argparse/include
Even Rouault 8f5b3e0722
Several bug fixes in usage, and improvement in usage and help
- Display mutually exclusive arguments as ``[[-a]|[-b]]`` in usage
- Add ... trailer to repeatable arguments in usage: ``[-x]...``

- Implement the following enhancements:

By default usage is reported on a single line.

The ``ArgumentParser::set_usage_max_line_width(width)`` method can be used
to display the usage() on multiple lines, by defining the maximum line width.

It can be combined with a call to ``ArgumentParser::set_usage_break_on_mutex()``
to ask grouped mutually exclusive arguments to be displayed on a separate line.

``ArgumentParser::add_usage_newline()`` can also be used to force the next
argument to be displayed on a new line in the usage output.

The following snippet

```cpp
    argparse::ArgumentParser program("program");
    program.set_usage_max_line_width(80);
    program.set_usage_break_on_mutex();
    program.add_argument("--quite-long-option-name").flag();
    auto &group = program.add_mutually_exclusive_group();
    group.add_argument("-a").flag();
    group.add_argument("-b").flag();
    program.add_argument("-c").flag();
    program.add_argument("--another-one").flag();
    program.add_argument("-d").flag();
    program.add_argument("--yet-another-long-one").flag();
    program.add_argument("--will-go-on-new-line").flag();
    program.add_usage_newline();
    program.add_argument("--new-line").flag();
    std::cout << program.usage() << std::endl;
```

will display:
```console
Usage: program [--help] [--version] [--quite-long-option-name]
               [[-a]|[-b]]
               [-c] [--another-one] [-d] [--yet-another-long-one]
               [--will-go-on-new-line]
               [--new-line]
```

Furthermore arguments can be separated into several groups by calling
``ArgumentParser::add_group(group_name)``. Only optional arguments should
be specified after the first call to add_group().

```cpp
    argparse::ArgumentParser program("program");
    program.set_usage_max_line_width(80);
    program.add_argument("-a").flag().help("help_a");
    program.add_group("Advanced options");
    program.add_argument("-b").flag().help("help_b");
```

will display:
```console
Usage: program [--help] [--version] [-a]

Advanced options:
               [-b]
```
2024-03-13 02:09:44 +01:00
..
argparse Several bug fixes in usage, and improvement in usage and help 2024-03-13 02:09:44 +01:00