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std/collections/map_values.ts

Deno standard library
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// Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.// This module is browser compatible.
/** * Applies the given transformer to all values in the given record and returns a * new record containing the resulting keys associated to the last value that * produced them. * * @example * ```ts * import { mapValues } from "https://deno.land/std@$STD_VERSION/collections/map_values.ts"; * import { assertEquals } from "https://deno.land/std@$STD_VERSION/testing/asserts.ts"; * * const usersById = { * "a5ec": { name: "Mischa" }, * "de4f": { name: "Kim" }, * }; * const namesById = mapValues(usersById, (it) => it.name); * * assertEquals( * namesById, * { * "a5ec": "Mischa", * "de4f": "Kim", * }, * ); * ``` */export function mapValues<T, O>( record: Readonly<Record<string, T>>, transformer: (value: T) => O,): Record<string, O> { const ret: Record<string, O> = {}; const entries = Object.entries(record);
for (const [key, value] of entries) { const mappedValue = transformer(value);
ret[key] = mappedValue; }
return ret;}