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Date: -- (:)
From: Pietro Abate <Pietro.Abate@a...>
Subject: Re: [Caml-list] camlp4 help
On Mon, Jul 18, 2005 at 12:12:27PM +0200, Hendrik Tews wrote:
> See "More Power for Camlp4 recursive descent parsing" in 
> http://wwwtcs.inf.tu-dresden.de/~tews/ocamlp4/camlp4-undoc.html

Inspired from your page I'm trying to mix regular expression
and streams... below there's a bit of code to parsa entry of the form

TEST ------ END

where you can have an arbitray ( > 1) number of dashes.

However, for some reasons, it doesn't work as expected. The function test
correctly recognizes the string "-----" but then I get a Stream.Error from
nowhere ( guess from Grammar.Entry.of_parser ) and the parsin fails...

what am I doing wrong ?

:)
p

------------
(*pp camlp4o -I . pa_extend.cmo q_MLast.cmo *)

let (=~) s re = Str.string_match (Str.regexp re) s 0;;

let test rex strm =
    match Stream.peek strm with
    | Some(_,s) when s =~ rex -> print_endline "!!!!" ; ()
    | _ -> raise Stream.Failure
;;

let test_sep_dash =
  Grammar.Entry.of_parser Pcaml.gram "test_sep_dash" ( test "-+" )
;;

EXTEND
GLOBAL: Pcaml.str_item ;
    Pcaml.str_item: [[
        "TEST"; test_sep_dash; "END" -> <:str_item< value ii = "!!!!" >>
    ]];
END
-------------

#ocamlfind ocamlc -package str -c -pp "camlp4o -I . pa_extend.cmo q_MLast.cmo " -I /usr/lib/ocaml/3.08.3/camlp4 te.ml

#camlp4o /usr/lib/ocaml/3.08.3/str.cma ./te.cmo pr_o.cmo oo.ml
!!!!
File "oo.ml", line 2, characters 5-13:
Parse error: [test_sep_dash] expected after 'TEST' (in [str_item])
Uncaught exception: Stream.Error("[test_sep_dash] expected after 'TEST' (in [str_item])")

-- 
++ Blog: http://blog.rsise.anu.edu.au/?q=pietro
++ 
++ "All great truths begin as blasphemies." -George Bernard Shaw
++ Please avoid sending me Word or PowerPoint attachments.
   See http://www.fsf.org/philosophy/no-word-attachments.html