Eiffeldoc: BACKTRACKING

current_continuation = Void or current_continuation = top_sequence
top_sequence = Void implies current_continuation = Void

Overview

Features

{ANY}

set_current_node (node: BACKTRACKING_NODE)

Sets the next node of the BACKTRACKING_NODE graph to evaluate.
push_and (node: BACKTRACKING_NODE)

Pushes node in front of the continuation path.
push_and_list (list: BACKTRACKING_NODE_AND_LIST)

Pushes list in front of the continuation path.
push_or (node: BACKTRACKING_NODE)

Pushes node in front of the possible alternatives.
push_or_list (list: BACKTRACKING_NODE_OR_LIST)

Pushes list in front of the possible alternatives.

internal

{}

current_node: BACKTRACKING_NODE

Current node of the BACKTRACKING_NODE graph to be evaluated.
evaluate_current_state

That feature is called to evaluate the current state

Common client features

{ANY}

search_first

Resets all and searches the first solution.
search_next

Searches the next solution.
search_is_success: BOOLEAN

True when search is successful
is_off: BOOLEAN

True when search is finished
clear

Clears the current state to nothing.
is_cleared: BOOLEAN

True if no partial data remain in the current state

Control of the exploration

{ANY}

push_sequence (sequence: ABSTRACT_BACKTRACKING_SEQUENCE)

Pushes the sequence in front of the continuation path.
push_alternative (alternative: ABSTRACT_BACKTRACKING_ALTERNATIVE)

Pushes the alternative before the continuation path.
continue

Continues the exploration of the current path.
backtrack

Stops the exploration of the current path and tries to explore the next alternative path.
push_cut_point

Inserts a cut point into the continuation path.
cut

Removes the alternatives until the one recorded by the next cut point in the continuation path.
cut_all

Cuts all alternatives.

Internal

{}

stop_search_loop: BOOLEAN

True if at the end of a search.
search

Common search loop to search_first and search_next
cut_until (alternative: ABSTRACT_BACKTRACKING_ALTERNATIVE)

Cut all alternatives until 'alternative'.

Internal deferred

{}

context_clear

Clear any saved context.
context_push

Push the current context.
context_restore

Restore the context to the last saved one.
context_restore_and_pop

Restore the context to the last saved one and drop it.
context_cut

Remove the last saved context.

Specific to sequences

top_sequence: ABSTRACT_BACKTRACKING_SEQUENCE

Stack of sequences represented by its top (can be Void)
current_continuation: ABSTRACT_BACKTRACKING_SEQUENCE

The current continuation path
pop_sequence

Removes the current sequence and replace it by the next sequence in the continuation path.

Specific to alternatives

top_alternative: ABSTRACT_BACKTRACKING_ALTERNATIVE

Stack of alternatives represented by its top (can be Void)
continue_alternative

Returns to the alternative on the top of the stack and put its saved continuation path as the current continuation path.
pop_alternative

Returns to the alternative on the top of the stack and put its saved continuation path as the current continuation path.

internal: allocation and collection

{}

remove_top_sequence

Removes the top sequence.
remove_top_alternative

Removes the top alternative.

{ANY}

pool_of_cut_points: ABSTRACT_BACKTRACKING_POOL_OF_CUT_POINT

Bank of cut points

the pools

{ANY}

set_current_node (node: BACKTRACKING_NODE)

effective procedure

{ANY}

Sets the next node of the BACKTRACKING_NODE graph to evaluate.

push_and (node: BACKTRACKING_NODE)

effective procedure

{ANY}

Pushes node in front of the continuation path.

push_and_list (list: BACKTRACKING_NODE_AND_LIST)

effective procedure

{ANY}

Pushes list in front of the continuation path.

push_or (node: BACKTRACKING_NODE)

effective procedure

{ANY}

Pushes node in front of the possible alternatives.

push_or_list (list: BACKTRACKING_NODE_OR_LIST)

effective procedure

{ANY}

Pushes list in front of the possible alternatives.

current_node: BACKTRACKING_NODE

writable attribute

{}

Current node of the BACKTRACKING_NODE graph to be evaluated.

evaluate_current_state

effective procedure

{}

That feature is called to evaluate the current state

search_first

effective procedure

{ANY}

Resets all and searches the first solution.

search_next

effective procedure

{ANY}

Searches the next solution.

search_is_success: BOOLEAN

writable attribute

{ANY}

True when search is successful

is_off: BOOLEAN

effective function

{ANY}

True when search is finished

clear

effective procedure

{ANY}

Clears the current state to nothing.

is_cleared: BOOLEAN

effective function

{ANY}

True if no partial data remain in the current state

push_sequence (sequence: ABSTRACT_BACKTRACKING_SEQUENCE)

effective procedure

{ANY}

Pushes the sequence in front of the continuation path.

push_alternative (alternative: ABSTRACT_BACKTRACKING_ALTERNATIVE)

effective procedure

{ANY}

Pushes the alternative before the continuation path.

continue

effective procedure

{ANY}

Continues the exploration of the current path.

backtrack

effective procedure

{ANY}

Stops the exploration of the current path and tries to explore the next alternative path.

push_cut_point

effective procedure

{ANY}

Inserts a cut point into the continuation path.

cut

effective procedure

{ANY}

Removes the alternatives until the one recorded by the next cut point in the continuation path.

cut_all

effective procedure

{ANY}

Cuts all alternatives.

stop_search_loop: BOOLEAN

writable attribute

{}

True if at the end of a search.

effective procedure

{}

Common search loop to search_first and search_next

cut_until (alternative: ABSTRACT_BACKTRACKING_ALTERNATIVE)

effective procedure

{}

Cut all alternatives until 'alternative'.

context_clear

deferred procedure

{}

Clear any saved context.

context_push

deferred procedure

{}

Push the current context.

context_restore

deferred procedure

{}

Restore the context to the last saved one.

context_restore_and_pop

deferred procedure

{}

Restore the context to the last saved one and drop it.

context_cut

deferred procedure

{}

Remove the last saved context.

top_sequence: ABSTRACT_BACKTRACKING_SEQUENCE

writable attribute

Stack of sequences represented by its top (can be Void)

current_continuation: ABSTRACT_BACKTRACKING_SEQUENCE

writable attribute

The current continuation path

pop_sequence

effective procedure

Removes the current sequence and replace it by the next sequence in the continuation path.

top_alternative: ABSTRACT_BACKTRACKING_ALTERNATIVE

writable attribute

Stack of alternatives represented by its top (can be Void)

continue_alternative

effective procedure

Returns to the alternative on the top of the stack and put its saved continuation path as the current continuation path.

pop_alternative

effective procedure

Returns to the alternative on the top of the stack and put its saved continuation path as the current continuation path.

remove_top_sequence

effective procedure

{}

Removes the top sequence.

remove_top_alternative

effective procedure

{}

Removes the top alternative.

pool_of_cut_points: ABSTRACT_BACKTRACKING_POOL_OF_CUT_POINT

once function

{ANY}

Bank of cut points

pool_of_sequence: BACKTRACKING_POOL_OF_SEQUENCE

once function

{ANY}

pool_of_sequence_list: BACKTRACKING_POOL_OF_SEQUENCE_LIST

once function

{ANY}

pool_of_alternative: BACKTRACKING_POOL_OF_ALTERNATIVE

once function

{ANY}

pool_of_alternative_list: BACKTRACKING_POOL_OF_ALTERNATIVE_LIST

once function

{ANY}