Class GetCode

java.lang.Object

org.projog.core.predicate.AbstractSingleResultPredicate

org.projog.core.predicate.builtin.io.GetCode

All Implemented Interfaces:

KnowledgeBaseConsumer, PredicateFactory

public final class GetCode
extends AbstractSingleResultPredicate

get_code(X) - reads the next character from the input stream.

The goal succeeds if X can be unified with next character read from the current input stream. Succeeds only once and the operation of moving to the next character is not undone on backtracking.

If there are no more characters to read from the current input stream (i.e. if the end of the stream has been reached) then an attempt is made to unify X with the value -1.

Constructor Summary

Constructors

Constructor	Description
GetCode()

Method Summary

Modifier and Type	Method	Description
protected boolean	evaluate(Term argument)

Methods inherited from class AbstractSingleResultPredicate

evaluate, evaluate, evaluate, evaluate, getArithmeticOperators, getFileHandles, getKnowledgeBase, getOperands, getPredicate, getPredicates, getProjogListeners, getSpyPoints, getTermFormatter, init, isRetryable, setKnowledgeBase

Methods inherited from class Object

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

Methods inherited from interface PredicateFactory

isAlwaysCutOnBacktrack, preprocess

Constructor Details

GetCode

public GetCode()

Method Details

evaluate

protected boolean evaluate(Term argument)

Overrides:

evaluate in class AbstractSingleResultPredicate