Class ClauseSubstitution

java.lang.Object

edu.harvard.seas.pl.abcdatalog.util.substitution.ClauseSubstitution

All Implemented Interfaces:

ConstOnlySubstitution, Substitution

public class ClauseSubstitution
extends Object
implements ConstOnlySubstitution

This is a substitution tailor-made for a particular clause. Mappings can only be added to the substitution in the order in which the variables appear in the clause. The state of the substitution can be reset (so that it "forgets" the most recent mappings).

Constructor Summary

Constructors

Constructor	Description
ClauseSubstitution(SemiNaiveClauseAnnotator.SemiNaiveClause c)

Method Summary

Modifier and Type	Method	Description
boolean	add(Variable x, Constant c)	Attempts to add a mapping to the substitution.
Term[]	apply(Term[] original)	Apply this substitution to a list of terms, creating a new list.
Constant	get(Variable x)	Retrieves the mapping of a variable.
ClauseSubstitution	getCleanCopy()
static void	main(String[] args)
void	resetState(int conj)
String	toString()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Details

ClauseSubstitution

public ClauseSubstitution(SemiNaiveClauseAnnotator.SemiNaiveClause c)

Method Details

getCleanCopy

public ClauseSubstitution getCleanCopy()

add

public boolean add(Variable x,
 Constant c)

Description copied from interface: ConstOnlySubstitution

Attempts to add a mapping to the substitution. Returns true if the mapping was made successfully (i.e., if the variable was not already mapped to another constant).

Specified by:

add in interface ConstOnlySubstitution

Parameters:

x - the variable

c - the constant

Returns:

whether the mapping was successfully added

get

public Constant get(Variable x)

Description copied from interface: ConstOnlySubstitution

Retrieves the mapping of a variable.

Specified by:

get in interface ConstOnlySubstitution

Specified by:

get in interface Substitution

Parameters:

x - the variable

Returns:

the constant that the variable is bound to, or null if the variable is not in the substitution

resetState

public void resetState(int conj)

toString

public String toString()

Overrides:

toString in class Object

main

public static void main(String[] args)
                 throws DatalogValidationException

Throws:

DatalogValidationException

apply

public Term[] apply(Term[] original)

Description copied from interface: Substitution

Apply this substitution to a list of terms, creating a new list.

Specified by:

apply in interface Substitution

Parameters:

original - the original list

Returns:

the new list