001/*
002 * Copyright 2010-2013 JetBrains s.r.o.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 * http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package org.jetbrains.jet.lang.parsing;
018
019import com.intellij.psi.tree.IElementType;
020
021public interface TokenStreamPattern {
022    /**
023     * Called on each token
024     *
025     * @param offset
026     * @param topLevel see {@link #isTopLevel(int, int, int, int)}
027     * @return <code>true</code> to stop
028     */
029    boolean processToken(int offset, boolean topLevel);
030
031    /**
032     * @return the position where the predicate has matched, -1 if no match was found
033     */
034    int result();
035
036    /**
037     * Decides if the combination of open bracet counts makes a "top level position"
038     * Straightforward meaning would be: if all counts are zero, then it's a top level
039     */
040    boolean isTopLevel(int openAngleBrackets, int openBrackets, int openBraces, int openParentheses);
041
042    /**
043     * Called on right parentheses, brackets, braces and angles (>)
044     * @param token the closing bracket
045     * @return true to stop matching, false to proceed
046     */
047    boolean handleUnmatchedClosing(IElementType token);
048}