[PATCH] option to display formulas

[Martin Sheppard <shepp camtech net au>]

Hi,

This patch adds a menu item which toggles displaying the text of formulas
entered rather than the value they evaluate to. This functionality is
present in Excel and is essential for a particular school maths course here
in South Australia. Ultimately the option should probably go somewhere else
like Excel's Tools->Options dialog, but for the moment the current location
on the view menu seems sendible. It works by setting the rendered text of a
cell to the text of the formula instead of the value of the formula when
the option is switched on. If the option is changed then a recalculation is
triggered to flush the now incorrect rendered value.

Cheers,

Martin Sheppard.



diff -rup gnumeric-0.45-clean/src/cell.c gnumeric-0.45/src/cell.c
---
gnumeric-0.45-clean/src/cell.c	Sat Nov 20 08:29:00 1999
+++
gnumeric-0.45/src/cell.c	Mon Dec 27 13:50:49 1999
@@ -378,7 +378,9 @@
cell_get_formatted_val (Cell *cell, Styl
  * cell_render_value
  * @cell:
The cell whose value needs to be rendered
  *
- * The value of the cell is
formated according to the format style
+ * The value of the cell is
formated according to the format style, but if
+ * formulas are being
displayed then use the text of the formula instead of 
+ * its value.
  */

void
 cell_render_value (Cell *cell)
@@ -398,6 +400,14 @@ cell_render_value
(Cell *cell)
 	}
 
 	str = cell_get_formatted_val (cell, &color);
+	if
(cell->sheet->workbook->display_formulas && cell->parsed_node){
+
ParsePosition pp;
+		char *tmpstr = expr_decode_tree (cell->parsed_node,
+
				 parse_pos_cell (&pp, cell));
+		g_free (str);
+		str = g_strconcat
("=", tmpstr, NULL);
+		g_free (tmpstr);
+	}
 	cell->render_color = color;


 	cell_set_rendered_text (cell, str);
diff -rup
gnumeric-0.45-clean/src/workbook.c gnumeric-0.45/src/workbook.c
---
gnumeric-0.45-clean/src/workbook.c	Sat Dec  4 12:30:11 1999
+++
gnumeric-0.45/src/workbook.c	Mon Dec 27 13:43:43 1999
@@ -752,6 +752,13 @@
zoom_cmd (GtkWidget *widget, Workbook *w
 }
 
 static
void
+toggle_formulas_cmd (GtkWidget *widget, Workbook *wb)
+{
+
wb->display_formulas = !wb->display_formulas;
+	workbook_recalc_all
(wb);
+}
+
+static void
 format_cells_cmd (GtkWidget *widget, Workbook
*wb)
 {
 	Sheet *sheet;
@@ -1005,6 +1012,8 @@ static GnomeUIInfo
workbook_menu_edit []
 static GnomeUIInfo workbook_menu_view [] = {
 	{
GNOME_APP_UI_ITEM, N_("_Zoom..."),
 	  N_("Zoom the spreadsheet in or
out"), zoom_cmd },
+	{ GNOME_APP_UI_ITEM, N_("Toggle _Formulas"),
+
N_("Toggle the display of formulas"), toggle_formulas_cmd },

GNOMEUIINFO_END
 };
 
@@ -2041,6 +2050,7 @@ workbook_new (void)
 	wb =
gtk_type_new (workbook_get_type ());
 	wb->toplevel  = gnome_app_new
("Gnumeric", "Gnumeric");
 	wb->table     = gtk_table_new (0, 0, 0);
+
wb->display_formulas = FALSE;
 
 	gtk_window_set_policy (GTK_WINDOW
(wb->toplevel), 1, 1, 0);
 	sx = MAX (gdk_screen_width  () - 64, 400);
diff
-rup gnumeric-0.45-clean/src/workbook.h gnumeric-0.45/src/workbook.h
---
gnumeric-0.45-clean/src/workbook.h	Sat Dec  4 12:30:11 1999
+++
gnumeric-0.45/src/workbook.h	Mon Dec 27 13:46:59 1999
@@ -111,6 +111,8 @@
struct _Workbook {
 
 	void       *corba_server;
 
+	gboolean
display_formulas; 
+
 	WorkbookPrivate *priv;
 };