How to achieve this camlp4 syntax extension

How to achieve this camlp4 syntax extension

[Conglun Yao]

Dear all,

I tried to achieve the following syntax extension, but failed.

Add expression .[ ] after a module name, inside .[ ] I want to refer
to the specified module, like

let _ = M1.M2.[ here is my syntax,  using M1.M2 module ]

Here is my attempt (failed)

EXTEND Gram

GLOBAL: expr;

expr: LEVEL "top"[
[ e1 = module_longident; ".";  "[";  (*t = test_syntax;*)  "]" ->
  <:expr< $id:e1$ test >>
]];

END

Different kinds of error happened, when trying to use it.

Even the ordinary expression:  List.length [1; 2;3 ],  failed.  'List'
is parsed as module_longident, try to match the rule I defined.

Thanks for any help.

Conglun

Re: [Caml-list] How to achieve this camlp4 syntax extension

[Jérémie Dimino]

Conglun Yao wrote:
> I tried to achieve the following syntax extension, but failed.
> 
> Add expression .[ ] after a module name, inside .[ ] I want to refer
> to the specified module, like
> 
> let _ = M1.M2.[ here is my syntax,  using M1.M2 module ]

You should have a look at delimited overloading:

  http://pa-do.forge.ocamlcore.org/

It defines the same kind of syntax extension.

Cheers,
Jérémie

Re: [Caml-list] How to achieve this camlp4 syntax extension

[David Teller]

   Hi,
 I'm not going to quite answer your question yet -- I'd need to check
the source of Camlp4 for this. However, I can point out that what you're
trying to do looks very much like pa_open, by Alain Frisch.

let _ = open M1.M2 in e

will execute [e] using module [M1.M2].

Cheers,
 David

On Thu, 2009-04-02 at 12:42 +0100, Conglun Yao wrote:
> Dear all,
> 
> I tried to achieve the following syntax extension, but failed.
> 
> Add expression .[ ] after a module name, inside .[ ] I want to refer
> to the specified module, like
> 
> let _ = M1.M2.[ here is my syntax,  using M1.M2 module ]
> 
> Here is my attempt (failed)
> 
> EXTEND Gram
> 
> GLOBAL: expr;
> 
> expr: LEVEL "top"[
> [ e1 = module_longident; ".";  "[";  (*t = test_syntax;*)  "]" ->
>   <:expr< $id:e1$ test >>
> ]];
> 
> END
> 
> Different kinds of error happened, when trying to use it.
> 
> Even the ordinary expression:  List.length [1; 2;3 ],  failed.  'List'
> is parsed as module_longident, try to match the rule I defined.
> 
> Thanks for any help.
> 
> Conglun
> 
> _______________________________________________
> Caml-list mailing list. Subscription management:
> http://yquem.inria.fr/cgi-bin/mailman/listinfo/caml-list
> Archives: http://caml.inria.fr
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> Bug reports: http://caml.inria.fr/bin/caml-bugs
> 

Re: [Caml-list] How to achieve this camlp4 syntax extension

[Conglun Yao]

David and Jérémie,

Thanks for your guys quick response.

It seems I get idea how to achieve it.  pa_do and pa_open are useful!

It's a pity I viewed the code of pa_infix before, but never noticed it
was part of a project.

