFIED};
  int input_port{0};
  int output_port{0};
  int count{50};
  bool virtual_port{};

  static std::string api_list()
  {
    std::string ret;
    ret.reserve(64);
    auto apis = libremidi::available_apis();
    for (auto api : apis)
    {
      ret += libremidi::get_api_name(api);
      ret += ", ";
    }
    if (apis.size() > 0)
      ret.resize(ret.size() - 2);
    return ret;
  }

  arguments(int argc, const char** argv)
  {
    args::ArgumentParser parser("libremidi example");
    args::HelpFlag help(parser, "help", "Display this help menu", {'h', "help"});

    args::ValueFlag<std::string> opt_api(parser, "api", "API to use (" + api_list() + ")", {'a'});
    args::ValueFlag<int> opt_port(parser, "input", "Input port to open", {'i'});
    args::ValueFlag<int> opt_out_port(parser, "output", "Output port to open", {'o'});
    args::ValueFlag<int> opt_count(parser, "count", "Number of bytes", {'n'});
    args::Flag opt_virt(
        parser, "virtual", "Open a virtual port instead of an existing one", {'v'});

    args::CompletionFlag completion(parser, {"complete"});

    try
    {
      parser.ParseCLI(argc, argv);
    }
    catch (args::Help)
    {
      std::cout << parser;
      std::exit(1);
    }
    catch (args::ParseError e)
    {
      std::cerr << e.what() << std::endl;
      std::cerr << parser;
      std::exit(1);
    }
    catch (args::ValidationError e)
    {
      std::cerr << e.what() << std::endl;
      std::cerr << parser;
      std::exit(1);
    }