- update "common" subfolder.

# Conflicts:
#	source/CMakeLists.txt

source/common/scripting/core/dictionary.h

@@ -0,0 +1,70 @@
+#pragma once
+
+#include "tarray.h"
+#include "zstring.h"
+#include "dobject.h"
+
+#include <memory>
+
+/**
+ * @brief The Dictionary class exists to be exported to ZScript.
+ *
+ * It is a string-to-string map.
+ *
+ * It is derived from DObject to be a part of normal GC process.
+ */
+class Dictionary final : public DObject
+{
+	DECLARE_CLASS(Dictionary, DObject)
+
+public:
+
+	using StringMap = TMap<FString, FString>;
+	using ConstIterator = StringMap::ConstIterator;
+	using ConstPair = StringMap::ConstPair;
+
+	void Serialize(FSerializer &arc) override;
+
+	StringMap Map;
+};
+
+/**
+ * @brief The DictionaryIterator class exists to be exported to ZScript.
+ *
+ * It provides iterating over a Dictionary. The order is not specified.
+ *
+ * It is derived from DObject to be a part of normal GC process.
+ */
+class DictionaryIterator final : public DObject
+{
+	DECLARE_CLASS(DictionaryIterator, DObject)
+	HAS_OBJECT_POINTERS
+
+public:
+
+	~DictionaryIterator() override = default;
+
+	/**
+	 * IMPLEMENT_CLASS macro needs a constructor without parameters.
+	 *
+	 * @see init().
+	 */
+	DictionaryIterator();
+
+	void Serialize(FSerializer &arc) override;
+
+	/**
+	 * @brief init function complements constructor.
+	 * @attention always call init after constructing DictionaryIterator.
+	 */
+	void init(Dictionary *dict);
+
+	std::unique_ptr<Dictionary::ConstIterator> Iterator;
+	Dictionary::ConstPair *Pair;
+
+	/**
+	 * @brief Dictionary attribute exists for holding a pointer to iterated
+	 * dictionary, so it is known by GC.
+	 */
+	Dictionary *Dict;
+};