Package org.tweetyproject.lp.asp.syntax

Class ASPBodyElement

java.lang.Object

org.tweetyproject.lp.asp.syntax.ASPElement

org.tweetyproject.lp.asp.syntax.ASPBodyElement

All Implemented Interfaces:

Formula, ComplexLogicalFormula, LogicStructure, SimpleLogicalFormula

Direct Known Subclasses:

AggregateAtom, ASPLiteral, ComparativeAtom, DefaultNegation, OptimizationStatement

public abstract class ASPBodyElement
extends ASPElement

This class is a common base class for ASP formulas that can be part of an ASP rule body (premise of a rule):

• Literals (i.e. atoms or strictly negated atoms)
• Built-in atoms (i.e. terms connected by comparative operators like == and !=)
• Aggregate atoms
• Default negations of literals or aggregates (i.e. 'not a' a for a literal or aggregate a)

Note: In the ASP-Core-2 standard, the formulas represented by this class are also referred to as 'Literals'. In the TweetyProject ASP library, literals are only atoms or the strict negations of atoms.

Author:

Tim Janus, Anna Gessler

Constructor Summary

Constructors

Constructor	Description
ASPBodyElement()	Default Constructor

Method Summary

Modifier and Type	Method	Description
abstract SortedSet<ASPLiteral>	getLiterals()	Returns all literals in this element in form of a SortedSet.
abstract ASPBodyElement	substitute(Term<?> t, Term<?> v)	Substitutes all occurrences of term "v" in this formula by term "t" and returns the new formula.

Methods inherited from class org.tweetyproject.lp.asp.syntax.ASPElement

clone, containsTermsOfType, exchange, getAtoms, getPredicateCls, getPredicates, getSignature, isGround, isWellFormed, printToClingo, printToDLV, substitute

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.tweetyproject.logics.commons.syntax.interfaces.LogicStructure

getTerms, getTerms

Methods inherited from interface org.tweetyproject.logics.commons.syntax.interfaces.SimpleLogicalFormula

equals, hashCode, isLiteral

Constructor Details

ASPBodyElement

public ASPBodyElement()

Default Constructor

Method Details

getLiterals

public abstract SortedSet<ASPLiteral> getLiterals()

Returns all literals in this element in form of a SortedSet. Literals are atoms or strict negations of atoms.

Returns:

all the literals used in the rule element

substitute

public abstract ASPBodyElement substitute(Term<?> t,
 Term<?> v)

Description copied from interface: ComplexLogicalFormula

Substitutes all occurrences of term "v" in this formula by term "t" and returns the new formula.

Specified by:

substitute in interface ComplexLogicalFormula

Specified by:

substitute in class ASPElement

Parameters:

t - the term to be substituted.

v - the term to substitute.

Returns:

a formula where every occurrence of "v" is replaced by "t".