Map.groupBy type (#660)

penumbra-zone · Mar 4, 2024 · 2d68674 · 2d68674
1 parent 4b370de
commit 2d68674
Showing 1 changed file with 11 additions and 0 deletions.
diff --git a/packages/polyfills/Map.groupBy.ts b/packages/polyfills/Map.groupBy.ts
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+/** @see https://tc39.es/proposal-array-grouping/#sec-map.groupby */
+// already shipped in chrome, no type definition yet
+
+type MapGroupBy = <T, G>(
+  items: Iterable<T>,
+  callbackfn: (value: T, index: number) => G,
+) => Map<G, T[]>;
+
+type MapWithGroupBy = typeof Map & { groupBy: MapGroupBy };
+
+export default Map as MapWithGroupBy;