Ok, finally got recalculation working as it is supposed to work.

Ok, finally got recalculation working as it is supposed to work.

This piece of code is so clean that it was actually a clean fix :-)

ChangeLog-1999-07-09

+1998-08-11  Miguel de Icaza  <miguel@nuclecu.unam.mx>
+
+	* src/eval.c (workbook_recalc): New recomputation strategy:  We
+	now keep a generation flag for determining whenever a cell value
+	has been recomputed for this generation.  The generation variable
+	is a char.  Everytime we are about to overflow the char, we walk
+	the list of formulas and reset the generation flag.
+
 1998-08-10  Miguel de Icaza  <miguel@nuclecu.unam.mx>
 
 	* src/eval.c (workbook_recalc): Queue computation for cells that

ChangeLog-2000-02-23

+1998-08-11  Miguel de Icaza  <miguel@nuclecu.unam.mx>
+
+	* src/eval.c (workbook_recalc): New recomputation strategy:  We
+	now keep a generation flag for determining whenever a cell value
+	has been recomputed for this generation.  The generation variable
+	is a char.  Everytime we are about to overflow the char, we walk
+	the list of formulas and reset the generation flag.
+
 1998-08-10  Miguel de Icaza  <miguel@nuclecu.unam.mx>
 
 	* src/eval.c (workbook_recalc): Queue computation for cells that

OChangeLog-1999-07-09

+1998-08-11  Miguel de Icaza  <miguel@nuclecu.unam.mx>
+
+	* src/eval.c (workbook_recalc): New recomputation strategy:  We
+	now keep a generation flag for determining whenever a cell value
+	has been recomputed for this generation.  The generation variable
+	is a char.  Everytime we are about to overflow the char, we walk
+	the list of formulas and reset the generation flag.
+
 1998-08-10  Miguel de Icaza  <miguel@nuclecu.unam.mx>
 
 	* src/eval.c (workbook_recalc): Queue computation for cells that

OChangeLog-2000-02-23

+1998-08-11  Miguel de Icaza  <miguel@nuclecu.unam.mx>
+
+	* src/eval.c (workbook_recalc): New recomputation strategy:  We
+	now keep a generation flag for determining whenever a cell value
+	has been recomputed for this generation.  The generation variable
+	is a char.  Everytime we are about to overflow the char, we walk
+	the list of formulas and reset the generation flag.
+
 1998-08-10  Miguel de Icaza  <miguel@nuclecu.unam.mx>
 
 	* src/eval.c (workbook_recalc): Queue computation for cells that

src/cell.h

@@ -48,12 +48,11 @@ typedef struct {
 	int       height;	/* Height of text */
 
 	int       flags;
-	int       iteration;
+	char      generation;
 } Cell;
 
 #define CELL_TEXT_GET(cell) ((cell)->text ? cell->text->str : cell->entered_text->str)
 #define CELL_IS_FORMULA(cell) (cell->entered_text->str [0] == '=')
-#define MAX_ITERATIONS(cell) 1
 
 void        cell_set_text             (Cell *cell, char *text);
 void        cell_set_formula          (Cell *cell, char *text);

src/dependent.c

@@ -23,11 +23,6 @@ cell_eval (Cell *cell)
 
 	g_return_if_fail (cell != NULL);
 
-	if (cell->iteration == MAX_ITERATIONS(cell))
-		return;
-	
-	cell->iteration++;
-
 	if (cell->text)
 		string_unref (cell->text);
 	
@@ -56,7 +51,6 @@ cell_eval (Cell *cell)
 	sheet_redraw_cell_region (cell->sheet,
 				  cell->col->pos, cell->row->pos,
 				  cell->col->pos, cell->row->pos);
-	cell->iteration--;
 }
 
 /*
@@ -322,7 +316,6 @@ search_cell_deps (gpointer key, gpointer value, gpointer closure)
 	for (l = range->cell_list; l; l = l->next){
 		Cell *cell = l->data;
 
-		printf ("Found dependenat: %d, %d\n", cell->col->pos, cell->row->pos);
 		c->list = g_list_prepend (c->list, cell);
 	}
 }
@@ -384,16 +377,48 @@ pick_next_cell_from_queue (Workbook *wb)
 	return cell;
 }
 
+/*
+ * Increments the generation.  Every time the generation is
+ * about to wrap around, we reset all of the cell counters to zero
+ */
+void
+workbook_next_generation (Workbook *wb)
+{
+	if (wb->generation == 255){
+		GList *cell_list = wb->formula_cell_list;
+		
+		for (; cell_list; cell_list = cell_list->next){
+			Cell *cell = cell_list->data;
+
+			cell->generation = 0;
+		}
+		wb->generation = 1;
+	} else
+		wb->generation++;
+}
+
 void
 workbook_recalc (Workbook *wb)
 {
+	int generation;
 	Cell *cell;
-	GList *deps;
+	GList *deps, *l;
+
+	workbook_next_generation (wb);
+	generation = wb->generation;
 	
 	while ((cell = pick_next_cell_from_queue (wb))){
+		cell->generation = generation;
 		cell_eval (cell);
 		deps = cell_get_dependencies (cell->sheet, cell->col->pos, cell->row->pos);
-		if (deps)
-			cell_queue_recalc_list (deps);
+
+		for (l = deps ; l; l = l->next){
+			Cell *one_cell;
+
+			one_cell = l->data;
+			if (one_cell->generation != generation)
+				cell_queue_recalc (one_cell);
+		}
+		g_list_free (deps);
 	}
 }

src/eval.c

@@ -23,11 +23,6 @@ cell_eval (Cell *cell)
 
 	g_return_if_fail (cell != NULL);
 
