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std/collections/sort_by.ts

Deno standard library
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// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.// This module is browser compatible.
/** * Returns all elements in the given collection, sorted stably by their result using the given selector. The selector function is called only once for each element. * * Example: * * ```ts * import { sortBy } from "https://deno.land/std@$STD_VERSION/collections/mod.ts" * import { assertEquals } from "https://deno.land/std@$STD_VERSION/testing/asserts.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 }, * ]) * ``` */export function sortBy<T>( array: readonly T[], selector: ((el: T) => number),): T[];export function sortBy<T>( array: readonly T[], selector: ((el: T) => string),): T[];export function sortBy<T>( array: readonly T[], selector: ((el: T) => bigint),): T[];export function sortBy<T>( array: readonly T[], selector: ((el: T) => Date),): T[];export function sortBy<T>( array: readonly T[], selector: | ((el: T) => number) | ((el: T) => string) | ((el: T) => bigint) | ((el: T) => Date),): T[] { const len = array.length; const indexes = new Array<number>(len); const selectors = new Array<ReturnType<typeof selector> | null>(len);
for (let i = 0; i < len; i++) { indexes[i] = i; const s = selector(array[i]); selectors[i] = Number.isNaN(s) ? null : s; }
indexes.sort((ai, bi) => { const a = selectors[ai]; const b = selectors[bi]; 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]]; }
return indexes as unknown as T[];}