CalFunction.java

/*
 * 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
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 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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 * POSSIBILITY OF SUCH DAMAGE.
 */


/*
 * CalFunction.java
 * Created: Nov 3, 2006
 * By: Bo Ilic
 */

package org.openquark.cal.runtime;

/**
 * A Java object of this type is produced by the CAL function:
 * Prelude.makeCalFunction :: (JObject -> JObject) -> CalFunction;
 * <p>
 * CalFunction allows a Java client to initiate the evaluation of 'makeCalFunction f' for a particular argument
 * value supplied by the Java client.
 * 
 * @author Bo Ilic
 */
public interface CalFunction {
    
    /**
     * If this CalFunction object was produced by calling 'makeCalFunction f', then calling evaluate(argument) results in
     * CAL evaluating the expression 'f argument' and then returning the result.
     * @param argument the argument to supply to f
     * @return the result of evaluating 'f argument'
     */
    public Object evaluate (Object argument);      
}