Initial Commit. Needs refactored to run tests in parallel. Needs to avoid copying objects into both unordered_maps and reference them instead.

DualLookup.h

@@ -0,0 +1,94 @@
+#ifndef DVEREB_DUALLOOKUP_H
+#define DVEREB_DUALLOOKUP_H
+
+#include <unordered_map>
+template <class T>
+class DualLookup {
+public:
+	DualLookup();
+
+	/* Add a mapped pair to the container
+	 *  returns false if it already exists, regardless of direction
+	 *   (i.e. value->equivilent is a duplicate of equivilent->value)
+	 */
+	bool add(T value, T equivilent);
+
+	/* If found, Set result to the mapped value and true is returned.
+	 * If not found, result remains unchanged and false is returned.
+	 */
+	bool get(T key, T &result);
+
+	/* If found, return true
+	 * else return false */
+	bool contains(const T &key);
+
+private:
+	std::unordered_map<T, T> owner;
+	std::unordered_map<T, T> mirror;
+
+	// NOTE(dev): These functions actually do the work:
+	bool get_single(T key, T &result, const std::unordered_map<T, T> &umap);
+	bool contains_single(const T &key, const std::unordered_map<T, T> &umap);
+};
+
+template <class T>
+DualLookup<T>::DualLookup()
+{
+}
+
+template <class T>
+bool DualLookup<T>::add(T value, T equivilent)
+{
+	// already exists
+	if(owner.find(value) != owner.end() || mirror.find(value) != mirror.end())
+		return false;
+	if(owner.find(equivilent) != owner.end() || mirror.find(equivilent) != mirror.end())
+		return false;
+
+	owner.insert({value, equivilent});
+	mirror.insert({equivilent, value});
+
+	return true;
+}
+
+template <class T>
+bool DualLookup<T>::get(T key, T &result)
+{
+	if(get_single(key, result, owner))
+		return true;
+	if(get_single(key, result, mirror))
+		return true;
+
+	return false; // didn't find it
+}
+
+template <class T>
+bool DualLookup<T>::contains(const T &key)
+{
+	if(contains_single(key, owner))
+		return true;
+	if(contains_single(key, mirror))
+		return true;
+
+	return false; // didn't find it
+}
+
+template <class T>
+bool DualLookup<T>::get_single(T key, T &result, const std::unordered_map<T, T> &umap)
+{
+	auto i = umap.find(key);
+	if(i == umap.end())
+		return false;
+
+	result = i->second;
+
+	return true;
+}
+
+template <class T>
+bool DualLookup<T>::contains_single(const T &key, const std::unordered_map<T, T> &umap)
+{
+	return umap.find(key) != umap.end();
+}
+
+#endif