-	if (cell->iteration == MAX_ITERATIONS(cell))
-		return;
-	
-	cell->iteration++;
-
 	if (cell->text)
 		string_unref (cell->text);
 	
@@ -56,7 +51,6 @@ cell_eval (Cell *cell)
 	sheet_redraw_cell_region (cell->sheet,
 				  cell->col->pos, cell->row->pos,
 				  cell->col->pos, cell->row->pos);
-	cell->iteration--;
 }
 
 /*
@@ -322,7 +316,6 @@ search_cell_deps (gpointer key, gpointer value, gpointer closure)
 	for (l = range->cell_list; l; l = l->next){
 		Cell *cell = l->data;
 
-		printf ("Found dependenat: %d, %d\n", cell->col->pos, cell->row->pos);
 		c->list = g_list_prepend (c->list, cell);
 	}
 }
@@ -384,16 +377,48 @@ pick_next_cell_from_queue (Workbook *wb)
 	return cell;
 }
 
+/*
+ * Increments the generation.  Every time the generation is
+ * about to wrap around, we reset all of the cell counters to zero
+ */
+void
+workbook_next_generation (Workbook *wb)
+{
+	if (wb->generation == 255){
+		GList *cell_list = wb->formula_cell_list;
+		
+		for (; cell_list; cell_list = cell_list->next){
+			Cell *cell = cell_list->data;
+
+			cell->generation = 0;
+		}
+		wb->generation = 1;
+	} else
+		wb->generation++;
+}
+
 void
 workbook_recalc (Workbook *wb)
 {
+	int generation;
 	Cell *cell;
-	GList *deps;
+	GList *deps, *l;
+
+	workbook_next_generation (wb);
+	generation = wb->generation;
 	
 	while ((cell = pick_next_cell_from_queue (wb))){
+		cell->generation = generation;
 		cell_eval (cell);
 		deps = cell_get_dependencies (cell->sheet, cell->col->pos, cell->row->pos);
-		if (deps)
-			cell_queue_recalc_list (deps);
+
+		for (l = deps ; l; l = l->next){
+			Cell *one_cell;
+
+			one_cell = l->data;
+			if (one_cell->generation != generation)
+				cell_queue_recalc (one_cell);
+		}
+		g_list_free (deps);
 	}
 }

src/expr.c

@@ -240,7 +240,7 @@ static Value *
 eval_cell_value (Sheet *sheet, Value *value)
 {
 	Value *res;
-	
+
 	res = g_new (Value, 1);
 	res->type = value->type;
 	
@@ -251,13 +251,11 @@ eval_cell_value (Sheet *sheet, Value *value)
 		break;
 		
 	case VALUE_INTEGER:
-		mpz_init (res->v.v_int);
-		mpz_set  (res->v.v_int, value->v.v_int);
+		res->v.v_int = value->v.v_int;
 		break;
 		
 	case VALUE_FLOAT:
-		mpf_init (res->v.v_float);
-		mpf_set (res->v.v_float, value->v.v_float);
+		res->v.v_float = value->v.v_float;
 		break;
 
 	case VALUE_ARRAY:
@@ -646,15 +644,20 @@ eval_expr (void *asheet, ExprTree *tree, int eval_col, int eval_row, char **erro
 		cell_get_abs_col_row (&tree->u.constant->v.cell, eval_col, eval_row, &col, &row);
 		
 		cell = sheet_cell_get (sheet, col, row);
-		
-		if (!cell || !cell->value){
-			res = g_new (Value, 1);
+
+		if (cell && cell->value){
+			if (cell->parsed_node && cell->generation != sheet->workbook->generation){
+				cell->generation = sheet->workbook->generation;
+				cell_eval (cell);
+			} 
 			
-			res->type = VALUE_INTEGER;
-			res->v.v_int = 0;
-		} else {
-			return eval_cell_value (sheet, cell->value);
+			if (cell->value)
+				return eval_cell_value (sheet, cell->value);
 		}
+		res = g_new (Value, 1);
+			
+		res->type = VALUE_INTEGER;
+		res->v.v_int = 0;
 		return res;
 	}
 	case OP_NEG:
@@ -668,6 +671,7 @@ eval_expr (void *asheet, ExprTree *tree, int eval_col, int eval_row, char **erro
 			return NULL;
 		}
 		res = g_new (Value, 1);
+		res->type = a->type;
 		if (a->type == VALUE_INTEGER){
 			res->v.v_int = -a->v.v_int;
 		} else {

src/sheet.h

@@ -33,6 +33,7 @@ typedef struct {
 	/* A queue with the cells to be evaluated */
 	GList      *eval_queue;
 	int        max_iterations;
+	guchar     generation;
 } Workbook;
 
 typedef struct {
@@ -168,6 +169,7 @@ void        workbook_attach_sheet        (Workbook *, Sheet *);
 Sheet      *workbook_focus_current_sheet (Workbook *wb);
 Sheet      *workbook_get_current_sheet   (Workbook *wb);
 void        workbook_auto_expr_label_set (Workbook *wb, char *text);
+void        workbook_next_generation     (Workbook *wb);
 
 /*
  * Does any pending recalculations