Refactor: optimize ArrayPoly.filterUniqueMapped() further (#1155)

emmercm · Jun 11, 2024 · ed1f267 · ed1f267
1 parent c08e57a
commit ed1f267
Showing 1 changed file with 7 additions and 10 deletions.
diff --git a/src/polyfill/arrayPoly.ts b/src/polyfill/arrayPoly.ts
@@ -28,17 +28,14 @@ export default class ArrayPoly {
   public static filterUniqueMapped<T, V>(
     mapper: (arg: T) => V,
   ): (value: T, idx: number, values: T[]) => boolean {
-    const mappedValues = new Map<V, number>();
-    return (value: T, idx: number, values: T[]): boolean => {
-      if (mappedValues.size === 0) {
-        values.forEach((val, valIdx) => {
-          const mapped = mapper(val);
-          if (!mappedValues.has(mapped)) {
-            mappedValues.set(mapped, valIdx);
-          }
-        });
+    const seenMappedValues = new Set<V>();
+    return (value: T): boolean => {
+      const mapped = mapper(value);
+      if (!seenMappedValues.has(mapped)) {
+        seenMappedValues.add(mapped);
+        return true;
       }
-      return mappedValues.get(mapper(value)) === idx;
+      return false;
     };
   }