Function: orThrough()

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

If the original result is a Success, it is returned immediately without running the function. If the original result is a Failure, the function is executed with the error value. If the function returns a Success, the original failure is returned. If the function returns a Failure, that new failure is returned.

Useful for running error recovery or fallback logic while preserving the original error on success.

Type Param

The input Result or ResultAsync.

Type Param

The result type returned by fn.

Examples

import { 
import Result
Result
} from '@praha/byethrow';
const
const result: Result.Result<5, never>
result
=
import Result
Result
.
const pipe: <Result.Result<5, never>, Result.Result<5, never>>(a: Result.Result<5, never>, ab: (a: Result.Result<5, never>) => Result.Result<5, never>) => Result.Result<5, never> (+25 overloads)
pipe
(
import Result
Result
.
const succeed: <5>(value: 5) => Result.Result<5, never> (+1 overload)
succeed
(5),
import Result
Result
.
const orThrough: <Result.Result<5, never>, Result.Result<null, never>>(fn: (a: never) => Result.Result<null, never>) => (result: Result.Result<5, never>) => Result.Result<5, never> (+1 overload)
orThrough
((
error: never
error
) => {
return
import Result
Result
.
const succeed: <null>(value: null) => Result.Result<null, never> (+1 overload)
succeed
(null);
}), ); // { type: 'Success', value: 5 }
import { 
import Result
Result
} from '@praha/byethrow';
const
const result: Result.Result<never, "error">
result
=
import Result
Result
.
const pipe: <Result.Result<never, "error">, Result.Result<never, "error">>(a: Result.Result<never, "error">, ab: (a: Result.Result<never, "error">) => Result.Result<never, "error">) => Result.Result<never, "error"> (+25 overloads)
pipe
(
import Result
Result
.
const fail: <"error">(error: "error") => Result.Result<never, "error"> (+1 overload)
fail
('error'),
import Result
Result
.
const orThrough: <Result.Result<never, "error">, Result.Result<null, never>>(fn: (a: "error") => Result.Result<null, never>) => (result: Result.Result<never, "error">) => Result.Result<never, "error"> (+1 overload)
orThrough
((
error: "error"
error
) => {
var console: Console

The console module provides a simple debugging console that is similar to the JavaScript console mechanism provided by web browsers.

The module exports two specific components:

  • A Console class with methods such as console.log(), console.error() and console.warn() that can be used to write to any Node.js stream.
  • A global console instance configured to write to process.stdout and process.stderr. The global console can be used without importing the node:console module.

Warning: The global console object's methods are neither consistently synchronous like the browser APIs they resemble, nor are they consistently asynchronous like all other Node.js streams. See the note on process I/O for more information.

Example using the global console:

console.log('hello world');
// Prints: hello world, to stdout
console.log('hello %s', 'world');
// Prints: hello world, to stdout
console.error(new Error('Whoops, something bad happened'));
// Prints error message and stack trace to stderr:
//   Error: Whoops, something bad happened
//     at [eval]:5:15
//     at Script.runInThisContext (node:vm:132:18)
//     at Object.runInThisContext (node:vm:309:38)
//     at node:internal/process/execution:77:19
//     at [eval]-wrapper:6:22
//     at evalScript (node:internal/process/execution:76:60)
//     at node:internal/main/eval_string:23:3

const name = 'Will Robinson';
console.warn(`Danger ${name}! Danger!`);
// Prints: Danger Will Robinson! Danger!, to stderr

Example using the Console class:

const out = getStreamSomehow();
const err = getStreamSomehow();
const myConsole = new console.Console(out, err);

myConsole.log('hello world');
// Prints: hello world, to out
myConsole.log('hello %s', 'world');
// Prints: hello world, to out
myConsole.error(new Error('Whoops, something bad happened'));
// Prints: [Error: Whoops, something bad happened], to err

const name = 'Will Robinson';
myConsole.warn(`Danger ${name}! Danger!`);
// Prints: Danger Will Robinson! Danger!, to err
@seesource
console
.
Console.log(message?: any, ...optionalParams: any[]): void (+1 overload)

Prints to stdout with newline. Multiple arguments can be passed, with the first used as the primary message and all additional used as substitution values similar to printf(3) (the arguments are all passed to util.format()).

const count = 5;
console.log('count: %d', count);
// Prints: count: 5, to stdout
console.log('count:', count);
// Prints: count: 5, to stdout

See util.format() for more information.

@sincev0 .1.100
log
('Logging error:',
error: "error"
error
);
return
import Result
Result
.
const succeed: <null>(value: null) => Result.Result<null, never> (+1 overload)
succeed
(null);
}), ); // { type: 'Failure', error: 'error' }
import { 
import Result
Result
} from '@praha/byethrow';
const
const result: Result.Result<never, "original error" | "new error">
result
=
import Result
Result
.
const pipe: <Result.Result<never, "original error">, Result.Result<never, "original error" | "new error">>(a: Result.Result<never, "original error">, ab: (a: Result.Result<never, "original error">) => Result.Result<never, "original error" | "new error">) => Result.Result<never, "original error" | "new error"> (+25 overloads)
pipe
(
import Result
Result
.
const fail: <"original error">(error: "original error") => Result.Result<never, "original error"> (+1 overload)
fail
('original error'),
import Result
Result
.
const orThrough: <Result.Result<never, "original error">, Result.Result<never, "new error">>(fn: (a: "original error") => Result.Result<never, "new error">) => (result: Result.Result<never, "original error">) => Result.Result<never, "original error" | "new error"> (+1 overload)
orThrough
((
error: "original error"
error
) => {
return
import Result
Result
.
const fail: <"new error">(error: "new error") => Result.Result<never, "new error"> (+1 overload)
fail
('new error');
}), ); // { type: 'Failure', error: 'new error' }

See

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

Call Signature

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

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

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

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<any, Parameters<F>[0]>

Parameters

result

R1

Returns

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