1 /* 2 * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 package jdk.nashorn.api.tree; 27 28 /** 29 * 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. 30 * 31 * For example: 32 * <pre> 33 * <em>function*</em> id(){ 34 * var index = 0; 35 * while(index < 10) 36 * <em>yield index++;</em> 37 * } 38 * </pre> 39 * 40 * @since 9 41 */ 42 public interface YieldTree extends ExpressionTree { 43 /** 44 * Returns the expression that is yielded. 45 * 46 * @return The expression that is yielded. 47 */ 48 ExpressionTree getExpression(); 49 50 /** 51 * Is this a yield * expression in a generator function? 52 * 53 * For example: 54 * <pre> 55 * function* id(){ 56 * yield 1; 57 * <em>yield * anotherGeneratorFunc();</em> 58 * yield 10; 59 * } 60 * </pre> 61 * 62 * 63 * @return true if this is a yield * expression 64 */ 65 boolean isStar(); 66 }