YieldTree.java

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
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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();
}