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- /**
- * **This module is pending deprecation.** Once a replacement API has been
- * finalized, this module will be fully deprecated. Most developers should
- * **not** have cause to use this module. Users who absolutely must have
- * the functionality that domains provide may rely on it for the time being
- * but should expect to have to migrate to a different solution
- * in the future.
- *
- * Domains provide a way to handle multiple different IO operations as a
- * single group. If any of the event emitters or callbacks registered to a
- * domain emit an `'error'` event, or throw an error, then the domain object
- * will be notified, rather than losing the context of the error in the `process.on('uncaughtException')` handler, or causing the program to
- * exit immediately with an error code.
- * @deprecated Since v1.4.2 - Deprecated
- * @see [source](https://github.com/nodejs/node/blob/v22.x/lib/domain.js)
- */
- declare module "domain" {
- import EventEmitter = require("node:events");
- /**
- * The `Domain` class encapsulates the functionality of routing errors and
- * uncaught exceptions to the active `Domain` object.
- *
- * To handle the errors that it catches, listen to its `'error'` event.
- */
- class Domain extends EventEmitter {
- /**
- * An array of timers and event emitters that have been explicitly added
- * to the domain.
- */
- members: Array<EventEmitter | NodeJS.Timer>;
- /**
- * The `enter()` method is plumbing used by the `run()`, `bind()`, and `intercept()` methods to set the active domain. It sets `domain.active` and `process.domain` to the domain, and implicitly
- * pushes the domain onto the domain
- * stack managed by the domain module (see {@link exit} for details on the
- * domain stack). The call to `enter()` delimits the beginning of a chain of
- * asynchronous calls and I/O operations bound to a domain.
- *
- * Calling `enter()` changes only the active domain, and does not alter the domain
- * itself. `enter()` and `exit()` can be called an arbitrary number of times on a
- * single domain.
- */
- enter(): void;
- /**
- * The `exit()` method exits the current domain, popping it off the domain stack.
- * Any time execution is going to switch to the context of a different chain of
- * asynchronous calls, it's important to ensure that the current domain is exited.
- * The call to `exit()` delimits either the end of or an interruption to the chain
- * of asynchronous calls and I/O operations bound to a domain.
- *
- * If there are multiple, nested domains bound to the current execution context, `exit()` will exit any domains nested within this domain.
- *
- * Calling `exit()` changes only the active domain, and does not alter the domain
- * itself. `enter()` and `exit()` can be called an arbitrary number of times on a
- * single domain.
- */
- exit(): void;
- /**
- * Run the supplied function in the context of the domain, implicitly
- * binding all event emitters, timers, and low-level requests that are
- * created in that context. Optionally, arguments can be passed to
- * the function.
- *
- * This is the most basic way to use a domain.
- *
- * ```js
- * import domain from 'node:domain';
- * import fs from 'node:fs';
- * const d = domain.create();
- * d.on('error', (er) => {
- * console.error('Caught error!', er);
- * });
- * d.run(() => {
- * process.nextTick(() => {
- * setTimeout(() => { // Simulating some various async stuff
- * fs.open('non-existent file', 'r', (er, fd) => {
- * if (er) throw er;
- * // proceed...
- * });
- * }, 100);
- * });
- * });
- * ```
- *
- * In this example, the `d.on('error')` handler will be triggered, rather
- * than crashing the program.
- */
- run<T>(fn: (...args: any[]) => T, ...args: any[]): T;
- /**
- * Explicitly adds an emitter to the domain. If any event handlers called by
- * the emitter throw an error, or if the emitter emits an `'error'` event, it
- * will be routed to the domain's `'error'` event, just like with implicit
- * binding.
- *
- * This also works with timers that are returned from `setInterval()` and `setTimeout()`. If their callback function throws, it will be caught by
- * the domain `'error'` handler.
- *
- * If the Timer or `EventEmitter` was already bound to a domain, it is removed
- * from that one, and bound to this one instead.
- * @param emitter emitter or timer to be added to the domain
- */
- add(emitter: EventEmitter | NodeJS.Timer): void;
- /**
- * The opposite of {@link add}. Removes domain handling from the
- * specified emitter.
- * @param emitter emitter or timer to be removed from the domain
- */
- remove(emitter: EventEmitter | NodeJS.Timer): void;
- /**
- * The returned function will be a wrapper around the supplied callback
- * function. When the returned function is called, any errors that are
- * thrown will be routed to the domain's `'error'` event.
- *
- * ```js
- * const d = domain.create();
- *
- * function readSomeFile(filename, cb) {
- * fs.readFile(filename, 'utf8', d.bind((er, data) => {
- * // If this throws, it will also be passed to the domain.
- * return cb(er, data ? JSON.parse(data) : null);
- * }));
- * }
- *
- * d.on('error', (er) => {
- * // An error occurred somewhere. If we throw it now, it will crash the program
- * // with the normal line number and stack message.
- * });
- * ```
- * @param callback The callback function
- * @return The bound function
- */
- bind<T extends Function>(callback: T): T;
- /**
- * This method is almost identical to {@link bind}. However, in
- * addition to catching thrown errors, it will also intercept `Error` objects sent as the first argument to the function.
- *
- * In this way, the common `if (err) return callback(err);` pattern can be replaced
- * with a single error handler in a single place.
- *
- * ```js
- * const d = domain.create();
- *
- * function readSomeFile(filename, cb) {
- * fs.readFile(filename, 'utf8', d.intercept((data) => {
- * // Note, the first argument is never passed to the
- * // callback since it is assumed to be the 'Error' argument
- * // and thus intercepted by the domain.
- *
- * // If this throws, it will also be passed to the domain
- * // so the error-handling logic can be moved to the 'error'
- * // event on the domain instead of being repeated throughout
- * // the program.
- * return cb(null, JSON.parse(data));
- * }));
- * }
- *
- * d.on('error', (er) => {
- * // An error occurred somewhere. If we throw it now, it will crash the program
- * // with the normal line number and stack message.
- * });
- * ```
- * @param callback The callback function
- * @return The intercepted function
- */
- intercept<T extends Function>(callback: T): T;
- }
- function create(): Domain;
- }
- declare module "node:domain" {
- export * from "domain";
- }
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