Erase

java.lang.Object
- org.projog.core.predicate.AbstractSingleResultPredicate
- - org.projog.core.predicate.builtin.db.Erase

All Implemented Interfaces:

KnowledgeBaseConsumer, PredicateFactory
```
public final class Erase
extends AbstractSingleResultPredicate
```
erase(X) - removes a record from the recorded database.
Removes from the recorded database the term associated with the reference specified by X. The goal succeeds even if there is no term associated with the specified reference.

Field Summary

Fields
Modifier and Type Field Description

private RecordedDatabase database

Constructor Summary

Constructors
Constructor Description

Erase()

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`protected boolean`	`evaluate(Term arg)`
`protected void`	`init()`	This method is called by `AbstractSingleResultPredicate.setKnowledgeBase(KnowledgeBase)`.

Methods inherited from class org.projog.core.predicate.AbstractSingleResultPredicate
evaluate, evaluate, evaluate, evaluate, evaluate, getArithmeticOperators, getFileHandles, getKnowledgeBase, getOperands, getPredicate, getPredicates, getProjogListeners, getSpyPoints, getTermFormatter, isRetryable, setKnowledgeBase

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.projog.core.predicate.PredicateFactory
isAlwaysCutOnBacktrack

- Field Detail
  - database
```
private RecordedDatabase database
```
- Constructor Detail
  - Erase
```
public Erase()
```
- Method Detail
  - init
```
protected void init()
```
    Description copied from class: AbstractSingleResultPredicate
    
    This method is called by AbstractSingleResultPredicate.setKnowledgeBase(KnowledgeBase).
    Can be overridden by subclasses to perform initialisation before any calls to AbstractSingleResultPredicate.evaluate(Term...) are made. As AbstractSingleResultPredicate.setKnowledgeBase(KnowledgeBase) will have already been called before this method is invoked, overridden versions will be able to access the KnowledgeBase using AbstractSingleResultPredicate.getKnowledgeBase().
    
    Overrides:
    
    init in class AbstractSingleResultPredicate
  - evaluate
```
protected boolean evaluate(Term arg)
```
    Overrides:
    
    evaluate in class AbstractSingleResultPredicate