operations_research::Demon Class Reference

A Demon is the base element of a propagation queue. More...

#include <constraint_solver.h>

Inheritance diagram for operations_research::Demon:

List of all members.

Public Member Functions
	Demon ()
	This indicates the priority of a demon.
virtual	~Demon ()
virtual void	Run (Solver *const s)=0
	This is the main callback of the demon.
virtual Solver::DemonPriority	priority () const
	This method returns the priority of the demon.
virtual string	DebugString () const
void	inhibit (Solver *const s)
	This method inhibits the demon in the search tree below the current position.
void	desinhibit (Solver *const s)
	This method un-inhibit the demon that was inhibited.
Friends
class	Queue

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Detailed Description

A Demon is the base element of a propagation queue.

It is the main object responsible for implementing the actual propagation of the constraint and pruning the inconsistent values in the domains of the variables. The main concept is that demons are listeners that are attached to the variables and listen to their modifications. There are two methods:

• Run() is the actual methods that is called when the demon is processed
• priority() returns its priority. Standart priorities are slow, normal or fast. immediate is reserved for variables and are treated separately.

Definition at line 3153 of file constraint_solver.h.

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Constructor & Destructor Documentation

operations_research::Demon::Demon

(

)

[inline]

This indicates the priority of a demon.

Immediate demons are treated separately and corresponds to variables.

Definition at line 3157 of file constraint_solver.h.

virtual operations_research::Demon::~Demon

(

)

[inline, virtual]

Definition at line 3158 of file constraint_solver.h.

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Member Function Documentation

virtual void operations_research::Demon::Run

(

Solver *const

s

)

[pure virtual]

This is the main callback of the demon.

Implemented in operations_research::CallMethod0< T >, operations_research::CallMethod1< T, P >, operations_research::CallMethod2< T, P, Q >, operations_research::DelayedCallMethod0< T >, operations_research::DelayedCallMethod1< T, P >, and operations_research::DelayedCallMethod2< T, P, Q >.

Solver::DemonPriority operations_research::Demon::priority

(

)

const [virtual]

This method returns the priority of the demon.

Demon class.

Usually a demon is fast, slow or normal. Immediate demons are reserved for internal use to maintain variables.

Reimplemented in operations_research::DelayedCallMethod0< T >, operations_research::DelayedCallMethod1< T, P >, and operations_research::DelayedCallMethod2< T, P, Q >.

Definition at line 109 of file constraint_solver.cc.

string operations_research::Demon::DebugString

(

)

const [virtual]

Reimplemented from operations_research::BaseObject.

Reimplemented in operations_research::CallMethod0< T >, operations_research::CallMethod1< T, P >, operations_research::CallMethod2< T, P, Q >, operations_research::DelayedCallMethod0< T >, operations_research::DelayedCallMethod1< T, P >, and operations_research::DelayedCallMethod2< T, P, Q >.

Definition at line 113 of file constraint_solver.cc.

void operations_research::Demon::inhibit

(

Solver *const

s

)

This method inhibits the demon in the search tree below the current position.

Definition at line 117 of file constraint_solver.cc.

void operations_research::Demon::desinhibit

(

Solver *const

s

)

This method un-inhibit the demon that was inhibited.

Definition at line 123 of file constraint_solver.cc.

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Friends And Related Function Documentation

friend class Queue [friend]

Definition at line 3178 of file constraint_solver.h.

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The documentation for this class was generated from the following files:

• or-tools/src/constraint_solver/constraint_solver.h
• or-tools/src/constraint_solver/constraint_solver.cc