| 1 | // Copyright (c) Jupyter Development Team.
|
| 2 | // Distributed under the terms of the Modified BSD License.
|
| 3 | /*-----------------------------------------------------------------------------
|
| 4 | | Copyright (c) 2014-2017, PhosphorJS Contributors
|
| 5 | |
|
| 6 | | Distributed under the terms of the BSD 3-Clause License.
|
| 7 | |
|
| 8 | | The full license is in the file LICENSE, distributed with this software.
|
| 9 | |----------------------------------------------------------------------------*/
|
| 10 |
|
| 11 | /**
|
| 12 | * A class which wraps a promise into a delegate object.
|
| 13 | *
|
| 14 | * #### Notes
|
| 15 | * This class is useful when the logic to resolve or reject a promise
|
| 16 | * cannot be defined at the point where the promise is created.
|
| 17 | */
|
| 18 | export class PromiseDelegate<T> {
|
| 19 | /**
|
| 20 | * Construct a new promise delegate.
|
| 21 | */
|
| 22 | constructor() {
|
| 23 | this.promise = new Promise<T>((resolve, reject) => {
|
| 24 | this._resolve = resolve;
|
| 25 | this._reject = reject;
|
| 26 | });
|
| 27 | }
|
| 28 |
|
| 29 | /**
|
| 30 | * The promise wrapped by the delegate.
|
| 31 | */
|
| 32 | readonly promise: Promise<T>;
|
| 33 |
|
| 34 | /**
|
| 35 | * Resolve the wrapped promise with the given value.
|
| 36 | *
|
| 37 | * @param value - The value to use for resolving the promise.
|
| 38 | */
|
| 39 | resolve(value: T | PromiseLike<T>): void {
|
| 40 | let resolve = this._resolve;
|
| 41 | resolve(value);
|
| 42 | }
|
| 43 |
|
| 44 | /**
|
| 45 | * Reject the wrapped promise with the given value.
|
| 46 | *
|
| 47 | * @reason - The reason for rejecting the promise.
|
| 48 | */
|
| 49 | reject(reason: unknown): void {
|
| 50 | let reject = this._reject;
|
| 51 | reject(reason);
|
| 52 | }
|
| 53 |
|
| 54 | private _resolve: (value: T | PromiseLike<T>) => void;
|
| 55 | private _reject: (reason: any) => void;
|
| 56 | }
|