[Caml-list] Re: ANN: Brand-new BER MetaOCaml for OCaml 4.00.1

[oleg@okmij.org]

Bob Zhang wrote:
> After reading the patch of BER MetaOCaml today, I found that it is not
> too hard to port camlp4/Fan to support metaocaml.

That's a good news! Old camlp4 was once ported to MetaOCaml, but it
took really a lot of effort. 

> I get an install error
> ./build/partial-install.sh: line 25: config/config.sh: No such file or directory
> make: *** [install] Error 1

> After I ignore the error message, the metaocaml toplevel works
> perfectly well.

The error comes about because the Makefile doesn't build
ocamlbuild. To save time during the development metaocaml, I skip
building ocamlbuild (I don't use it myself). I guess I didn't
reactivated it. I will fix this shortly in the metaocaml.bundle.
In the meanwhile, you can do 
        make ocamlbuild.byte
in the main ocaml-4.00.1 tree, followed by make install. This time
there should be no build/partial-install.sh error. ocamlbuild will be
installed. 

>    But if I customized my own toplevel (I used my toplevel as 'ocamlmktop
> -custom -o mocaml')
>    mocaml is bundled with compiler-libs, the toplevel does not work, I get
> the following
>    error message:
>
>    # let spower7 = .! spower7_code;;
>    Error: Reference to undefined global `Runcode'

As Jacques said, you do need to use metaocamlmktop. This is just a
shell script; you can look inside and see what libraries and object
files it uses and link your own toplevel accordingly (the order
libraries and object files matters!)

>   Currently metaocaml does not support native code, but it seems that the
> patch only installs ocamlc, is it possible to get ocamlc.opt installed as
> well? (not the ocamlopt.opt) ocamlbuild is not installed either. It would
> be even nicer that ocamlopt.opt could be installed without supporting
> metaocaml, otherwise I have to switch between different compilers from time
> to time.

Yes, it is possible. It is possible almost immediately but I just had
an idea how to do it much better. If works out it will bring essentially
native metaocaml. I will need time to check it though... Well, better
is the enemy of the good. 

If you want ocamlopt urgently (without
using brackets and escapes) I can make a patch easily -- or tell you one
line to add to one file. Namely, to the file 
asmcomp/cmmgen.ml add at the line 1713 (at the end of the function
emit_constant_field) the following single line:
  | Const_csp_value _  -> assert false

After that, do make ocamlopt followed by make install. You get
ocamlopt that, as a side benefit, understands the let! monadic
notation (which never made it to the official version, but seems quite
handy).