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std/collections/sort_by.ts

The Deno Standard Library
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// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.// This module is browser compatible.
/** Order option for {@linkcode SortByOptions}. */export type Order = "asc" | "desc";
/** Options for {@linkcode sortBy}. */export type SortByOptions = { order: Order;};
/** * Returns all elements in the given collection, sorted by their result using * the given selector. The selector function is called only once for each * element. Ascending or descending order can be specified. * * @example * ```ts * import { sortBy } from "https://deno.land/std@$STD_VERSION/collections/sort_by.ts"; * import { assertEquals } from "https://deno.land/std@$STD_VERSION/assert/assert_equals.ts"; * * const people = [ * { name: "Anna", age: 34 }, * { name: "Kim", age: 42 }, * { name: "John", age: 23 }, * ]; * const sortedByAge = sortBy(people, (it) => it.age); * * assertEquals(sortedByAge, [ * { name: "John", age: 23 }, * { name: "Anna", age: 34 }, * { name: "Kim", age: 42 }, * ]); * * const sortedByAgeDesc = sortBy(people, (it) => it.age, { order: "desc" }); * * assertEquals(sortedByAgeDesc, [ * { name: "Kim", age: 42 }, * { name: "Anna", age: 34 }, * { name: "John", age: 23 }, * ]); * ``` */export function sortBy<T>( array: readonly T[], selector: (el: T) => number, options?: SortByOptions,): T[];/** * Returns all elements in the given collection, sorted by their result using * the given selector. The selector function is called only once for each * element. Ascending or descending order can be specified. * * @example * ```ts * import { sortBy } from "https://deno.land/std@$STD_VERSION/collections/sort_by.ts"; * * const people = [ * { name: "Anna" }, * { name: "Kim" }, * { name: "John" }, * ]; * const sortedByName = sortBy(people, (it) => it.name); */export function sortBy<T>( array: readonly T[], selector: (el: T) => string, options?: SortByOptions,): T[];/** * Returns all elements in the given collection, sorted by their result using * the given selector. The selector function is called only once for each * element. Ascending or descending order can be specified. * * @example * ```ts * import { sortBy } from "https://deno.land/std@$STD_VERSION/collections/sort_by.ts"; * * const people = [ * { name: "Anna", age: 34n }, * { name: "Kim", age: 42n }, * { name: "John", age: 23n }, * ]; * const sortedByAge = sortBy(people, (it) => it.age); * ``` */
export function sortBy<T>( array: readonly T[], selector: (el: T) => bigint, options?: SortByOptions,): T[];/** * Returns all elements in the given collection, sorted by their result using * the given selector. The selector function is called only once for each * element. Ascending or descending order can be specified. * * @example * ```ts * import { sortBy } from "https://deno.land/std@$STD_VERSION/collections/sort_by.ts"; * * const people = [ * { name: "Anna", startedAt: new Date("2020-01-01") }, * { name: "Kim", startedAt: new Date("2020-03-01") }, * { name: "John", startedAt: new Date("2020-06-01") }, * ]; * const sortedByStartedAt = sortBy(people, (it) => it.startedAt); * ``` */export function sortBy<T>( array: readonly T[], selector: (el: T) => Date, options?: SortByOptions,): T[];export function sortBy<T>( array: readonly T[], selector: | ((el: T) => number) | ((el: T) => string) | ((el: T) => bigint) | ((el: T) => Date), options?: SortByOptions,): T[] { const len = array.length; const indexes = new Array<number>(len); const selectors = new Array<ReturnType<typeof selector> | null>(len); const order = options?.order ?? "asc";
array.forEach((item, idx) => { indexes[idx] = idx; const s = selector(item); selectors[idx] = Number.isNaN(s) ? null : s; });
indexes.sort((ai, bi) => { let a = selectors[ai]!; let b = selectors[bi]!; if (order === "desc") { [a, b] = [b, a]; } if (a === null) return 1; if (b === null) return -1; return a > b ? 1 : a < b ? -1 : 0; });
for (let i = 0; i < len; i++) { (indexes as unknown as T[])[i] = array[indexes[i] as number] as T; }
return indexes as unknown as T[];}