Redo portions of file editor to use more signals/slots rather than casting. * file-editor-tab.cc, file-editor-tab.h (file_editor_tab::~file_editor_tab): Add. Delete lexer to prevent memory leak. Delete _edit_area to prevent memory leak. (file_editor_tab::conditional_close): Add. Simple slot that uses QWidget pointer as unique ID, not for function call. (file_editor_tab::file_name_query): Add. Simple slot that signals file name to whomever is connected. (file_editor_tab::find, file_editor_tab : public QWidget): Removed use of exec() and keep a pointer to the find_dialog as a member. Toggle hide()/show() via a connected slot to toggle visibility as desired. * file-editor.cc, file-editor.h, file-editor-tab.cc file-editor-tab.h (file_editor : public file_editor_interface, file_editor_tab : public QWidget, file_editor_tab::file_editor_tab, file_editor_tab::closeEvent, file_editor_tab::load_file, file_editor_tab::new_file, file_editor_tab::run_file): Remove _file_editor pointer member from file_editor_tab and rid file_editor::get_main_window from file_editor. There should be no need for such information about higher-level hierarchy inside lower-level objects. (file_editor::request_open_file, file_editor_tab::open_file): Move QFileDialog to file_editor::request_open_file and delete file_editor_tab::open_file since most of the remaining functionality is in file_editor_tab::load_file. (file_editor::active_editor_tab): Deleted. (file_editor::fetab_change_request, file_editor_tab::change_editor_state): Added to initiate a request for the editor tab to change focus. (file_editor_tab::editor_state_changed): Added arguments to pass the copy status and the directory path so that editor doesn't have to call functions for such information. (file_editor::handle_editor_state_changed): Add copying directory of the file_editor_tab to the current editing directory. (file_editor::check_conflict_save, file_editor_tab::editor_check_conflict_save, file_editor_tab::save_file_as, file_editor_tab::handle_save_file_as_answer): Moved a portion of the save-file-as dialog mechanism to the file_editor where all file names can be obtained to check for conflict with already open files. The new signal indicates to the editor that a name check be done, and in turn the editor signals the tab to save the file. * main-window.cc, file-editor.cc, file-editor.h, file-editor-interface.h (file_editor::terminal, file_editor : public file_editor_interface, file_editor_interface : public QDockWidget): Since file_editor_tab no longer looks up to main_window, remove _main_window and _terminal from file_editor and file_editor_interface, as well as file_editor::terminal. * file-editor-tab.cc (file_editor_tab::file_has_changed): Make the dialog boxes non-modal and use slots to handle user answers. (file_editor_tab::closeEvent): Remove portion that accesses upper hierarchy member functions, can find better approaches. (file_editor_tab::file_editor_tab): Make there no parent for QsciScintilla so that window modality can be set to individual editor. * file-editor-tab.cc, file-editor.cc (file_editor_tab::load_file): Use show() member rather than exec() and set modality to window so that rest of application may function. Return a QString with message rather than a boolean. * file-editor-tab.cc, (file_editor_tab::file_has_changed): Remove static variable alreadyAsking. Multiple file_editor_tabs are using this code so do not want to block recognition of multiple file having changed on disk (bug #37406). Instead, simply stop tracking via the file watcher. (file_editor_tab::save_file, file_editor_tab::save_file_as, file_editor_tab::handle_save_file_as_answer, file_editor_tab::handle_save_file_as_answer_close): Added a remove_on_success variable. Changed the QFileDialog to WindowModal and created slots to handle file selected signal and finished signal. Signal/slot connects vary based upon remove_on_success setting. (file_editor_tab::check_file_modified): Changed the QFileDialog to NonModal and attach some slots. Editor tab can't be parent in case deleted, so use read-only state of the editor area. * file-editor-tab.h (file_editor_tab : public QWidget): New signals for file_editor for tab and file name management. (file_editor_tab::get_file_name): Delete. * file-editor.h (file_editor : public file_editor_interface): Make QStringList sessionFileNames a member of file_editor so that it can retain data between file_editor_tab signals. Also can be used for checking precense of filenames and prevent opening multiple copies (bug #36869) Added signals for file editor tabs--settings_changed, fetab_close_request, and query_file_name. Three new slots for tab and file name management. * file-editor-interface.h, file-editor.h (file_editor_interface::add_file_editor_tab, file_editor::add_file_editor_tab): Made the text name for the tab an input variable. * file-editor.cc (file_editor::~file_editor): Replace dynamic_cast with simple signal querying all file editor tabs for file names which end up in savedSessionTabs. (file_editor::handle_file_name_changed): Dynamic cast not necessary since QObject and QWidget are compatible. (file_editor::handle_tab_close_request): Replace dynamic_cast with signal to request file_editor_tab with associated tabID tag should close. (file_editor::handle_tab_remove_request): Rename of handle_tab_close_request. Instead of dynamic cast, loop through pointers comparing QWidget* to QObject*, if same tag remove tab via index and also delete which fixes a memory leak. (file_editor::handle_add_filename_to_list): Simple slot that uses append() of the list member functions. (file_editor::notice_settings): Rather than dynamic cast, emit signal for the file_editor_tabs. (file_editor::add_file_editor_tab): New variety of connections for improved flow. (file_editor::request_open_file): Given error messages are made WindowModal, the tab shouldn't be delete if file open is not successful. The file_editor_tab takes care of that. (file_editor::request_open_file): Added check and message box for the requested file already open in editor. For the non-interactive overloaded version, open a message dialog box to tell the user file not found, e.g., could not find file in the settings when launched. (file_editor::request_open_file): Inquire file names and update list before checking for existence of files. Supply empty title to editor tab then have file_editor_tab update name. * file-editor-tab.h, file-editor-tab.cc, file-editor.cc (file_editor_tab::run_file): New signal process_octave_code. (file_editor::add_file_editor_tab): Connect signal process_octave_code to file_editor's parent's slot handle_command_double_clicked.

