1.6 The class OZ_FSetVar

An instance of this class is a mapping of a finite set constraint variable on the heap of the emulator to a C/C++ data structure. The provided functionality allows to directly manipulate the domain (constraint) of the heap variable.

1.6.1 Constructor Member Functions

OZ_FSetVar

OZ_FSetVar(void);

This constructor creates an uninitialised instance of the class OZ_FSetVar, which can be initialised later by the member functions ask(), read(), or readEncap().

OZ_FSetVar

OZ_FSetVar(OZ_Term v);

This constructor creates an instance of the class OZ_FSetVar and initialises it using read().

1.6.2 Operator Member Functions

new

static void * operator new(size_t);

This operator allocates memory for a single instance of class OZ_FSetVar. This operator must only be used inside the member function propagate() of the class OZ_Propagator. The allocated memory is automatically reclaimed when propagate() is left.

new[]

static void * operator new[](size_t);

This operator allocates memory for an array of instances of OZ_FSetVar. This operator must only be used inside the member function propagate() of the class OZ_Propagator. The allocated memory is automatically reclaimed when propagate() is left.

delete

static void operator delete(void *, size_t);

This operator is a dummy since reclaiming memory happens automatically.

delete[]

static void operator delete[](void *, size_t);

This operator is a dummy since reclaiming memory happens automatically.

operator *

OZ_FSetConstraint &operator * (void);

This operator returns a finite set constraint representing the constraint of this variable.

operator ->

OZ_FSetConstraint * operator -> (void);

This operator returns a pointer to a finite set constraint representing the constraint of this variable.

1.6.3 Member Functions

isTouched

OZ_Boolean isTouched(voidconst;

This function returns OZ_TRUE if at least one element has been removed from or added to the set and otherwise OZ_FALSE.

ask

void ask(OZ_Term);

This member function initialises an instance of OZ_FSetVar for only reading constraints from the store and it does not require a call of leave() or fail().

read

void read(OZ_Term);

This member function initialises an instance of OZ_FSetVar for constraints to be read from and to be written to the constraint store. Using this function requires to call either leave() or fail() when leaving the member function propagate() of class OZ_Propagator.

readEncap

void readEncap(OZ_Term);

This member function initialises an instance of OZ_FSetVar for constraints to be read from the constraint store and to perform encapsulated constraint propagation as required by reified constraint propagators. Using this function requires to call either leave() or fail() when leaving the member function OZ_Propagator::propagate(). For further details see Section 1.7.3 of ``The Mozart Constraint Extensions Tutorial''.

leave

OZ_Boolean leave(void);

This member function has to be applied to each object of type OZ_FSetVar when leaving the function propagate() of class OZ_Propagator and no inconsistency was detected (except it was initialised with ask()). If the set constraint denotes a set value this member function returns OZ_FALSE and else it returns OZ_TRUE.

fail

void fail(void);

This member function has to be applied to each object of type OZ_FSetVar when leaving the function propagate() of class OZ_Propagator and inconsistency was detected (except it was initialised with ask()).

dropParameter

void dropParameter(void);

This member function removes the parameter associated with *this from the parameter set of the current propagator. This function takes care of multiple occurrences of a single variable as parameter, i.e., a parameter is removed if there is only one occurrence of the corresponding variable in the set of parameter left.


Tobias Müller
Version 1.4.0 (20080702)