Ocamlbuild override the default options

Question

My installation of OCaml does not recognize #!, therefore camlp4o cannot be ran standalone. It must be invoked as "ocamlrun camlp4o".

I try to add a flag in the plugin. But the new flag is simply added to the existing flag.

The result is that ocamlbuild will invoke the compiler with

"-pp camlp4o ocamlrun camlp4o".

A working workaround is to introduce a new tag 'my_camlp4o'. However, the documentation of ocamlbuild did mention the capability of 'overriding' defaults. It seems ocamlc, ocamlopt can be overridden. But can we override camlp4o? Can it be done in plugins?

what is the command that you want ocamlbuild to execute? – nlucaroni Feb 28 '13 at 23:26 — nlucaroni, Feb 28 '13 at 23:26

score 2 · Answer 1 · answered Mar 01 '13 at 09:49

There is support for changing defaults in Ocamlbuild, through the -ocamlc <command>, -ocamldep <command> etc. command-line options. Unfortunately, camlp4 is currently not part of the set of customizable commands. Could you please use the issue tracker to request this feature?

(In the meantime I recommend a workaround, eg. you replace the ocamlrun executable in your PATH by an executable script that does the right thing.)

Edit

Another workaround is to do all your compilation through ocamlfind, which has support for overriding the camlp4 command (see the documentation), and can be used as a basis for all ocamlbuild command with the -use-ocamlfind option. Unfortunately, ocamlfind itself only supports preprocessing at compile-time (when invoking the actual compiler), not stand-alone source-to-source processing, so that may not cover your own use case.

Thanks a lot. I will request this feature. – Zhi Han Mar 19 '13 at 15:44 — Zhi Han, Mar 19 '13 at 15:44

Ocamlbuild override the default options

1 Answers1