26 lines
411 B
TypeScript
26 lines
411 B
TypeScript
/*
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* SPDX-FileCopyrightText: syuilo and misskey-project
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* SPDX-License-Identifier: AGPL-3.0-only
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*/
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export interface IMaybe<T> {
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isJust(): this is IJust<T>;
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}
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export interface IJust<T> extends IMaybe<T> {
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get(): T;
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}
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export function just<T>(value: T): IJust<T> {
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return {
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isJust: () => true,
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get: () => value,
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};
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}
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export function nothing<T>(): IMaybe<T> {
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return {
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isJust: () => false,
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};
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}
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