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Module

std/bytes/mod.ts>startsWith

The Deno Standard Library
Latest
function startsWith
import { startsWith } from "https://deno.land/std@0.224.0/bytes/mod.ts";

Returns true if the prefix array appears at the start of the source array, false otherwise.

The complexity of this function is O(prefix.length).

Examples

Basic usage

import { startsWith } from "https://deno.land/std@0.224.0/bytes/starts_with.ts";

const source = new Uint8Array([0, 1, 2, 1, 2, 1, 2, 3]);
const prefix = new Uint8Array([0, 1, 2]);

startsWith(source, prefix); // true

Parameters

source: Uint8Array

Source array to check.

prefix: Uint8Array

Prefix array to check for.

Returns

boolean

true if the prefix array appears at the start of the source array, false otherwise.