Re: [O] ocaml babel no longer works?

[Alan Schmitt]

Hello,

Eric Schulte writes:

> Thanks for looking into this.  I've applied a patch to ob-ocaml.el which
> should handle the two different tuareg execution functions.

Thanks a lot.

About the thing "getting stuck", I made some progress. My error was that
I did not add ";;" at the end of my ocaml phrase, which resulted in an
error in the toplevel:

#+begin_quote
        Objective Caml version 3.12.1

# let x = 2 in x
"org-babel-ocaml-eoe";;
  Characters 13-14:
  let x = 2 in x
               ^
Error: This expression is not a function; it cannot be applied
#+end_quote

As you see, it's trying to apply the 'x' to the "oeo" thing. My guess is
that babel waits until seeing this special string before sending the
result back. By the way, this allows for some fun things, like this:

#+BEGIN_SRC ocaml
let f x = () in f
#+END_SRC

make babel stuck because the interpreter is in this state:

#+begin_quote
# let f x = () in f
"org-babel-ocaml-eoe";;
  - : unit = ()
#+end_quote

So I have a suggestion and two feature requests.

The suggestion: instead of appending '"org-babel-ocaml-eoe";;' to the
code, how simply put ';;' (which will make sure everything is flushed)
then detect the toplevel is done by seeing the string '# ' at the
beginning of the line? Would there be an issue with the fact that this
line does not have a newline? If so, an alternative suggestion would be
to use the longer ';; "org-babel-ocaml-eoe";;' which makes sure the
phrase in the input won't interact with the marker.

The first feature requests: if there is an error, could it be parsed?
(It probably always start with 'Error: '). Then the error could be put
in the result block, instead of waiting for the marker that will never
appear.

The second feature request: I want to use this for my ocaml lab classes
(I'm thinking of giving them an org file they have to complete by
writing the caml code). Could it be possible to have an option for the
full output of the compiler (and not just the result) to be printed? I
see it does it when it does not recognize the type of the output. So I
guess such an option would be applied to either
org-babel-ocaml-parse-output or the place where it's called.

Thanks a lot for any suggestion as how to implement this. I think I see
how to do the second one (except I don't know how to add a configuration
variable to toggle it). I have no idea about the first one, though.

Alan