Re: [Caml-list] OCamlJava opam packages troubles

[Jeremy Yallop <yallop@gmail.com>]

On Sat, Jul 18, 2015 at 9:36 PM, Kenneth Adam Miller
<kennethadammiller@gmail.com> wrote:
> There are duplicate ocamlfind specific opam packages:
>
> opam search ocamlfind
> ...
> ocamlfind-ocj             --  A library manager for OCaml
> ocj-ocamlfind             --  A library manager for OCaml

It appears that ocj-ocamlfind is the one to use, since it corresponds
to a much more recent version than ocamlfind-ocj:

   $ opam show ocamlfind-ocj | grep version
                version: 1.4.0
      installed-version:
      available-version: 1.4.0
   $ opam show ocj-ocamlfind | grep version
                version: 1.5.5
      installed-version:
      available-version: 1.5.5

> I can't continue development using ocamljava until I can install that
> package. I don't know how to continue hunting this error. Basically, the
> library that I'm developing uses -package bytes in the command line, so I
> presume that base.bytes is the opam package that it's talking about.

If you have ocj-ocamlfind installed then I don't think you need
base-bytes as well, since ocj-ocamlfind automatically installs the
bytes package.  (There are two notions of "package" here:
ocamlfind/findlib packages, such as "bytes", which are specified with
the "-package" flag to ocamlfind, and OPAM packages, such as
"base-bytes".  There's not always a one-to-one correspondence between
the two.)

You can check whether the bytes findlib package is available by
running the following command:

   ocamlfind query bytes

Here's how you might build and run a simple program using OCaml-Java,
ocj-ocamlfind and the bytes package:

   $ cat test_bytes.ml
   let () =
     let name = Sys.argv.(0) in
     Printf.printf "%s (length %d)\n" name (Bytes.length name)
   $ ocamlfind java -o test_bytes.jar -package bytes test_bytes.ml
   $ java -jar ./test_bytes.jar
   /tmp/test_bytes.jar (length 19)

Kind regards,

Jeremy.