Files
openstapps/packages/collection-utils/src/key-by.js

31 lines
1.2 KiB
JavaScript

/*
* Copyright (C) 2022 StApps
* This program is free software: you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
* Software Foundation, version 3.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program. If not, see <https://www.gnu.org/licenses/>.
*/
/**
* Create an object composed of keys generated from the results of running each element of collection through iteratee.
* The corresponding value of each key is the last element responsible for generating the key.
* The iteratee is invoked with one argument: (value).
* @template T
* @param collection {T[]}
* @param key {(item: T) => string | number}
* @returns {Record<string, T>}
*/
export function keyBy(collection, key) {
return collection.reduce((accumulator, item) => {
accumulator[key(item)] = item;
return accumulator;
}, /** @type {Record<string, T>} */ ({}));
}