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 * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

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 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

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 *

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package jdk.nashorn.api.tree;

/**

 *  A tree node for <a href="http://www.ecma-international.org/ecma-262/6.0/#sec-generator-function-definitions">yield expressions</a> used in generator functions.

 *

 * For example:

 * <pre>

 * <em>function*</em> id(){

 *     var index = 0;

 *     while(index < 10)

 *         <em>yield index++;</em>

 * }

 * </pre>

 *

 * @since 9

 */

public interface YieldTree extends ExpressionTree {

    /**

     * Returns the expression that is yielded.

     *

     * @return The expression that is yielded.

     */

    ExpressionTree getExpression();

    /**

     * Is this a yield * expression in a generator function?

     *

     * For example:

     * <pre>

     * function* id(){

     *     yield 1;

     *     <em>yield * anotherGeneratorFunc();</em>

     *     yield 10;

     * }

     * </pre>

     *

     *

     * @return true if this is a yield * expression

     */

    boolean isStar();

}