Re: [Caml-list] A question about custom toplevels

["Jocelyn Sérot" <Jocelyn.SEROT@univ-bpclermont.fr>]

Dear Nicolàs,

Thank for your very clear answer. 
I should have guessed this from the fact that the .cmi files were not available indeed ..

Best wishes

Jocelyn

Le 8 mars 2018 à 15:18, Nicolás Ojeda Bär <nicolas.ojeda.bar@lexifi.com> a écrit :

> Dear Jocely,
> 
> I do not think this is currently possible.
> 
> When you enter a phrase into the toplevel (custom or otherwise), it is
> compiled much the same way as if it had been written in a file and
> passed to ocamlc.
> To do so the compiler needs access to the signature information stored
> in the .cmi files of all referenced modules. This is completely
> independent of whether the code of those modules is linked into the
> toplevel or loaded separately which is what ocamlmktop is about.
> 
> Note that it works the same way even for modules of the stdlib. The
> reason "it just works" in that case is because a flag "-I <stdlibdir>"
> is added implicitly. But if you pass the -nostdlib flag to the
> toplevel, this implicit flag is not added, and the toplevel will not
> be able to find the .cmi files of the stdlib in much the same way in
> cannot find foo.cmi.
> 
> Best wishes,
> Nicolás
> 
> On Thu, Mar 8, 2018 at 9:19 AM, Jocelyn Sérot
> <Jocelyn.Serot@univ-bpclermont.fr> wrote:
>> Hello,
>> 
>> I recently stumbled on a problem and am wondering whether it comes from a
>> misunderstanding or a bad usage.
>> 
>> When a custom toplevel is built using the [ocamlmktop] program, it seems
>> that the modules which are « included » must be present in the path when the
>> so-built toplevel is executed afterwards.
>> 
>> For example, suppose that directory « bar » contains  a file foo.ml, with,
>> let say the definition « let v=100 ».
>> Then, making
>> 
>> ocamlfind ocamlc -c -o foo.cmo foo.ml
>> ocamlfind ocamlc -a -o foo.cma foo.cmo
>> ocamlfind ocamlmktop -o foo.top foo.cma
>> 
>> creates foo.top, which, when executed, behaves has expected.
>> 
>> $ ./foo.top
>>        OCaml version 4.06.0
>> 
>> # Foo.v;;
>> - : int = 100
>> 
>> But, when trying to execute foo.top from another directory, for ex from
>> ../bar, i get the following error :
>> 
>> $ ./bar/foo.top
>>        OCaml version 4.06.0
>> 
>> # Foo.v;;
>> Error: Unbound module Foo
>> 
>> The error disappears if i add option « -I ./bar » when lauching foo.top (or,
>> equivently execute the directive « #directory ./bar »).
>> 
>> Is there a way to build a « self-contained » custom toplevel which could be
>> executed without any explicit reference to the modules it included at
>> creation ?
>> 
>> Jocelyn
>> 
>> ps : i tried the -custom option but, not surprisingly, it does not solve the
>> pb since it only refers to external C code.