Shared functionality between argh_derive and the argh runtime.
This library is intended only for internal use by these two crates.
- Information about a particular command used for output.
- Information about the command line arguments for a given command.
- Information about a documented error code.
- Information about a flag or option.
- Information about positional arguments
- Information about a subcommand. Dynamic subcommands do not implement get_args_info(), so the command field only contains the name and description.
- The kind of flags.
- The optionality defines the requirments related to the presence of the argument on the command line.
- Write command names and descriptions to an output string.