dirty_cell_tracker

Defined in header: <ixion/dirty_cell_tracker.hpp>

class dirty_cell_tracker

This class is designed to track in-direct dependencies of dirty formula cells. A “dirty” formula cell is a formula cell whose result needs to be re-calculated because at one or more of its references have updated values.

This class also takes volatile functions into account when determining the status of the formula cell result. A volatile function is a cell function whose value needs to be re-calculated on every re-calculation. One example of a volatile function is NOW(), which returns the current time at the time of calculation.

Public Functions

dirty_cell_tracker(const dirty_cell_tracker&) = delete

dirty_cell_tracker &operator=(const dirty_cell_tracker&) = delete

dirty_cell_tracker()

~dirty_cell_tracker()

void add(const abs_range_t &src, const abs_range_t &dest)

Add a tracking relationship from a source cell or cell range to a destination cell or cell range.

Parameters:

• src – source cell or cell range that includes reference to (therefore listens to) the range.

• dest – destination cell or range referenced tracked by the source cell.

void remove(const abs_range_t &src, const abs_range_t &dest)

Remove an existing tracking relationship from a source cell or cell range to a destination cell or cell range. If no such relationship exists, it does nothing.

Parameters:

• src – cell or cell range that includes reference to the range.

• dest – cell or range referenced by the cell.

void add_volatile(const abs_range_t &pos)

Register a formula cell located at the specified position as volatile. Note that the caller should ensure that the cell at the specified position is indeed a formula cell.

Parameters:

pos – position of the cell to register as a volatile cell.

void remove_volatile(const abs_range_t &pos)

Remove the specified cell position from the internal set of registered volatile formula cells.

Parameters:

pos – position of the cell to unregister as a volatile cell.

abs_range_set_t query_dirty_cells(const abs_range_t &modified_cell) const

Get the positions of the formula cells that need re-calculating after a modification: the registered volatile cells, and the cells that directly or indirectly reference the modified cell.

Parameters:

modified_cell – Cell or range whose value has been modified.

Returns:

Positions of the dirty formula cells, in no particular order. A formula group appears as a single range.

abs_range_set_t query_dirty_cells(const abs_range_set_t &modified_cells) const

Get the positions of the formula cells that need re-calculating after modifications: the registered volatile cells, and the cells that directly or indirectly reference any of the modified cells.

Parameters:

modified_cells – Cells or ranges whose values have been modified.

Returns:

Positions of the dirty formula cells, in no particular order. A formula group appears as a single range.

std::vector<abs_range_t> query_and_sort_dirty_cells(const abs_range_t &modified_cell) const

Get the positions of the formula cells that need re-calculating after a modification, sorted in order of dependency so that each cell comes after the cells it depends on.

Parameters:

modified_cell – Cell or range whose value has been modified.

Returns:

Positions of the dirty formula cells in calculation order. A formula group appears as a single range.

std::vector<abs_range_t> query_and_sort_dirty_cells(const abs_range_set_t &modified_cells, const abs_range_set_t *dirty_formula_cells = nullptr) const

Get the positions of the formula cells that need re-calculating after modifications, sorted in order of dependency so that each cell comes after the cells it depends on.

Parameters:

• modified_cells – Cells or ranges whose values have been modified.

• dirty_formula_cells – Formula cells to treat as dirty regardless of the modifications, such as cells whose formulas are new or have changed. Their dependents get included as well.

Returns:

Positions of the dirty formula cells in calculation order. A formula group appears as a single range.

std::string to_string() const

Get a string representation of all tracked relationships, for debugging.

bool empty() const

Check whether the tracker has any tracked relationship. Registered volatile cells are not taken into account.