Class ResultTErrorMapErrorExtensions

Namespace

REslava.Result.Extensions

Assembly

REslava.Result.dll

MapError overload for Result<TValue, TError> typed pipelines. Translates the error surface without touching the success value.

public static class ResultTErrorMapErrorExtensions

Inheritance

object

ResultTErrorMapErrorExtensions

Inherited Members

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

object.ReferenceEquals(object, object)

object.ToString()

Methods

MapError<TValue, TErrorIn, TErrorOut>(Result<TValue, TErrorIn>, Func<TErrorIn, TErrorOut>)

Applies mapper to the error when the result is a failure, producing a result with a different error type. The success value is forwarded unchanged. Use this to translate or consolidate error unions at layer boundaries.

public static Result<TValue, TErrorOut> MapError<TValue, TErrorIn, TErrorOut>(this Result<TValue, TErrorIn> result, Func<TErrorIn, TErrorOut> mapper) where TErrorIn : IError where TErrorOut : IError

Parameters

result Result<TValue, TErrorIn>

The result whose error surface to translate.

mapper Func<TErrorIn, TErrorOut>

The function that converts the source error to the target error.

Returns

Result<TValue, TErrorOut>

A result with the mapped error type, or an Ok result with the original value when the input is a success.

Type Parameters

TValue

The success value type.

TErrorIn

The source error type.

TErrorOut

The target error type.

Examples

// Collapse a rich union into a single domain error at a layer boundary
Result<Order, ErrorsOf<ValidationError, InventoryError>> result = ...;

Result<Order, DomainError> translated = result.MapError(e => e.Match(
    v => new DomainError(v.Message),
    i => new DomainError(i.Message)));