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Module

std/fs/exists.ts

Deno standard library
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The Standard Library has been moved to JSR. See the blog post for details.
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// Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.
/** * Test whether or not the given path exists by checking with the file system. * * Note: do not use this function if performing a check before another operation on that file. Doing so creates a race condition. Instead, perform the actual file operation directly. * * Bad: * ```ts * import { exists } from "https://deno.land/std@$STD_VERSION/fs/mod.ts"; * * if (await exists("./foo.txt")) { * await Deno.remove("./foo.txt"); * } * ``` * * Good: * ```ts * // Notice no use of exists * try { * await Deno.remove("./foo.txt"); * } catch (error) { * if (!(error instanceof Deno.errors.NotFound)) { * throw error; * } * // Do nothing... * } * ``` * @see https://en.wikipedia.org/wiki/Time-of-check_to_time-of-use * @deprecated (will be removed after 0.157.0) Checking the state of a file before using it causes a race condition. Perform the actual operation directly instead. */export async function exists(filePath: string | URL): Promise<boolean> { try { await Deno.lstat(filePath); return true; } catch (error) { if (error instanceof Deno.errors.NotFound) { return false; } throw error; }}
/** * Test whether or not the given path exists by checking with the file system. * * Note: do not use this function if performing a check before another operation on that file. Doing so creates a race condition. Instead, perform the actual file operation directly. * * Bad: * ```ts * import { existsSync } from "https://deno.land/std@$STD_VERSION/fs/mod.ts"; * * if (existsSync("./foo.txt")) { * Deno.removeSync("./foo.txt"); * } * ``` * * Good: * ```ts * // Notice no use of existsSync * try { * Deno.removeSync("./foo.txt"); * } catch (error) { * if (!(error instanceof Deno.errors.NotFound)) { * throw error; * } * // Do nothing... * } * ``` * @see https://en.wikipedia.org/wiki/Time-of-check_to_time-of-use * @deprecated (will be removed after 0.157.0) Checking the state of a file before using it causes a race condition. Perform the actual operation directly instead. */export function existsSync(filePath: string | URL): boolean { try { Deno.lstatSync(filePath); return true; } catch (error) { if (error instanceof Deno.errors.NotFound) { return false; } throw error; }}