allow renaming of variables in workspace viewer * main-window.h, main-window.cc (main_window::handle_rename_variable_request): New function. (main_window::construct_octave_qt_link): Connect _workspace_model::rename_variable to main_window::handle_rename_variable_request. (main_window::rename_variable_callback): New function. * octave-qt-link.h, octave-qt-link.cc (octave_qt_link::do_set_workspace, octave_qt_link::set_workspace_signal): New argument, top_level. Change all uses. * octave-link.h, octave-link.cc (octave_link::post_event): Provide two-argument version. (octave_link::set_workspace, octave_link::do_set_workspace): New argument, top_level. Change all uses. * workspace-model.h, workspace-model.cc (workspace_model::flags): Conditionally add Qt::ItemIsEditable to flags. (workspace_model::data): Also return value for column 0 if it is editable. (workspace_model::setData): Handle setting new values. (workspace_model::_top_level): New data member. (workspace_model::set_workspace): New argument, top_level. (workspace_model::rename_variable): New signal. * workspace-view.h, workspace-view.cc (variable_name_editor): New class. (workspace_view::var_name_editor): New data member. (workspace_view::workspace_view): Initialize it. Set var_name_editor as delegate for column 0. (workspace_view::~workspace_view): Delete var_name_editor. (workspace_view::item_double_clicked): Delete. * symtab.h (symbol_table::rename, symbol_table::do_rename, symbol_table::symbol_record::rename): New functions.

--- a/libgui/src/main-window.h
+++ b/libgui/src/main-window.h
@@ -64,6 +64,8 @@
 
 public:
 
+  typedef std::pair <std::string, std::string> name_pair;
+
   main_window (QWidget *parent = 0);
 
   ~main_window (void);
@@ -82,6 +84,8 @@
   void handle_load_workspace_request (void);
   void handle_clear_workspace_request (void);
   void handle_clear_history_request (void);
+  void handle_rename_variable_request (const QString& old_name,
+                                       const QString& new_name);
   void new_file (const QString& commands = QString ());
   void open_file (const QString& file_name = QString ());
   void open_online_documentation_page (void);
@@ -150,6 +154,8 @@
 
   void load_workspace_callback (const std::string& file);
 
+  void rename_variable_callback (const name_pair& names);
+
   void clear_workspace_callback (void);
 
   void clear_history_callback (void);