class Nokogiri::XML::Namespace

def wrap(document, node_struct)
  if node_struct.is_a?(FFI::Pointer)
    # cast native pointers up into a node cstruct
    return nil if node_struct.null?
    node_struct = LibXML::XmlNs.new(node_struct) 
  end
  ruby_node = node_struct.ruby_node
  return ruby_node unless ruby_node.nil?
  ns = Nokogiri::XML::Namespace.allocate
  ns.document = document.ruby_doc
  ns.cstruct = node_struct
  ns.cstruct.ruby_node = ns
  cache = ns.document.instance_variable_get(:@node_cache)
  cache << ns
  ns
end