I'd also add :
- the "formal" part of the manual (Part II) description of module
types : http://caml.inria.fr/pub/docs/manual-ocaml/manual018.html . In
particular the "Type specifications" section is quite informative
imho.
- the module-related chapter of the "UUU book" :
http://caml.inria.fr/pub/docs/u3-ocaml/ocaml-modules.html

If you're interested in theory, you can find an introduction to the ML
Module system theory in the Pierce's book "Advanced topic in Types and
Programming Languages" [1], and a some more advanced papers in the "A
Few Paper On Caml" section of this website :
http://caml.inria.fr/about/papers.en.html

[1] http://books.google.com/books?id=A5ic1MPTvVsC&pg=PA293&dq=pierce+module+ML#v=onepage&q=pierce%20module%20ML&f=false

On Tue, Nov 10, 2009 at 9:31 AM, Pierre-Evariste Dagand
<pedagand@gmail.com> wrote:
> Hi Wouter,
>
>> While I'm familiar with functional programming, I am occasionally puzzled by
>> errors relating to the module system.
>
> That's normal, everyone does, at some point. Especially when you start
> having Parameterized Modules (called Functors in ML) all over the
> place.
>
>> I was wondering if there was a
>> comprehensive overview/tutorial of OCaml's module system.
>
> For a comprehensive source of information, there is the OCaml manual:
>
> http://caml.inria.fr/pub/docs/manual-ocaml/manual004.html
>
> For a tutorial on modules, I would recommend Chapter 14 of "Developing
> Applications With Objective Caml":
>
> http://caml.inria.fr/pub/docs/oreilly-book/html/index.html
>
>
> Hope this helps,
>
>
> --
> Pierre-Evariste DAGAND
> http://perso.eleves.bretagne.ens-cachan.fr/~dagand/
>
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