org.deri.iris.builtins
Class ExactEqualBuiltin

java.lang.Object
  org.deri.iris.builtins.AbstractBuiltin
      org.deri.iris.builtins.ArithmeticBuiltin
          org.deri.iris.builtins.ExactEqualBuiltin

All Implemented Interfaces:

Comparable<IAtom>, IAtom, IBuiltinAtom

public class ExactEqualBuiltin
extends ArithmeticBuiltin

Built-in to either: a) compare two terms for exact equality, OR b) assign a constant expression to a variable Two terms are exactly equal if they: a) have exactly the same type, AND b) have the same value This comparison respects floating point round-off errors.

Field Summary

Fields inherited from class org.deri.iris.builtins.AbstractBuiltin

EMPTY_TERM

Constructor Summary

ExactEqualBuiltin(ITerm... t)
Constructor.

Method Summary

protected ITerm	computeMissingTerm(int missingTermIndex, ITerm[] terms) Compute the missing term when the other two are known.
protected boolean	testForEquality(ITerm t0, ITerm t1)

Methods inherited from class org.deri.iris.builtins.ArithmeticBuiltin

evaluateTerms, maxUnknownVariables

Methods inherited from class org.deri.iris.builtins.AbstractBuiltin

compareTo, equals, evaluate, getPredicate, getTuple, hashCode, isBuiltin, isGround, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

ExactEqualBuiltin

public ExactEqualBuiltin(ITerm... t)

Constructor.

Parameters:

terms - The terms, must be two of these

Method Detail

computeMissingTerm

protected ITerm computeMissingTerm(int missingTermIndex,
                                   ITerm[] terms)

Description copied from class: ArithmeticBuiltin

Compute the missing term when the other two are known.

Specified by:

computeMissingTerm in class ArithmeticBuiltin

terms - The collection of all terms.

Returns:

The computed value.

testForEquality

protected boolean testForEquality(ITerm t0,
                                  ITerm t1)

Overrides:

testForEquality in class ArithmeticBuiltin