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function reduceGroups
import { reduceGroups } from "https://deno.land/std@0.167.0/collections/mod.ts";

Applies the given reducer to each group in the given Grouping, returning the results together with the respective group keys.

Examples

Example 1

import { reduceGroups } from "https://deno.land/std@0.167.0/collections/reduce_groups.ts";
import { assertEquals } from "https://deno.land/std@0.167.0/testing/asserts.ts";

const votes = {
  "Woody": [2, 3, 1, 4],
  "Buzz": [5, 9],
};

const totalVotes = reduceGroups(votes, (sum, it) => sum + it, 0);

assertEquals(totalVotes, {
  "Woody": 10,
  "Buzz": 14,
});

Parameters

record: Readonly<Record<string, Array<T>>>
reducer: (accumulator: A, current: T) => A
initialValue: A

Returns

Record<string, A>