1 files changed, 34 insertions, 0 deletions
diff --git a/poxml/antlr/src/TokenStreamBasicFilter.cpp b/poxml/antlr/src/TokenStreamBasicFilter.cpp
new file mode 100644
index 00000000..71257f46
--- /dev/null
+++ b/poxml/antlr/src/TokenStreamBasicFilter.cpp
@@ -0,0 +1,34 @@
+#include "antlr/TokenStreamBasicFilter.hpp"
+
+ANTLR_BEGIN_NAMESPACE(antlr)
+
+/** This object is a TokenStream that passes through all
+ *  tokens except for those that you tell it to discard.
+ *  There is no buffering of the tokens.
+ */
+TokenStreamBasicFilter::TokenStreamBasicFilter(TokenStream& input_)
+: input(&input_)
+{
+}
+
+void TokenStreamBasicFilter::discard(int ttype)
+{
+	discardMask.add(ttype);
+}
+
+void TokenStreamBasicFilter::discard(const BitSet& mask)
+{
+	discardMask = mask;
+}
+
+RefToken TokenStreamBasicFilter::nextToken()
+{
+	RefToken tok = input->nextToken();
+	while ( tok && discardMask.member(tok->getType()) ) {
+		tok = input->nextToken();
+	}
+	return tok;
+}
+
+ANTLR_END_NAMESPACE
+