Add HashMapKeys() and HashMapValues() functions for convenience.

Cytoplasm/src/HashMap.c

@@ -25,6 +25,7 @@
 
 #include <Memory.h>
 #include <Str.h>
+#include <Array.h>
 
 #include <stddef.h>
 #include <string.h>
@@ -399,3 +400,57 @@ HashMapIterateFree(char *key, void *value)
         Free(value);
     }
 }
+
+Array *
+HashMapKeys(HashMap * map)
+{
+    Array *arr;
+
+    char *key;
+    void *val;
+
+    if (!map)
+    {
+        return NULL;
+    }
+
+    arr = ArrayCreate();
+    if (!arr)
+    {
+        return NULL;
+    }
+
+    while (HashMapIterate(map, &key, &val))
+    {
+        ArrayAdd(arr, key);
+    }
+
+    return arr;
+}
+
+Array *
+HashMapValues(HashMap *map)
+{
+    Array *arr;
+
+    char *key;
+    void *val;
+
+    if (!map)
+    {
+        return NULL;
+    }
+
+    arr = ArrayCreate();
+    if (!arr)
+    {
+        return NULL;
+    }
+
+    while (HashMapIterate(map, &key, &val))
+    {
+        ArrayAdd(arr, val);
+    }
+
+    return arr;
+}

Cytoplasm/src/include/HashMap.h

@@ -46,6 +46,8 @@
 
 #include <stddef.h>
 
+#include <Array.h>
+
 /**
  * These functions operate on an opaque structure, which the caller
  * has no knowledge about.
@@ -164,4 +166,20 @@ extern int HashMapIterate(HashMap *, char **, void **);
 extern int
 HashMapIterateReentrant(HashMap *, char **, void **, size_t *);
 
+/**
+ * Collect the string keys of a hash map and return them as an array.
+ * The returned array holds pointers to the strings stored in the
+ * hash map, so the strings should NOT be freed; it is sufficient to
+ * free the array itself. Likewise, once the hash map is freed, the
+ * array elements are invalid and the array should be freed.
+ */
+extern Array * HashMapKeys(HashMap *);
+
+/**
+ * Collect the values of a hash map and return them as an array. The
+ * returned array holds the same pointers to the values as the hash
+ * map.
+ */
+extern Array * HashMapValues(HashMap *);
+
 #endif                             /* CYTOPLASM_HASHMAP_H */