Conglun

On Thu, Apr 2, 2009 at 1:40 PM, David Teller
<David.Teller@univ-orleans.fr> wrote:
>   Hi,
>  I'm not going to quite answer your question yet -- I'd need to check
> the source of Camlp4 for this. However, I can point out that what you're
> trying to do looks very much like pa_open, by Alain Frisch.
>
> let _ = open M1.M2 in e
>
> will execute [e] using module [M1.M2].
>
> Cheers,
>  David
>
> On Thu, 2009-04-02 at 12:42 +0100, Conglun Yao wrote:
>> Dear all,
>>
>> I tried to achieve the following syntax extension, but failed.
>>
>> Add expression .[ ] after a module name, inside .[ ] I want to refer
>> to the specified module, like
>>
>> let _ = M1.M2.[ here is my syntax,  using M1.M2 module ]
>>
>> Here is my attempt (failed)
>>
>> EXTEND Gram
>>
>> GLOBAL: expr;
>>
>> expr: LEVEL "top"[
>> [ e1 = module_longident; ".";  "[";  (*t = test_syntax;*)  "]" ->
>>   <:expr< $id:e1$ test >>
>> ]];
>>
>> END
>>
>> Different kinds of error happened, when trying to use it.
>>
>> Even the ordinary expression:  List.length [1; 2;3 ],  failed.  'List'
>> is parsed as module_longident, try to match the rule I defined.
>>
>> Thanks for any help.
>>
>> Conglun
>>
>> _______________________________________________
>> Caml-list mailing list. Subscription management:
>> http://yquem.inria.fr/cgi-bin/mailman/listinfo/caml-list
>> Archives: http://caml.inria.fr
>> Beginner's list: http://groups.yahoo.com/group/ocaml_beginners
>> Bug reports: http://caml.inria.fr/bin/caml-bugs
>>
>
>

Re: How to achieve this camlp4 syntax extension

[Zheng Li]

On 4/2/2009 1:42 PM, Conglun Yao wrote:
>
> Different kinds of error happened, when trying to use it.
>
> Even the ordinary expression:  List.length [1; 2;3 ],  failed.  'List'
> is parsed as module_longident, try to match the rule I defined.
>
> Thanks for any help.
>
> Conglun

You may have a look at the source code of my pa_scope [1]. It deals with 
these issues and support both open scope (via @) and closed scope (via 
.{}, .[], .()). The code is just ~50 lines.

HTH.

[1] http://www.pps.jussieu.fr/~li/software/index.html#pa_scope

--
Zheng

Re: How to achieve this camlp4 syntax extension

[Conglun Yao]

Nice code!!!   Thank you very much.

I'm trying to get the Module name, then used in my syntax extension.

ModuleName.[ my extension ]

It's really a great idea to perform checking in the rule definition.

Conglun

On Thu, Apr 2, 2009 at 2:00 PM, Zheng Li <zheng_li@users.sourceforge.net> wrote:
> On 4/2/2009 1:42 PM, Conglun Yao wrote:
>>
>> Different kinds of error happened, when trying to use it.
>>
>> Even the ordinary expression:  List.length [1; 2;3 ],  failed.  'List'
>> is parsed as module_longident, try to match the rule I defined.
>>
>> Thanks for any help.
>>
>> Conglun
>
> You may have a look at the source code of my pa_scope [1]. It deals with
> these issues and support both open scope (via @) and closed scope (via .{},
> .[], .()). The code is just ~50 lines.
>
> HTH.
>
> [1] http://www.pps.jussieu.fr/~li/software/index.html#pa_scope
>
> --
> Zheng
>
>
>
>
>
>
>

Re: [Caml-list] Re: How to achieve this camlp4 syntax extension

[Christophe TROESTLER]

> On 4/2/2009 1:42 PM, Conglun Yao wrote:
>>
>> Different kinds of error happened, when trying to use it.
>>
>> Even the ordinary expression:  List.length [1; 2;3 ],  failed.  'List'
>> is parsed as module_longident, try to match the rule I defined.

Not sure whether you are still looking for a solution to this but, as
it was not possible to use theses constructions together with pa_do
(same grammar rule to modify), I added hooks so you can provide your
own functions for them.  E.g.,

val module_square_brackets : (module_longident -> Loc.t -> expr -> expr) ref

allows you to replace [M.[ e ]] by [!module_square_brackets m _loc e]
where [m] is the internal representation of [M] and [_loc] is the
location of the whole expression [M.[ e ]].

This is available in the last version of delimited overloading
(downloadable at http://pa-do.forge.ocamlcore.org/ ).

Hope it helps,
ChriS