18 lines
510 B
TypeScript
18 lines
510 B
TypeScript
export type Result<A, E> = { tag: "ok"; value: A } | { tag: "error"; error: E }
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export const Result = {
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ok<A>(value: A): Result<A, never> {
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return { tag: "ok", value }
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},
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err<E>(error: E): Result<never, E> {
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return { tag: "error", error }
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},
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map<A, B, E>(result: Result<A, E>, f: (x: A) => B): Result<B, E> {
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switch (result.tag) {
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case "ok":
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return { tag: "ok", value: f(result.value) }
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case "error":
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return { tag: "error", error: result.error }
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}
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},
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}
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