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std/collections/map_entries.ts

Deno standard library
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// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.// This module is browser compatible.
/** * Applies the given transformer to all entries in the given record and returns * a new record containing the results. * * @example * ```ts * import { mapEntries } from "https://deno.land/std@$STD_VERSION/collections/map_entries.ts"; * import { assertEquals } from "https://deno.land/std@$STD_VERSION/testing/asserts.ts"; * * const usersById = { * "a2e": { name: "Kim", age: 22 }, * "dfe": { name: "Anna", age: 31 }, * "34b": { name: "Tim", age: 58 }, * } as const; * const agesByNames = mapEntries(usersById, ([id, { name, age }]) => [name, age]); * * assertEquals( * agesByNames, * { * "Kim": 22, * "Anna": 31, * "Tim": 58, * }, * ); * ``` */export function mapEntries<T, O>( record: Readonly<Record<string, T>>, transformer: (entry: [string, T]) => [string, O],): Record<string, O> { const ret: Record<string, O> = {}; const entries = Object.entries(record);
for (const entry of entries) { const [mappedKey, mappedValue] = transformer(entry);
ret[mappedKey] = mappedValue; }
return ret;}