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https://github.com/vector-im/element-web.git
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69ee8fd96a
* Add commercial licence and update config files * Update license in headers * Revert "Update license in headers" This reverts commit 7ed7949485e88889a9ffc8075a9df1f8e936777e. * Update only spdx id * Remove LicenseRef- from package.json LicenseRef- no longer allowed in npm v3 package.json This fixes the warning in the logs and failing build check.
49 lines
1.2 KiB
TypeScript
49 lines
1.2 KiB
TypeScript
/*
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Copyright 2024 New Vector Ltd.
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Copyright 2021 The Matrix.org Foundation C.I.C.
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SPDX-License-Identifier: AGPL-3.0-only OR GPL-3.0-only OR LicenseRef-Element-Commercial
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Please see LICENSE files in the repository root for full details.
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*/
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/**
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* Utility class for lazily getting a variable.
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*/
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export class LazyValue<T> {
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private val?: T;
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private prom?: Promise<T>;
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private done = false;
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public constructor(private getFn: () => Promise<T>) {}
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/**
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* Whether or not a cached value is present.
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*/
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public get present(): boolean {
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// we use a tracking variable just in case the final value is falsy
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return this.done;
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}
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/**
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* Gets the value without invoking a get. May be undefined until the
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* value is fetched properly.
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*/
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public get cachedValue(): T | undefined {
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return this.val;
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}
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/**
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* Gets a promise which resolves to the value, eventually.
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*/
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public get value(): Promise<T> {
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if (this.prom) return this.prom;
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this.prom = this.getFn();
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return this.prom.then((v) => {
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this.val = v;
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this.done = true;
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return v;
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});
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}
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}
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