cxx20opts

C++20 (17) command line parsing library

Tasks:

• Basic argument processing - wrapping with std::string_view (since C++17) (don't usage C++ std::string - redundant memory allocation).
• Help generator, with custom options, user-defind, default - basic help output.
• Option With small -f path and full name --file path. Space or ( and? ) equals sign (user defind, default - space) - separator option and argument.
• Exception free overloading.
• Optional windwos style command line argumets generate.

Basic API (is disscussed):

• class options - observer argc, argv.

cxx20opts::options opts{argc, argv};

• obj[ "keyname"sv ], obj[ arg_number - decltype (sizeof 0) ], .at<T>(sv/arg_number) - as default, returned std::string_view or concept (since C++20) string (is abstract string, user impl-defined). with support cast to user-defined type.

opts["file"sv] // returned std::filesystem::path (if before defined)

• raw() - get parir with raw argc && argv.

obj.raw() -> std::pair<int, char**> /* or concept pair, default usage - std::pair */ 

• add_option()

options.add_option(option{}).add_option({});

// or
options.option(option{}, option{}, option{});

// or
options.option(option{}
| option{}
| option{}
| option{}
);

• options.add_options(); // Is this really necessary?

• etc...