add antlr

lib/antlr4/include/misc/Predicate.h

@@ -0,0 +1,21 @@
+/* Copyright (c) 2012-2017 The ANTLR Project. All rights reserved.
+ * Use of this file is governed by the BSD 3-clause license that
+ * can be found in the LICENSE.txt file in the project root.
+ */
+
+#pragma once
+
+#include "antlr4-common.h"
+
+namespace antlr4 {
+namespace misc {
+
+  class ANTLR4CPP_PUBLIC Predicate {
+  public:
+    virtual ~Predicate();
+
+    virtual bool test(tree::ParseTree *t) = 0;
+  };
+
+} // namespace tree
+} // namespace antlr4