#Function: andThrough()

Runs an additional computation using the success value of a Result or ResultAsync, but returns the original result if the additional computation is successful.

If either the original result or the side effect result is a Failure, that failure is returned. Useful for running validations or side effects without altering the main result on success.

#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(5),
  Result.andThrough((x) => {
    return x > 0 ? Result.succeed(null) : Result.fail('Must be > 0');
  }),
);
// { type: 'Success', value: 5 }

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

const result = Result.pipe(
  Result.fail('error),
  Result.andThrough((x) => {
    return x > 0 ? Result.succeed(null) : Result.fail('Must be > 0');
  }),
);
// { type: 'Failure', error: 'error' }

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

const result = Result.pipe(
  Result.succeed(-10),
  Result.andThrough((x) => {
    return x > 0 ? Result.succeed(null) : Result.fail('Must be > 0');
  }),
);
// { type: 'Failure', error: 'Must be > 0' }

#See

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

#Call Signature

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

Defined in: functions/and-through.ts:63

#Type Parameters

#R1

R1 extends ResultMaybeAsync<any, any>

#R2

R2 extends ResultMaybeAsync<any, any>

#Parameters

#fn

(a) => R2

#Returns

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

#Parameters

#result

R1

#Returns

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

#Call Signature

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

Defined in: functions/and-through.ts:64

#Type Parameters

#F

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

#Parameters

#fn

F

#Returns

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

#Type Parameters

#R1

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

#Parameters

#result

R1

#Returns

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