Switch values to having their data refcounted separately.

This allows for values to be "cast" and have a different type, while
still referencing the same data.

src/value.c

@@ -1,17 +1,27 @@
 #include "value.h"
 #include "parsetype.h"
 
-void libab_value_init(libab_value* value, void* data, libab_ref* type) {
-    value->data = data;
+void libab_value_init_ref(libab_value* value, libab_ref* data, libab_ref* type) {
+    libab_ref_copy(data, &value->data);
     libab_ref_copy(type, &value->type);
 }
 
-void libab_value_free(libab_value* value) {
-    void (*free_function)(void*);
-    libab_parsetype* value_type;
-    value_type = libab_ref_get(&value->type);
-    free_function = value_type->data_u.base->free_function;
-    libab_ref_free(&value->type);
-    if (free_function)
-        free_function(value->data);
+libab_result libab_value_init_raw(libab_value* value, void* data, libab_ref* type) {
+    libab_result result = LIBAB_SUCCESS;
+    libab_ref tmp_ref;
+
+    result = libab_ref_new(&tmp_ref, data, 
+            ((libab_parsetype*) libab_ref_get(type))->data_u.base->free_function);
+
+    if(result == LIBAB_SUCCESS) {
+        libab_value_init_ref(value, &tmp_ref, type);
+        libab_ref_free(&tmp_ref);
+    }
+
+    return result;
+}
+
+void libab_value_free(libab_value* value) {
+    libab_ref_free(&value->data);
+    libab_ref_free(&value->type);
 }