You can try to compile and run the hello_world example of ocaml_plugin:
https://github.com/janestreet/ocaml_plugin/blob/master/hello_world

It has a Plugin_intf module to specify the type of module expected from
loaded file. For you, it should probably be:

module type S = sig
  val equal : ('a * 'a) -> bool
end

Then you can use Ocaml_compiler module to dynamically load modules with
this signature as demonstrated in run.ml


On Mon, Feb 24, 2014 at 4:24 AM, Matej Kosik <
5764c029b688c1c0d24a2e97cd764f@gmail.com> wrote:

> On 23/02/14 13:12, Tianyi Cui wrote:
> > If you know the type of this string in advance, you can do so with
> ocaml_plugin: https://github.com/janestreet/ocaml_plugin
>
> Hm, imagine that the expected type is:
>
>         'a * 'a -> bool
>
> Now, if user provides a string, say:
>
>         "fun (a,b) -> a = b"
>
> how can I convert that string to Ocaml value of the above type (like how
> toplevel does it)?
>
> Is this something ocaml_plugin is able to do for me? I've failed to figure
> out the trick.
>
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