new (Nokogiri::XML::ProcessingInstruction)

    /*
     * call-seq:
     *  new(document, name, content)
     *
     * Create a new ProcessingInstruction element on the +document+ with +name+
     * and +content+
     */
    static VALUE new(int argc, VALUE *argv, VALUE klass)
    {
      xmlDocPtr xml_doc;
      VALUE document;
      VALUE name;
      VALUE content;
      VALUE rest;

      rb_scan_args(argc, argv, "3*", &document, &name, &content, &rest);

      Data_Get_Struct(document, xmlDoc, xml_doc);

      xmlNodePtr node = xmlNewDocPI(
          xml_doc,
          (const xmlChar *)StringValuePtr(name),
          (const xmlChar *)StringValuePtr(content)
      );

      NOKOGIRI_ROOT_NODE(node);

      VALUE rb_node = Nokogiri_wrap_xml_node(klass, node);
      rb_funcall2(rb_node, rb_intern("initialize"), argc, argv);

      if(rb_block_given_p()) rb_yield(rb_node);

      return rb_node;
    }