add antlr

lib/antlr4/include/support/BitSet.h

@@ -0,0 +1,76 @@
+/* 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 antlrcpp {
+
+  class ANTLR4CPP_PUBLIC BitSet : public std::bitset<2048> {
+  public:
+    size_t nextSetBit(size_t pos) const {
+      for (size_t i = pos; i < size(); i++){
+        if (test(i)) {
+          return i;
+        }
+      }
+
+      return INVALID_INDEX;
+    }
+
+    // Prints a list of every index for which the bitset contains a bit in true.
+    friend std::wostream& operator << (std::wostream& os, const BitSet& obj)
+    {
+      os << "{";
+      size_t total = obj.count();
+      for (size_t i = 0; i < obj.size(); i++){
+        if (obj.test(i)){
+          os << i;
+          --total;
+          if (total > 1){
+            os << ", ";
+          }
+        }
+      }
+
+      os << "}";
+      return os;
+    }
+
+    static std::string subStringRepresentation(const std::vector<BitSet>::iterator &begin,
+                                                const std::vector<BitSet>::iterator &end) {
+      std::string result;
+      std::vector<BitSet>::iterator vectorIterator;
+
+      for (vectorIterator = begin; vectorIterator != end; vectorIterator++) {
+        result += vectorIterator->toString();
+      }
+      // Grab the end
+      result += end->toString();
+
+      return result;
+    }
+
+    std::string toString(){
+      std::stringstream stream;
+      stream << "{";
+      bool valueAdded = false;
+      for (size_t i = 0; i < size(); ++i){
+        if (test(i)){
+          if (valueAdded) {
+            stream << ", ";
+          }
+          stream << i;
+          valueAdded = true;
+        }
+      }
+
+      stream << "}";
+      return stream.str();
+    }
+
+  };
+}