RE: [Caml-list] ocamlfind? how to compile

[David Allsopp <dra-news@metastack.com>]

Mr. Herr wrote:
> Am 12.04.2013 18:19, schrieb David Allsopp:
> > Mr. Herr wrote:
> >> I did not understand how the helpers for compilation are supposed to
> work.
> >>
> >> For example I have a script that executes external programs, and
> >> needs the Unix module.
> >>
> >> For script execution I have in the top of my script: #load
> >> "unix.cma";;
> > Good "trick" for findlib is to add:
> > 	#use "topfind"
> > to ~/.ocamlinit (create it, if necessary) and then in future toploops
> you just say
> > 	#require "unix";;
> > instead. Useful when you start using packages which depend on other
> packages...
> >
> 
> First try:
> 
> I added topfind to .ocamlinit, and in the interactive toplevel I see the
> startup info, and I can enter [ #require "unix";; ], but when I put [
> #require "unix";; ] into my .ml file I get a syntax error on it:

If you want to use findlib toploop directives in an ML file (i.e. invoked using ocaml Foo.ml) then you have to put [#use "topfind";;] into the .ml file as well (which is obviously only worthwhile if you have a lot of things to load). The script, presumably, /usr/lib64/ocaml/topfind contains the instructions necessary to make #require and so on work and .ocamlinit is only read if you invoke an interactive toploop (i.e. it's not read when you supply an input file on the command line).

> str@suse122-intel:~/Ocaml/ml> ocaml unix2_exec.ml ls -l b\* Unknown
> directive `require'.
> 
> Same error on compile with ocamlc. Sorry, I don't see how this is supposed
> to work.

It was just a tip for using findlib in the toploop! Note that all directives (anything beginning with a '#') are explicitly for ocaml and never ocamlc/ocamlopt.


David