Re: [Caml-list] Absolute path in the module system

[Gabriel Scherer <gabriel.scherer@gmail.com>]

As far as I know, the answer is that you can't do that. In fact I
don't even know how you would do that: there is a tension between
powerful naming constructs and stability of references, and I don't
know how you would provide global references in a satisfying way.

This is a classic problem of hygienic macro systems. They are supposed
to protect two different aspects of bound identifiers "hygiene":
- new definition inside macros do not shadow identifiers in scope at
macro invocation/expansion time (it is possible, but not simple, to
emulate this property with careful preservation of scope during
macro-expansion)
- identifiers referenced by macro definitions are not shadowed by
identifier added in scope after that, before macro
invocation/expansion time; this corresponds to your question and I
don't think how you would solve that with a static expansion scheme.

If I remember correctly, the solution of hygienic macro systems is, in
effect, to do a preprocessing step of the pre-expansion source, to
enforce the convention that now name is bound twice in the same scope
by appending unique suffixes to identifiers.

On Tue, Dec 4, 2012 at 9:43 PM, bob zhang <bobzhang1988@gmail.com> wrote:
> Dear List,
>     Is there a way to express the absolute module path?
>     For example,
>        Pervasives.(+) --> actually I want it to be absolute Pervasives
> module, not shadowed by any 'open' statements?
>     Is there a way to do that? if not, is there any deep reason for
> not doing this?
>
> Thanks
>
> --
> Regards
> -- Bob
>
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