20 lines
307 B
TypeScript
20 lines
307 B
TypeScript
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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