Cmdliner allows the declarative definition of command line interfaces in OCaml.
It provides a simple and compositional mechanism to convert command line arguments to OCaml values and pass them to your functions. The module automatically handles syntax errors, help messages and UNIX man page generation. It supports programs with single or multiple commands (like darcs or git) and respects most of the POSIX and GNU conventions.
Cmdliner has no dependencies and is distributed under the ISC license.