export dictionary iterator

src/utility/dictionary.cpp

@@ -11,7 +11,6 @@
 
 DEFINE_ACTION_FUNCTION(_Dictionary, Create)
 {
-	PARAM_PROLOGUE;
 	ACTION_RETURN_POINTER(new Dictionary);
 }
 
@@ -81,3 +80,64 @@ DEFINE_ACTION_FUNCTION_NATIVE(_Dictionary, Remove, DictRemove)
 	DictRemove(self, key);
 	return 0;
 }
+
+//=====================================================================================
+//
+// DictionaryIterator exports
+//
+//=====================================================================================
+
+DictionaryIterator::DictionaryIterator(const Dictionary &dict)
+	: Iterator(dict)
+	, Pair(nullptr)
+{
+}
+
+static DictionaryIterator *DictIteratorCreate(const Dictionary *dict)
+{
+	return new DictionaryIterator(*dict);
+}
+
+DEFINE_ACTION_FUNCTION_NATIVE(_DictionaryIterator, Create, DictIteratorCreate)
+{
+	PARAM_PROLOGUE;
+	PARAM_POINTER(dict, Dictionary);
+	ACTION_RETURN_POINTER(DictIteratorCreate(dict));
+}
+
+static int DictIteratorNext(DictionaryIterator *self)
+{
+	return self->Iterator.NextPair(self->Pair);
+}
+
+DEFINE_ACTION_FUNCTION_NATIVE(_DictionaryIterator, Next, DictIteratorNext)
+{
+	PARAM_SELF_STRUCT_PROLOGUE(DictionaryIterator);
+	ACTION_RETURN_BOOL(DictIteratorNext(self));
+}
+
+static void DictIteratorKey(const DictionaryIterator *self, FString *result)
+{
+	*result = self->Pair ? self->Pair->Key : FString {};
+}
+
+DEFINE_ACTION_FUNCTION_NATIVE(_DictionaryIterator, Key, DictIteratorKey)
+{
+	PARAM_SELF_STRUCT_PROLOGUE(DictionaryIterator);
+	FString result;
+	DictIteratorKey(self, &result);
+	ACTION_RETURN_STRING(result);
+}
+
+static void DictIteratorValue(const DictionaryIterator *self, FString *result)
+{
+	*result = self->Pair ? self->Pair->Value : FString {};
+}
+
+DEFINE_ACTION_FUNCTION_NATIVE(_DictionaryIterator, Value, DictIteratorValue)
+{
+	PARAM_SELF_STRUCT_PROLOGUE(DictionaryIterator);
+	FString result;
+	DictIteratorValue(self, &result);
+	ACTION_RETURN_STRING(result);
+}

src/utility/dictionary.h

@@ -4,3 +4,11 @@
 #include "zstring.h"
 
 using Dictionary = TMap<FString, FString>;
+
+struct DictionaryIterator
+{
+	explicit DictionaryIterator(const Dictionary &dict);
+
+	Dictionary::ConstIterator Iterator;
+	Dictionary::ConstPair *Pair;
+};

wadsrc/static/zscript/dictionary.zs

@@ -1,11 +1,50 @@
 struct Dictionary native
 {
 	native static Dictionary Create();
-	native static Dictionary FromString(String s);
 
 	native void Insert(String key, String value);
 	native void Remove(String key);
+
+	/**
+	 * Returns the value for the specified key.
+	 */
 	native String At(String key) const;
 
+	/**
+	 * Deserializes a dictionary from a string.
+	 *
+	 * @param s serialized string, must be either empty or returned from ToString().
+	 */
+	native static Dictionary FromString(String s);
+
+	/**
+	 * Serializes a dictionary to a string.
+	 */
 	native String ToString() const;
 }
+
+struct DictionaryIterator native
+{
+	native static DictionaryIterator Create(Dictionary dict);
+
+	/**
+	 * Returns false if there are no more entries in the dictionary.
+	 * Otherwise, returns true.
+	 *
+	 * While it returns true, get key and value for the current entry
+	 * with Key() and Value() functions.
+	 */
+	native bool Next();
+
+	/**
+	 * Returns the key for the current dictionary entry.
+	 * Do not call this function before calling Next().
+	 */
+	native String Key() const;
+
+	/**
+	 * Returns the value for the current dictionary entry.
+	 * Do not call this function before calling Next().
+	 */
+	native String Value() const;
+}