Module

std/collections/mod.ts>distinctBy

Deno standard library
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function distinctBy
import { distinctBy } from "https://deno.land/std@0.167.0/collections/mod.ts";

Returns all elements in the given array that produce a distinct value using the given selector, preserving order by first occurrence.

Examples

Example 1

import { distinctBy } from "https://deno.land/std@0.167.0/collections/distinct_by.ts";
import { assertEquals } from "https://deno.land/std@0.167.0/testing/asserts.ts";

const names = ["Anna", "Kim", "Arnold", "Kate"];
const exampleNamesByFirstLetter = distinctBy(names, (it) => it.charAt(0));

assertEquals(exampleNamesByFirstLetter, ["Anna", "Kim"]);

Parameters

array: readonly T[]
selector: (el: T) => D