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[Anders Logg <logg@xxxxxxxxx>]

I need some advice on how to implement the XML parsing for
MeshDomains. I have this:

<mesh>
  <domains dim="3">
    <mesh_value_collection type="uint" dim="0" />
      stuff
    </mesh_value_collection>
    <mesh_value_collection type="uint" dim="1" />
      stuff
    </mesh_value_collection>
    <mesh_value_collection type="uint" dim="2" />
      stuff
    </mesh_value_collection>
  </domains>
</mesh>

The parsing of MeshValueCollection is implemented in
XMLMeshValueCollection.cpp and I want to reuse that inside
XMLMesh.cpp.

So I've tried something like this:

  // Check if we have any domains
  const pugi::xml_node xml_domains = mesh_node.child("domains");
  if (!xml_domains)
    return;

  // Iterate over data
  for (pugi::xml_node_iterator it = xml_domains.begin();
       it != xml_domains.end(); ++it)
  {
    // Check that node is <mesh_value_collection>
    const std::string node_name = it->name();
    if (node_name != "mesh_value_collection")
      error("Expecting XML node <mesh_value_collection> but got
      <%s>.",
            node_name.c_str());

    // Get attributes
    const std::string type = it->attribute("type").value();
    const uint dim = it->attribute("dim").as_uint();

    // Check that the type is uint
    if (type != "uint")
    {
      dolfin_error("XMLMesh.cpp",
                   "read DOLFIN mesh from XML file",
                   "Mesh domains must be marked as uint, not %s",
                   type.c_str());
    }

    // Read MeshValueCollection
    XMLMeshValueCollection::read(domains.markers(dim), type, *it);
  }

The problem here is that the node *it sent to XMLMeshValueCollection
is already the node for the MeshValueCollection but that parser
expects to get the parent node. But I can't really send it the parent
node since the parent may have more than one child.

Any ideas?

--
Anders