didier amyot
0d627c9051
The class was already implemented in "https://deno.land/std@0.144.0/streams/conversion.ts". So, I litterally lost 1 day of work! I hate myself.
22 lines
742 B
TypeScript
22 lines
742 B
TypeScript
// Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.
|
|
// This module is browser compatible.
|
|
|
|
/** 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).
|
|
*
|
|
* ```ts
|
|
* import { startsWith } from "https://deno.land/std@$STD_VERSION/bytes/starts_with.ts";
|
|
* const source = new Uint8Array([0, 1, 2, 1, 2, 1, 2, 3]);
|
|
* const prefix = new Uint8Array([0, 1, 2]);
|
|
* console.log(startsWith(source, prefix)); // true
|
|
* ```
|
|
*/
|
|
export function startsWith(source: Uint8Array, prefix: Uint8Array): boolean {
|
|
for (let i = 0, max = prefix.length; i < max; i++) {
|
|
if (source[i] !== prefix[i]) return false;
|
|
}
|
|
return true;
|
|
}
|