| /******************************************************************************* |
| * Copyright (c) 2006, 2009 IBM Corporation and others. |
| * |
| * This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License 2.0 |
| * which accompanies this distribution, and is available at |
| * https://www.eclipse.org/legal/epl-2.0/ |
| * |
| * SPDX-License-Identifier: EPL-2.0 |
| * |
| * Contributors: |
| * IBM Corporation - initial API and implementation |
| *******************************************************************************/ |
| package org.eclipse.cdt.core.dom.lrparser.action; |
| |
| import java.util.List; |
| |
| import lpg.lpgjavaruntime.IToken; |
| |
| /** |
| * Provides an interface to the token stream that |
| * can be used by the parser semantic actions. |
| * |
| * Allows the semantic actions to directly inspect the token |
| * stream. Used to calculate AST node offsets and for |
| * other purposes. |
| * |
| * TODO There are still issues with getLeftIToken() and |
| * getRightIToken(), they should return null when used with |
| * an empty rule but currently they don't. |
| * |
| * @author Mike Kucera |
| */ |
| public interface ITokenStream { |
| |
| /** |
| * Returns the tokens that were parsed to recognized |
| * the currently executing rule. |
| * |
| * @returns a read-only list of tokens, will not be null but may be empty |
| */ |
| public List<IToken> getRuleTokens(); |
| |
| /** |
| * Usually equivalent to getRuleTokens().get(0); but more efficient. |
| * |
| * However, when called during an empty rule it will return the token to the |
| * left of the location of the empty rule. |
| */ |
| public IToken getLeftIToken(); |
| |
| /** |
| * Usually equivalent to getRuleTokens().get(getRuleTokens().size()-1); but more efficient. |
| * |
| * However, when called during an empty rule it will return the token to the |
| * right of the location of the empty rule. |
| */ |
| public IToken getRightIToken(); |
| |
| /** |
| * Returns the orderedTerminalSymbol field of the corresponding sym class |
| * generated by LPG. |
| */ |
| public String[] getOrderedTerminalSymbols(); |
| |
| /** |
| * Returns the parser's name, useful for debugging. |
| */ |
| public String getName(); |
| } |