fix(core): update

ts/index.ts

@@ -1,3 +1,17 @@
+export const map = async <T = any, R = any>(
+  arrayArg: T[],
+  mapFunction: (itemArg: T) => Promise<R>
+): Promise<R[]> => {
+  const returnArray: R[] = [];
+  for (const itemArg of arrayArg) {
+    const mapResult = await mapFunction(itemArg);
+    if (mapResult !== undefined) {
+      returnArray.push(mapResult);
+    }
+  }
+  return returnArray;
+};
+
 export const filter = async <T>(
   arrayArg: T[],
   filterFunction: (itemArg: T) => Promise<boolean>