Rust derive-based argument parsing optimized for code size
...Subcommands can be modeled without much boilerplate, letting you structure larger CLIs while keeping each command self-contained. The overall feel is “get out of your way”: minimal setup, zero magic, and a straightforward path from argv to validated inputs.
...When the lexer identifies a token that has a named event associated with it, it passes the token to the parser method associated with that event. A lexer can dispatch token events to any number of parsers.
JPlex is steadily being improved, and the Subversion repo will almost always be newer and better than the binary download.