/*
 * Copyright 2009 Yuichiro Moriguchi
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package net.morilib.lisp.nano;

/**
 * 
 *
 *
 * @author MORIGUCHI, Yuichiro 2009
 */
/*package*/ class Continuation extends Datum implements Callable {

	//
	private Object memento;

	//
	/*package*/ Continuation(Object memento) {
		if(memento == null) {
			throw new NullPointerException();
		}
		this.memento = memento;
	}

	/**
	 * @return the memento
	 */
	/*package*/ Object getMemento() {
		return memento;
	}

	/* (non-Javadoc)
	 * @see net.morilib.lisp.Datum#toDisplayString(java.lang.StringBuilder)
	 */
	@Override
	public String toDisplay() {
		return ("#<continuation " +
				Integer.toString(hashCode(), 16) + ">");
	}

}
