typedash/dist/groupBy-CTfqrrae.cjs.map

modern, type-safe collection of utility functions

{"version":3,"file":"groupBy-CTfqrrae.cjs","names":[],"sources":["../src/functions/groupBy/groupBy.ts"],"sourcesContent":["import type { Maybe } from '../../types';\n\n/**\n * Takes an array and returns an object with the keys of the array mapped to the items of the array.\n * @param array The array to iterate over.\n * @param getter The function used to extract the key from each element.\n * @returns An object with the keys mapped to the elements.\n * @example\n * ```ts\n * groupBy(\n *   [\n *     { id: 'a', value: 1 },\n *     { id: 'b', value: 1 },\n *     { id: 'c', value: 2 },\n *   ],\n *   (item) => item.value\n * )\n * // {\n * //   1: [\n * //     { id: 'a', value: 1 },\n * //     { id: 'b', value: 1 },\n * //   ],\n * //   2: [\n * //     { id: 'c', value: 2 },\n * //   ],\n * // }\n * ```\n */\nexport function groupBy<T, K extends string>(\n  array: Maybe<readonly T[]>,\n  getter: (item: T) => K\n): Partial<Record<K, T[]>> {\n  return (array ?? []).reduce(\n    (draftGroups, currentItem) => {\n      const key = getter(currentItem);\n\n      draftGroups[key] ??= [];\n      // biome-ignore lint/style/noNonNullAssertion: surely exists because of the line above\n      draftGroups[key]!.push(currentItem);\n\n      return draftGroups;\n    },\n    {} as Partial<Record<K, T[]>>\n  );\n}\n"],"mappings":";;;;;;;;;;;;;;;;;;;;;;;;;;;;AA4BA,SAAgB,QACd,OACA,QACyB;AACzB,SAAQ,SAAS,EAAE,EAAE,QAClB,aAAa,gBAAgB;EAC5B,MAAM,MAAM,OAAO,YAAY;AAE/B,cAAY,SAAS,EAAE;AAEvB,cAAY,KAAM,KAAK,YAAY;AAEnC,SAAO;IAET,EAAE,CACH"}