Grabbed dndbeyond's source code

```
~/go/bin/sourcemapper -output ddb -jsurl https://media.dndbeyond.com/character-app/static/js/main.90aa78c5.js
```

ddb_main/packages/rules-engine/es/utils/ReduxActionUtils.js

@@ -0,0 +1,12 @@
+/**
+ *
+ * @param {function} actionCreator
+ * @param {...*} params
+ */
+export function callCommitAction(actionCreator, ...params) {
+    let action = actionCreator(...params);
+    return {
+        type: action.meta.commit.type,
+        payload: action.payload,
+    };
+}

ddb_main/packages/rules-engine/es/utils/SelectorHelpers.js

@@ -0,0 +1,4 @@
+export function getArrayOrNullFallback(value) {
+    let fallback = [];
+    return value === null ? fallback : value;
+}

ddb_main/packages/rules-engine/es/utils/TypeScriptUtils.js

@@ -0,0 +1,16 @@
+/**
+ * https://github.com/Microsoft/TypeScript/issues/16069#issuecomment-369374214
+ * Used to get around array filter function that errors because it doesn't recognize the filter
+ * is removing nulls
+ * @param input
+ */
+export function isNotNullOrUndefined(input) {
+    return input !== null;
+}
+/**
+ *
+ * @param x
+ */
+export function testUnreachable(x) {
+    // not implemented, only here for param check
+}