Do not pass negative numbers to item_grid_find_col and item_grid_find_row.

1998-12-02  Miguel de Icaza  <miguel@nuclecu.unam.mx>

	* src/item-cursor.c (item_cursor_autofill_event): Do not pass
	negative numbers to item_grid_find_col and item_grid_find_row.

	* src/item-grid.c (item_grid_find_row, item_grid_find_col): Check
	for possitive numbers. I think the right fix is to accept negative
	numbers and find the column even if the number is negative instead
	of this ugly restriction.

ChangeLog-1999-07-09

+1998-12-02  Miguel de Icaza  <miguel@nuclecu.unam.mx>
+
+	* src/item-cursor.c (item_cursor_autofill_event): Do not pass
+	negative numbers to item_grid_find_col and item_grid_find_row. 
+
+	* src/item-grid.c (item_grid_find_row, item_grid_find_col): Check
+	for possitive numbers. I think the right fix is to accept negative
+	numbers and find the column even if the number is negative instead
+	of this ugly restriction.
+
+1998-11-30  Miguel de Icaza  <miguel@nuclecu.unam.mx>
+
+	* src/sheet.c (cellref_name): Add more space.
+
 1998-12-02  Sebastian Wilhelmi  <wilhelmi@ira.uka.de>
 
 	* src/Makefile.am: make Gnumeric-impl.c dependend on Gnumeric.h to

ChangeLog-2000-02-23

+1998-12-02  Miguel de Icaza  <miguel@nuclecu.unam.mx>
+
+	* src/item-cursor.c (item_cursor_autofill_event): Do not pass
+	negative numbers to item_grid_find_col and item_grid_find_row. 
+
+	* src/item-grid.c (item_grid_find_row, item_grid_find_col): Check
+	for possitive numbers. I think the right fix is to accept negative
+	numbers and find the column even if the number is negative instead
+	of this ugly restriction.
+
+1998-11-30  Miguel de Icaza  <miguel@nuclecu.unam.mx>
+
+	* src/sheet.c (cellref_name): Add more space.
+
 1998-12-02  Sebastian Wilhelmi  <wilhelmi@ira.uka.de>
 
 	* src/Makefile.am: make Gnumeric-impl.c dependend on Gnumeric.h to

OChangeLog-1999-07-09

+1998-12-02  Miguel de Icaza  <miguel@nuclecu.unam.mx>
+
+	* src/item-cursor.c (item_cursor_autofill_event): Do not pass
+	negative numbers to item_grid_find_col and item_grid_find_row. 
+
+	* src/item-grid.c (item_grid_find_row, item_grid_find_col): Check
+	for possitive numbers. I think the right fix is to accept negative
+	numbers and find the column even if the number is negative instead
+	of this ugly restriction.
+
+1998-11-30  Miguel de Icaza  <miguel@nuclecu.unam.mx>
+
+	* src/sheet.c (cellref_name): Add more space.
+
 1998-12-02  Sebastian Wilhelmi  <wilhelmi@ira.uka.de>
 
 	* src/Makefile.am: make Gnumeric-impl.c dependend on Gnumeric.h to

OChangeLog-2000-02-23

+1998-12-02  Miguel de Icaza  <miguel@nuclecu.unam.mx>
+
+	* src/item-cursor.c (item_cursor_autofill_event): Do not pass
+	negative numbers to item_grid_find_col and item_grid_find_row. 
+
+	* src/item-grid.c (item_grid_find_row, item_grid_find_col): Check
+	for possitive numbers. I think the right fix is to accept negative
+	numbers and find the column even if the number is negative instead
+	of this ugly restriction.
+
+1998-11-30  Miguel de Icaza  <miguel@nuclecu.unam.mx>
+
+	* src/sheet.c (cellref_name): Add more space.
+
 1998-12-02  Sebastian Wilhelmi  <wilhelmi@ira.uka.de>
 
