antlr-runtime/antlr-3.4/runtime/ActionScript/project/src/org/antlr/runtime/TokenStream.as

/*
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 Copyright (c) 2005-2006 Terence Parr
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package org.antlr.runtime {

	/** A stream of tokens accessing tokens from a TokenSource */
	public interface TokenStream extends IntStream {
	    /** Get Token at current input pointer + i ahead where i=1 is next Token.
		 *  i<0 indicates tokens in the past.  So -1 is previous token and -2 is
		 *  two tokens ago. LT(0) is undefined.  For i>=n, return Token.EOFToken.
		 *  Return null for LT(0) and any index that results in an absolute address
		 *  that is negative.
		 */
	    function LT(k:int):Token;
	
		/** Get a token at an absolute index i; 0..n-1.  This is really only
		 *  needed for profiling and debugging and token stream rewriting.
		 *  If you don't want to buffer up tokens, then this method makes no
		 *  sense for you.  Naturally you can't use the rewrite stream feature.
		 *  I believe DebugTokenStream can easily be altered to not use
		 *  this method, removing the dependency.
		 */
		function getToken(i:int):Token;
	
		/** Where is this stream pulling tokens from?  This is not the name, but
		 *  the object that provides Token objects.
		 */
		function get tokenSource():TokenSource;
	
		/** Return the text of all tokens from start to stop, inclusive.
		 *  If the stream does not buffer all the tokens then it can just
		 *  return "" or null;  Users should not access $ruleLabel.text in
		 *  an action of course in that case.
		 */
		function toStringWithRange(start:int, stop:int):String;
	
		/** Because the user is not required to use a token with an index stored
		 *  in it, we must provide a means for two token objects themselves to
		 *  indicate the start/end location.  Most often this will just delegate
		 *  to the other toString(int,int).  This is also parallel with
		 *  the TreeNodeStream.toString(Object,Object).
		 */
		function toStringWithTokenRange(start:Token, stop:Token):String;
	}

}