type mode = [ | `Byte| `Native| `Ppx_driver| `Preprocessor| `Toploop
]type t = [ | `Archive of [ `NoPlugin | `Plugin ] * mode| `Description| `Mode of [ `None | `TooMany ]| `Plugin of [ `NoPlugin | `Plugin ] * mode| `Requires| `Version
]val compare : 'a -> 'a -> int