1/* 2 [The "BSD licence"] 3 Copyright (c) 2005-2006 Terence Parr 4 All rights reserved. 5 6 Redistribution and use in source and binary forms, with or without 7 modification, are permitted provided that the following conditions 8 are met: 9 1. Redistributions of source code must retain the above copyright 10 notice, this list of conditions and the following disclaimer. 11 2. Redistributions in binary form must reproduce the above copyright 12 notice, this list of conditions and the following disclaimer in the 13 documentation and/or other materials provided with the distribution. 14 3. The name of the author may not be used to endorse or promote products 15 derived from this software without specific prior written permission. 16 17 THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 18 IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 19 OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 20 IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 21 INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 22 NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26 THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27*/ 28package org.antlr.runtime { 29 /** A source of characters for an ANTLR lexer */ 30 public interface CharStream extends IntStream { 31 32 /** For infinite streams, you don't need this; primarily I'm providing 33 * a useful interface for action code. Just make sure actions don't 34 * use this on streams that don't support it. 35 */ 36 function substring(start:int, stop:int):String; 37 38 /** Get the ith character of lookahead. This is the same usually as 39 * LA(i). This will be used for labels in the generated 40 * lexer code. I'd prefer to return a char here type-wise, but it's 41 * probably better to be 32-bit clean and be consistent with LA. 42 */ 43 function LT(i:int):int; 44 45 /** ANTLR tracks the line information automatically */ 46 function get line():int; 47 48 /** Because this stream can rewind, we need to be able to reset the line */ 49 function set line(line:int):void; 50 51 function set charPositionInLine(pos:int):void; 52 53 /** The index of the character relative to the beginning of the line 0..n-1 */ 54 function get charPositionInLine():int; 55 } 56 57}