class BindMap {
public:

	// This class represents a mapping between a parameter name and its
	// associated parameter index in a prepared statement.
	class Pair {
		friend class BindMap;
		public:

			inline int GetIndex() {
				return index;
			}

			inline v8::Local<v8::String> GetName(v8::Isolate* isolate) {
				return v8::Local<v8::String>::New(isolate, name);
			}

		private:
			explicit Pair(v8::Isolate* isolate, const char* _name, int _index)
				: name(isolate, InternalizedFromUtf8(isolate, _name, -1)), index(_index) {}

			explicit Pair(v8::Isolate* isolate, Pair* pair)
				: name(isolate, pair->name), index(pair->index) {}

			const CopyablePersistent<v8::String> name;
			const int index;
	};

	explicit BindMap(char _) {
		assert(_ == 0);
		pairs = NULL;
		capacity = 0;
		length = 0;
	}

	~BindMap() {
		while (length) pairs[--length].~Pair();
		FREE_ARRAY<Pair>(pairs);
	}

	inline Pair* GetPairs() { return pairs; }
	inline int GetSize() { return length; }

	// Adds a pair to the bind map, expanding the capacity if necessary.
	void Add(v8::Isolate* isolate, const char* name, int index) {
		assert(name != NULL);
		if (capacity == length) Grow(isolate);
		new (pairs + length++) Pair(isolate, name, index);
	}

private:
	void Grow(v8::Isolate* isolate) {
		assert(capacity == length);
		capacity = (capacity << 1) | 2;
		Pair* new_pairs = ALLOC_ARRAY<Pair>(capacity);
		for (int i=0; i<length; ++i) {
			new (new_pairs + i) Pair(isolate, pairs + i);
			pairs[i].~Pair();
		}
		FREE_ARRAY<Pair>(pairs);
		pairs = new_pairs;
	}

	Pair* pairs;
	int capacity;
	int length;
};