 	* src/Makefile.am: make Gnumeric-impl.c dependend on Gnumeric.h to

doc/Design

@@ -173,6 +173,30 @@
 
   </sect1>
 
+  <sect1>
+      <title>Formula storage</title>
+
+      <para>When a formula is encountered, Gnumeric parses the formula
+      into a tree structure.  The tree structure is later used to
+      evaluate the expression at a given location (each cordinate in a
+      cell references is stored as either an absolute reference or a
+      relative reference to the cell position).</para>
+
+      <para>To speed up formula duplication, Gnumeric reference counts
+      the parsed expression, this allow for quick duplication of
+      expressions.  It should be noted that some file formats (the
+      Excel file format) uses formula references, which can preserve
+      the memory saving features of reference counting.</para>
+      
+      <para>Currently Gnumeric does not provide any way to keep these
+      references, a possible scheme for saving correctly these cells
+      would be to keep in a special list any formula being saved that
+      has a reference count bigger than one and keep track of these
+      duplicates and generate formula references in the output file
+      rather than outputing the actual formula.
+      <para>
+  </sect1>
+
   <sect1>
       <title>Resource management</title>
       

doc/developer/Design

@@ -173,6 +173,30 @@
 
   </sect1>
 
+  <sect1>
+      <title>Formula storage</title>
+
+      <para>When a formula is encountered, Gnumeric parses the formula
+      into a tree structure.  The tree structure is later used to
+      evaluate the expression at a given location (each cordinate in a
+      cell references is stored as either an absolute reference or a
+      relative reference to the cell position).</para>
+
+      <para>To speed up formula duplication, Gnumeric reference counts
+      the parsed expression, this allow for quick duplication of
+      expressions.  It should be noted that some file formats (the
+      Excel file format) uses formula references, which can preserve
+      the memory saving features of reference counting.</para>
+      
+      <para>Currently Gnumeric does not provide any way to keep these
+      references, a possible scheme for saving correctly these cells
+      would be to keep in a special list any formula being saved that
+      has a reference count bigger than one and keep track of these
+      duplicates and generate formula references in the output file
+      rather than outputing the actual formula.
+      <para>
+  </sect1>
+
   <sect1>
       <title>Resource management</title>
       

src/item-cursor.c

@@ -709,6 +709,10 @@ item_cursor_autofill_event (GnomeCanvasItem *item, GdkEvent *event)
 
 	case GDK_MOTION_NOTIFY:
 		gnome_canvas_w2c (canvas, event->button.x, event->button.y, &x, &y);
+		if (x < 0)
+			x = 0;
+		if (y < 0)
+			y = 0;
 		col = item_grid_find_col (item_cursor->item_grid, x, NULL);
 		row = item_grid_find_row (item_cursor->item_grid, y, NULL);
 

src/item-grid.c

@@ -121,6 +121,13 @@ item_grid_find_col (ItemGrid *item_grid, int x, int *col_origin)
 	int col   = item_grid->left_col;
 	int pixel = item_grid->left_offset;
 
+	/*
+	 * FIXME:  This should probably take negative numbers
+	 * as well to provide sliding when moving backwards (look
+	 * in item-cursor.c
+	 */
+	g_return_if_fail (x >= 0);
+
 	do {
 		ColRowInfo *ci = sheet_col_get_info (item_grid->sheet, col);
 		
@@ -143,6 +150,13 @@ item_grid_find_row (ItemGrid *item_grid, int y, int *row_origin)
 	int row   = item_grid->top_row;
 	int pixel = item_grid->top_offset;
 
+	/*
+	 * FIXME:  This should probably take negative numbers
+	 * as well to provide sliding when moving backwards (look
+	 * in item-cursor.c
+	 */
+	g_return_if_fail (y >= 0);
+	
 	do {
 		ColRowInfo *ri = sheet_row_get_info (item_grid->sheet, row);
 		

src/sheet.c

@@ -3151,7 +3151,7 @@ sheet_show_cursor (Sheet *sheet)
 char *
 cellref_name (CellRef *cell_ref, Sheet *eval_sheet, int eval_col, int eval_row)
 {
-	static char buffer [sizeof (long) * 4];
+	static char buffer [sizeof (long) * 4 + 4];
 	char *p = buffer;
 	int col, row;