[Ocaml-pxp-users] [repost] Creating a simple document with namespaces

[Richard Jones]

My last query wasn't perhaps focused enough to generate any responses.
I'm finding the PXP API to be very hard to understand, even to do
apparently simple things.

I want to create and print out an XML document with namespaces.  I
don't need validation or DTDs at this point.

Here is my test program:

----------------------------------------------------------------------
(* Namespace test.
 * Compile with:
 * ocamlc -I +pcre -I +equeue -I +netstring -I +netclient -I +pxp-lex-iso88591 -I +pxp-engine str.cma unix.cma pcre.cma equeue.cma netstring.cma netclient.cma pxp_engine.cma pxp_lex_iso88591.cma pxp_lex_link_iso88591.cmo test.ml -o test
 *)

let dtd =
  new Pxp_dtd.dtd Pxp_types.default_config.Pxp_types.warner
    Pxp_types.default_config.Pxp_types.encoding

(* Helper functions for creating element and data nodes. *)

let create_element, create_data =
  let dtd =
    let collect_warnings = Pxp_types.default_config.Pxp_types.warner in
    let rep_encoding = Pxp_types.default_config.Pxp_types.encoding in
    new Pxp_dtd.dtd collect_warnings rep_encoding in

  let exemplar = new Pxp_document.namespace_element_impl
    Pxp_tree_parser.default_extension in

  let create_element name =
    exemplar#create_element ~valcheck:false
      dtd (Pxp_document.T_element name) []
  in
  let create_data data =
    exemplar#create_data dtd data
  in
  create_element, create_data

let () =
  let env = create_element "Envelope" in
  let body = create_element "Body" in
  env#set_nodes [body];
  let call = create_element "hello" in
  body#set_nodes [call];

  let params =
    let id = create_element "id" in
    id#set_nodes [create_data "1"];
    let p1 = create_element "p1" in
    p1#set_nodes [create_data "2"];
    [ id; p1 ] in

  call#set_nodes params;

  let buf = Buffer.create 1024 in
  env#write (`Out_buffer buf) `Enc_utf8;
  let data = Buffer.contents buf in

  print_endline ("XML request = \n" ^ data);
----------------------------------------------------------------------

When run this produces the oblique error message:

Fatal error: exception Pxp_core_types.Method_not_applicable("create_data")

How do I make this work?

Rich.

-- 
Richard Jones, CTO Merjis Ltd.
Merjis - web marketing and technology - http://merjis.com
Team Notepad - intranets and extranets for business - http://team-notepad.com