#Function: andThen()

Chains the next computation using the success value of a Result or ResultAsync. If the original result is a Failure, it is returned unchanged. Otherwise, the provided function is called, and its result is returned as-is.

#Type Param

The input Result or ResultAsync.

#Type Param

The result type returned by fn.

#Examples

import { Result } from '@praha/byethrow';

const result = Result.pipe(
  Result.succeed(3),
  Result.andThen((x) => Result.succeed(x * 2)),
);
// { type: 'Success', value: 6 }

const result = Result.pipe(
  Result.fail('error'),
  Result.andThen((x) => Result.succeed(x * 2)),
);
// result: { type: 'Failure', error: 'error' }

const result = Result.pipe(
  Result.succeed(3),
  Result.andThen((x) => Result.fail('error: ' + x)),
);
// result: { type: 'Failure', error: 'error: 3' }

#See

pipe - It is recommended to use this function with the pipe function for better readability and composability.

#Call Signature

andThen<R1, R2>(fn): (result) => ResultFor<R1 | R2, InferSuccess<R2>, InferFailure<R1> | InferFailure<R2>>

Defined in: functions/and-then.ts:51

#Type Parameters

#R1

R1 extends ResultMaybeAsync<any, any>

#R2

R2 extends ResultMaybeAsync<any, any>

#Parameters

#fn

(a) => R2

#Returns

(result): ResultFor<R1 | R2, InferSuccess<R2>, InferFailure<R1> | InferFailure<R2>>

#Parameters

#result

R1

#Returns

ResultFor<R1 | R2, InferSuccess<R2>, InferFailure<R1> | InferFailure<R2>>

#Call Signature

andThen<F>(fn): <R1>(result) => ResultFor<R1 | ReturnType<F>, InferSuccess<F>, InferFailure<R1> | InferFailure<F>>

Defined in: functions/and-then.ts:52

#Type Parameters

#F

F extends (a) => ResultMaybeAsync<any, any>

#Parameters

#fn

F

#Returns

<R1>(result): ResultFor<R1 | ReturnType<F>, InferSuccess<F>, InferFailure<R1> | InferFailure<F>>

#Type Parameters

#R1

R1 extends ResultMaybeAsync<Parameters<F>[0], any>

#Parameters

#result

R1

#Returns

ResultFor<R1 | ReturnType<F>, InferSuccess<F>, InferFailure<R1> | InferFailure<F>>