/*
* Copyright (c) 2007 BUSINESS OBJECTS SOFTWARE LIMITED
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* * Neither the name of Business Objects nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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*/
/*
* NEqualsRecord.java
* Created: Jul 28, 2005
* By: Raymond Cypher
*/
package org.openquark.cal.internal.machine.g.functions;
import java.util.List;
import org.openquark.cal.compiler.QualifiedName;
import org.openquark.cal.internal.machine.g.Executor;
import org.openquark.cal.internal.machine.g.NPrimitiveFunc;
import org.openquark.cal.internal.machine.g.NRecordValue;
import org.openquark.cal.internal.machine.g.NValBoolean;
import org.openquark.cal.internal.machine.g.NValInt;
import org.openquark.cal.internal.machine.g.Node;
import org.openquark.cal.internal.module.Cal.Core.CAL_Prelude_internal;
import org.openquark.cal.module.Cal.Core.CAL_Prelude;
import org.openquark.cal.runtime.CALExecutorException;
/**
* Implementation of Prelude.equalsRecord
*/
public class NEqualsRecord extends NPrimitiveFunc {
public static final QualifiedName name = CAL_Prelude_internal.Functions.equalsRecord;
public static final NEqualsRecord instance = new NEqualsRecord ();
private static final NValBoolean boolean_false = new NValBoolean (false);
private static final NValBoolean boolean_true = new NValBoolean (true);
private NValInt indexOfEqualsClassMethod = null;
private NEqualsRecord () {/* Constructor made private to control creation. */ }
@Override
protected int getArity () {
return 3;
}
@Override
protected QualifiedName getName () {
return name;
}
/**
* Compute the equality of two records and return the resulting boolean.
*/
@Override
public Node doEvaluation (Node[] arguments, Executor executor)
throws CALExecutorException {
//equalsRecord recordDictionary x y.
//the compiler ensures that the 3 record arguments all have the same fields.
//we iterate in FieldName order over the field names so that the function is well-defined in the presence of side effects.
//If f is a field, then recordDictionary.f is the dictionary for use when calling the class method Prelude.equals on
//the values x.f and y.f.
// Evaluate the three arguments.
NRecordValue recordDictionary = (NRecordValue) executor.internalEvaluate(arguments[0]);
NRecordValue x = (NRecordValue) executor.internalEvaluate(arguments[1]);
NRecordValue y = (NRecordValue) executor.internalEvaluate(arguments[2]);
NValInt classMethodIndex = getIndexOfEqualsClassMethod(executor);
List<String> fieldNames = recordDictionary.fieldNames();
final int nFields = fieldNames.size();
for (int i = 0; i < nFields; ++i) {
String fieldName = fieldNames.get(i);
Node valueDictionaryThunk = recordDictionary.getValue(fieldName);
Node xValueThunk = x.getValue(fieldName);
Node yValueThunk = y.getValue(fieldName);
//compute "Prelude.equals valueDictionaryThunk xValueThunk yValueThunk"
//this is just (after inlining Prelude.equals d = d classMethodIndex"
if (!((NValBoolean)executor.internalEvaluate(valueDictionaryThunk.apply(classMethodIndex).apply(xValueThunk).apply(yValueThunk))).getBooleanValue()) {
return boolean_false;
}
}
return boolean_true;
}
/**
* Retrieve the current index of the equals class method.
* @param executor
* @return - NValInt holding the index.
*/
private final NValInt getIndexOfEqualsClassMethod (Executor executor) {
if (indexOfEqualsClassMethod == null) {
final int index = classMethodDictionaryIndex(executor, CAL_Prelude.Functions.equals);
indexOfEqualsClassMethod = new NValInt(index);
}
return indexOfEqualsClassMethod;
}
}