update readme

Author: theKashey

README.md

@@ -434,6 +434,24 @@ const MyPage = () => (
 );
 ```
 
+## Webpack integration (experimental)
+
+```js
+// get mark somehow
+import {getMarkedChunks} from 'react-imported-component/server';
+
+const chunkNames = getMarkedChunks(marks); 
+
+// use flush-webpack-chunks to discover assets behind chunk name
+```
+
+## React-snap
+`react-imported-component` is the only (even) theoretically compatible loader for [react-snap](https://github.com/stereobooster/react-snap).
+
+
+## Webpack-external-import
+`react-imported-component` is the only (even) theoretically compatible loader for [webpack-external-import](https://github.com/ScriptedAlchemy/webpack-external-import).
+
 ## SSR (Server side rendering)
 It was usually a headache - async components and SSR, which is currently sync.
 React-imported-component break this cycle, making ServerSide rendering sync, and providing

src/markerMapper.ts

@@ -2,14 +2,18 @@ import {Mark, MarkMeta} from "./types";
 import {markMeta} from "./loadable";
 import {markerOverlap} from "./marks";
 
-const getMarkedMeta = (marks: Mark, mapping: (meta: MarkMeta) => string) => (
-  (new Set(
+const getMarkedMeta = (marks: Mark, mapping: (meta: MarkMeta) => string) => {
+  if (markMeta.length === 0) {
+    throw new Error('react-imported-component: no import meta-information found. Have you imported async-requires?');
+  }
+
+  return Array.from(new Set(
     markMeta
       .filter(meta => markerOverlap(meta.mark, marks))
       .map(mapping)
       .filter(Boolean)
-  )).values()
-);
+  ).values());
+};
 
 export const getMarkedChunks = (marks: Mark) => getMarkedMeta(marks, meta => meta.chunkName);
 export const getMarkedFileNames = (marks: Mark) => getMarkedMeta(marks, meta => meta.fileName);