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@std/collections@0.215.0

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It is unknown whether this package works with Browsers
It is unknown whether this package works with Deno
It is unknown whether this package works with Node.js
It is unknown whether this package works with Cloudflare Workers
It is unknown whether this package works with Bun
•JSR Score70%•
Downloads1/wk
•
Published2 years ago (0.215.0)
function reduceGroups
reduceGroups<T, A>(
record: Readonly<Record<string, ReadonlyArray<T>>>,
reducer: (
accumulator: A,
current: T
) => A,
initialValue: A
): Record<string, A>

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 "@std/collections/reduce_groups";
import { assertEquals } from "@std/assert/assert_equals";

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,
});

Type Parameters

T

input type of an item in a group in the given grouping.

A

type of the accumulator value, which will match the returned record's values.

Parameters

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

Return Type

Record<string, A>

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Add Package

deno add jsr:@std/collections

Import symbol

import { reduceGroups } from "@std/collections";
or

Import directly with a jsr specifier

import { reduceGroups } from "jsr:@std/collections";