Function flatMap

flatMap<T, U, E, F>(
result: Result<T, E>,
fn: (value: T) => Result<U, F>,
): Result<U, E | F>
Canonical bind (Fantasy Land chain). Chains a Result-returning step, widening the error union to E | F. Short-circuits on Err.
Type Parameters
- T
- U
- E
- F
Parameters
- result: Result<T, E>
- fn: (value: T) => Result<U, F>
Returns Result<U, E | F>
Example
```
flatMap(parseInput(raw), (data) =>
  data.id != null ? ok(data) : err({ kind: "missing_id" as const }),
);
// Result<Data, ParseError | { kind: "missing_id" }>
```
- Defined in packages/result/src/result.ts:167
flatMap<T, U, F>(
fn: (value: T) => Result<U, F>,
): <E>(result: Result<T, E>) => Result<U, F | E>
Canonical bind (Fantasy Land chain). Chains a Result-returning step, widening the error union to E | F. Short-circuits on Err.
Type Parameters
- T
- U
- F
Parameters
- fn: (value: T) => Result<U, F>
Returns <E>(result: Result<T, E>) => Result<U, F | E>
Example
```
flatMap(parseInput(raw), (data) =>
  data.id != null ? ok(data) : err({ kind: "missing_id" as const }),
);
// Result<Data, ParseError | { kind: "missing_id" }>
```
- Defined in packages/result/src/result.ts:171