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+/**
+ * <b>SOFTWARE RIGHTS</b>
+ * <p>
+ * ANTLR 2.6.0 MageLang Insitute, 1998
+ * <p>
+ * We reserve no legal rights to the ANTLR--it is fully in the
+ * public domain. An individual or company may do whatever
+ * they wish with source code distributed with ANTLR or the
+ * code generated by ANTLR, including the incorporation of
+ * ANTLR, or its output, into commerical software.
+ * <p>
+ * We encourage users to develop software with ANTLR. However,
+ * we do ask that credit is given to us for developing
+ * ANTLR. By "credit", we mean that if you use ANTLR or
+ * incorporate any source code into one of your programs
+ * (commercial product, research project, or otherwise) that
+ * you acknowledge this fact somewhere in the documentation,
+ * research report, etc... If you like ANTLR and have
+ * developed a nice tool with the output, please mention that
+ * you developed it using ANTLR. In addition, we ask that the
+ * headers remain intact in our source code. As long as these
+ * guidelines are kept, we expect to continue enhancing this
+ * system and expect to make other tools available as they are
+ * completed.
+ * <p>
+ * The ANTLR gang:
+ * @version ANTLR 2.6.0 MageLang Insitute, 1998
+ * @author Terence Parr, <a href=http://www.MageLang.com>MageLang Institute</a>
+ * @author <br>John Lilley, <a href=http://www.Empathy.com>Empathy Software</a>
+ * @author <br><a href="mailto:pete@yamuna.demon.co.uk">Pete Wells</a>
+ */
+
+#include "antlr/TokenBuffer.hpp"
+
+ANTLR_BEGIN_NAMESPACE(antlr)
+
+/**A Stream of Token objects fed to the parser from a TokenStream that can
+ * be rewound via mark()/rewind() methods.
+ * <p>
+ * A dynamic array is used to buffer up all the input tokens.  Normally,
+ * "k" tokens are stored in the buffer.  More tokens may be stored during
+ * guess mode (testing syntactic predicate), or when LT(i>k) is referenced.
+ * Consumption of tokens is deferred.  In other words, reading the next
+ * token is not done by conume(), but deferred until needed by LA or LT.
+ * <p>
+ *
+ * @see antlr.Token
+ * @see antlr.TokenStream
+ * @see antlr.TokenQueue
+ */
+
+/** Create a token buffer */
+TokenBuffer::TokenBuffer(TokenStream& input_)
+: input(input_)
+{ nMarkers=0; markerOffset=0; numToConsume=0; }
+
+/** Mark another token for deferred consumption */
+void TokenBuffer::consume()
+{ numToConsume++; }
+
+/** Ensure that the token buffer is sufficiently full */
+void TokenBuffer::fill(int amount)
+{
+	syncConsume();
+	// Fill the buffer sufficiently to hold needed tokens
+	while (queue.entries() < amount + markerOffset) {
+		// Append the next token
+		queue.append(input.nextToken());
+	}
+}
+
+/** Get a lookahead token value */
+int TokenBuffer::LA(int i)
+{
+	fill(i);
+	return queue.elementAt(markerOffset+i-1)->type;
+}
+
+/** Get a lookahead token */
+RefToken TokenBuffer::LT(int i)
+{
+	fill(i);
+	return queue.elementAt(markerOffset+i-1);
+}
+
+/**Return an integer marker that can be used to rewind the buffer to
+ * its current state.
+ */
+int TokenBuffer::mark()
+{
+	syncConsume();
+	nMarkers++;
+	return markerOffset;
+}
+
+/**Rewind the token buffer to a marker.
+ * @param mark Marker returned previously from mark()
+ */
+void TokenBuffer::rewind(int mark)
+{
+	syncConsume();
+	markerOffset=mark;
+	nMarkers--;
+}
+
+ANTLR_END_NAMESPACE
+