## Copyright (C) 2008-2012 David Bateman
##
## This file is part of Octave.
##
## Octave is free software; you can redistribute it and/or modify it
## under the terms of the GNU General Public License as published by
## the Free Software Foundation; either version 3 of the License, or (at
## your option) any later version.
##
## Octave is distributed in the hope that it will be useful, but
## WITHOUT ANY WARRANTY; without even the implied warranty of
## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
## General Public License for more details.
##
## You should have received a copy of the GNU General Public License
## along with Octave; see the file COPYING.  If not, see
## <http://www.gnu.org/licenses/>.

## -*- texinfo -*-
## @deftypefn  {Function File} {} ezplot (@var{f})
## @deftypefnx {Function File} {} ezplot (@var{fx}, @var{fy})
## @deftypefnx {Function File} {} ezplot (@dots{}, @var{dom})
## @deftypefnx {Function File} {} ezplot (@dots{}, @var{n})
## @deftypefnx {Function File} {} ezplot (@var{h}, @dots{})
## @deftypefnx {Function File} {@var{h} =} ezplot (@dots{})
##
## Plot the curve defined by @var{f} in two dimensions.  The function
## @var{f} may be a string, inline function or function handle and can
## have either one or two variables.  If @var{f} has one variable, then
## the function is plotted over the domain @code{-2*pi < @var{x} < 2*pi}
## with 500 points.
##
## If @var{f} has two variables then @code{@var{f}(@var{x},@var{y}) = 0}
## is calculated over the meshed domain @code{-2*pi < @var{x} | @var{y}
## < 2*pi} with 60 by 60 in the mesh.  For example:
##
## @example
## ezplot (@@(@var{x}, @var{y}) @var{x}.^2 - @var{y}.^2 - 1)
## @end example
##
## If two functions are passed as strings, inline functions or function
## handles, then the parametric function
##
## @example
## @group
## @var{x} = @var{fx} (@var{t})
## @var{y} = @var{fy} (@var{t})
## @end group
## @end example
##
## @noindent
## is plotted over the domain @code{-2*pi < @var{t} < 2*pi} with 500
## points.
##
## If @var{dom} is a two element vector, it represents the minimum and maximum
## value of @var{x}, @var{y} and @var{t}.  If it is a four element
## vector, then the minimum and maximum values of @var{x} and @var{t}
## are determined by the first two elements and the minimum and maximum
## of @var{y} by the second pair of elements.
##
## @var{n} is a scalar defining the number of points to use in plotting
## the function.
##
## The optional return value @var{h} is a graphics handle to the created plot.
##
## @seealso{plot, ezplot3}
## @end deftypefn

function retval = ezplot (varargin)

  [h, needusage] = __ezplot__ ("plot", varargin{:});

  if (needusage)
    print_usage ();
  endif

  if (nargout > 0)
    retval = h;
  endif

endfunction


%!demo
%! clf;
%! ezplot (@cos, @sin);

%!demo
%! clf;
%! ezplot ('1/x');

%!demo
%! clf;
%! ezplot (inline ('x^2 - y^2 = 1'));