use signal/slot for updating workspace instead of using event listener * main-window.h, main-window.cc: Clean up list of include files. (main_window::prepare_to_exit): Rename from prepare_to_quit. Change all uses. (main_window::update_workspace): Delete. (main_window::construct): Don't connect _octave_qt_event_listener:update_workspace_signal to main_window::update_workspace. (main_window::construct_octave_qt_link): Connect _octave_qt_link::set_workspace_signal to _workspace_model::set_workspace. Connect _octave_qt_link::clear_workspace_signal to _workspace_model::clear_workspace. * symbol-information.h, symbol-information.cc: Delete * libgui/src/module.mk (noinst_HEADERS, src_libgui_src_la_SOURCES): Remove them from the lists. * octave-qt-link.h, octave-qt-link.cc: Don't use symbol_information to store workspace info. (octave_qt_link::do_update_workspace): Delete. (octave_qt_link::do_set_workspace, octave_qt_link::do_clear_workspace): New functions. (octave_qt_link::do_pre_input_event): Don't call do_update_workspace. (octave_qt_link::set_workspace_signal, octave_qt_link::clear_workspace_signal): New signals. * workspace-model.h, workspace-model.cc: Don't use symbol_information to store workspace info. Accept workspace info through a signal/slot combination, not by asking the symbol table. (workspace_model::request_update_workspace, (workspace_model::update_workspace_callback): Delete. (workspace_model::set_workspace, workspace_model::clear_workspace, workspace_model::clear_data, workspace_model::clear_tree, workspace_model::update_tree, workspace_model::append_tree): New functions. * workspace-view.h, workspace-view.cc (workspace_view::model_changed): Don't call update_workspace_callback. The model now signals the view when it has changed. * input.cc (octave_base_reader::octave_gets, get_debug_input): Call octave_link::set_workspace just prior to prompting for input. * workspace-element.h: New file. * libinterp/interpfcn/module.mk (INTERPFCN_INC): Include it in the list. * octave-link.cc: Don't include symtab.h. * octave-link.h (octave_link::update_workspace): Delete. (octave_link::set_workspace, octave_link::do_set_workspace, * octave_link::clear_workspace, octave_link::do_clear_workspace): New functions. * symtab.h, symtab.cc (symbol_table::workspace_info, symbol_table::do_workspace_info): New functions. * ov.h (octave_value::short_disp): New function. * ov-base.h, ov-base.cc (octave_base_value::short_disp): New function. * ov-base-scalar.h, ov-base-scalar.cc (octave_base_scalar<ST>::short_disp): New function. * ov-range.h, ov-range.cc (octave_range::short_disp): New function.

--- a/libinterp/interpfcn/symtab.cc	Sat Apr 06 18:08:08 2013 +0100
+++ b/libinterp/interpfcn/symtab.cc	Mon Apr 08 12:01:24 2013 -0400
@@ -1380,6 +1380,41 @@
   return retval;
 }
 
+std::list<workspace_element>
+symbol_table::do_workspace_info (void) const
+{
+  std::list<workspace_element> retval;
+
+  for (table_const_iterator p = table.begin (); p != table.end (); p++)
+    {
+      std::string nm = p->first;
+      symbol_record sr = p->second;
+
+      if (! sr.is_hidden ())
+        {
+          octave_value val = sr.varval ();
+
+          if (val.is_defined ())
+            {
+              dim_vector dv = val.dims ();
+
+              char storage = ' ';
+              if (sr.is_global ())
+                storage = 'g';
+              else if (sr.is_persistent ())
+                storage = 'p';
+
+              workspace_element elt (storage, nm, val.class_name (),
+                                     val.short_disp (), dv.str ());
+
+              retval.push_back (elt);
+            }
+        }
+    }
+
+  return retval;
+}
+
 void
 symbol_table::do_dump (std::ostream& os)
 {