Makefile for installing an OCaml library

Question

What are the things I need in my install and uninstall targets in a Makefile for an OCaml library in order to make it play nicely with the rest of the installation, work seamlessly with ocamlfind and so on? Basically to be a "good citizen". I am not interested in GODI at the present time. Thanks!

Answer 1

META files for ocamlfind are easy to write (basically, look for a META in another ocaml project you know¹, copy it and make the corresponding changes), and they will give you ocamlfind integration, with in particular easy support for post-build installation and desinstallation (using ocamlfind install and ocamlfind remove). You should begin with that.

¹: for example I take inspiration from batteries's META.

The building part of the Makefile is more tricky, their are numerous solutions (OCamlMakefile, OMake, ocamlbuild, plain Makefile, etc.) with varying strenghts and weaknesses. If you project is simple enough I would recommend ocamlbuild that takes care of a lot of the dependency tracking by itself.

You may also use Oasis, which is a relatively new tools that builds on ocamlbuild and ocamlfind and seeks to provide a unified configuration file for pre-build configuration and various building and deployment (of your program, your software libraries if any, accompanying data or documentation...). It's not yet a mature project (and its little brother Oasis-DB isn't released yet), but I encourage you to give it a try if you have time. It's a bit more complex than META, as it does more in the end, so building the META first is still a good step.

Finally, you said you weren't interested in Godi (Godi is a very good system, and in some cases (eg. BSD etc.) it's a premium choice to have a good OCaml installation), but in case you may still be interested in Godiva, a tool to help the building of GODI packages. I have never used it myself, though.

Answer 2

I don't use makefiles but ocamlbuild and a shell script to install the software I distribute. Debian people did packages for my software with these scripts without problems. So you may want to check them out since they correspond to some of their requirements (e.g. separate targets for byte and native code).

You may also want to have a look to their packaging policy, though I don't know if this document is still up to date.

Don't forget to add a META file for ocamlfind. And you may also want to include an _oasis file for the upcoming oasis-db project (not yet done in the software I distribute).