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/libgui/src/workspace-model.h
+++ b/libgui/src/workspace-model.h
@@ -1,5 +1,6 @@
 /*
 
+Copyright (C) 2013 John W. Eaton
 Copyright (C) 2011-2012 Jacob Dawid
 
 This file is part of Octave.
@@ -20,15 +21,13 @@
 
 */
 
-#ifndef WORKSPACEMODEL_H
-#define WORKSPACEMODEL_H
+#if !defined (workspace_model_h)
+#define workspace_model_h 1
 
-// Qt includes
 #include <QAbstractItemModel>
 #include <QVector>
 #include <QSemaphore>
-
-#include "symbol-information.h"
+#include <QStringList>
 
 class tree_item
 {
@@ -114,35 +113,64 @@
 {
   Q_OBJECT
 
-  public:
+public:
+
   workspace_model (QObject *parent = 0);
-  ~workspace_model ();
+
+  ~workspace_model (void);
 
   QVariant data (const QModelIndex &index, int role) const;
+
   Qt::ItemFlags flags (const QModelIndex &index) const;
+
   QVariant headerData (int section, Qt::Orientation orientation,
                        int role = Qt::DisplayRole) const;
+
   QModelIndex index (int row, int column,
                      const QModelIndex &parent = QModelIndex ()) const;
+
   QModelIndex parent (const QModelIndex &index) const;
+
   int rowCount (const QModelIndex &parent = QModelIndex ()) const;
+
   int columnCount (const QModelIndex &parent = QModelIndex ()) const;
 
   void insert_top_level_item (int at, tree_item *treeItem);
+
   tree_item *top_level_item (int at);
 
-  void update_workspace_callback (void);
-
 public slots:
-  void request_update_workspace ();
+
+  void set_workspace (const QString& scopes,
+                      const QStringList& symbols,
+                      const QStringList& class_names,
+                      const QStringList& dimensions,
+                      const QStringList& values);
+
+  void clear_workspace (void);
 
 signals:
-  void model_changed ();
+
+  void model_changed (void);
 
 private:
 
-  /** Stores the current symbol information. */
-  QList <symbol_information> _symbol_information;
+  void clear_data (void);
+
+  void clear_tree (void);
+
+  void update_tree (void);
+
+  void append_tree (QChar scope, const QString& symbol,
+                    const QString& class_name, const QString& dimension,
+                    const QString& value);
+
+  QString _scopes;
+  QStringList _symbols;
+  QStringList _class_names;
+  QStringList _dimensions;
+  QStringList _values;
+
   tree_item *_rootItem;
 };