request/src/request.result/Result.Transform.cs
Louis Seubert cb2628c615 feat: add none generic result type
This adds a none generic result type and refactors the result to be a
class. The Result has the same inheritance like `Task` and `Task<T>`
2026-05-26 19:21:29 +02:00

1059 lines
35 KiB
C#

// Copyright (c) The Geekeey Authors
// SPDX-License-Identifier: EUPL-1.2
using System.Diagnostics.Contracts;
namespace Geekeey.Request.Result;
public partial class Result<T>
{
/// <summary>
/// Maps the success value of the result using a mapping function, or does nothing if the result is a failure.
/// </summary>
/// <param name="func">The function used to map the success value.</param>
/// <typeparam name="TNew">The type of the new value.</typeparam>
/// <returns>A new result containing either the mapped success value or the failure value of the original
/// result.</returns>
[Pure]
public Result<TNew> Map<TNew>(Func<T, TNew> func)
{
return IsSuccess ? new Result<TNew>(func(Value)) : new Result<TNew>(Error);
}
/// <summary>
/// Tries to map the success value of the result using a mapping function, or does nothing if the result is a
/// failure. If the mapping function throws an exception, the exception will be returned wrapped in an
/// <see cref="ExceptionError"/>.
/// </summary>
/// <param name="func">The function used to map the success value.</param>
/// <typeparam name="TNew">The type of the new value.</typeparam>
/// <returns>A new result containing either the mapped value, the exception thrown by <paramref name="func"/>
/// wrapped in an <see cref="ExceptionError"/>, or the failure value of the original result.</returns>
[Pure]
public Result<TNew> TryMap<TNew>(Func<T, TNew> func)
{
try
{
return Map(func);
}
catch (Exception exception)
{
return new Result<TNew>(new ExceptionError(exception));
}
}
/// <summary>
/// Maps the success value of the result to a new result using a mapping function, or does nothing if the result is
/// a failure.
/// </summary>
/// <param name="func">The function used to map the success value to a new result.</param>
/// <typeparam name="TNew">The type of the new value.</typeparam>
/// <returns>A result which is either the mapped result or a new result containing the failure value of the original
/// result.</returns>
[Pure]
public Result<TNew> Then<TNew>(Func<T, Result<TNew>> func)
{
return IsSuccess ? func(Value) : new Result<TNew>(Error);
}
/// <summary>
/// Tries to map the success value of the result to a new result using a mapping function, or does nothing if the result
/// is a failure. If the mapping function throws an exception, the exception will be returned wrapped in an
/// <see cref="ExceptionError"/>.
/// </summary>
/// <param name="func">The function used to map the success value to a new result.</param>
/// <typeparam name="TNew">The type of the new value.</typeparam>
/// <returns>A result which is either the mapped result, the exception thrown by <paramref name="func"/> wrapped in
/// an <see cref="ExceptionError"/>, or a new result containing the failure value of the original result.</returns>
[Pure]
public Result<TNew> ThenTry<TNew>(Func<T, Result<TNew>> func)
{
try
{
return Then(func);
}
catch (Exception exception)
{
return new Result<TNew>(new ExceptionError(exception));
}
}
}
public partial class Result<T>
{
/// <summary>
/// Maps the success value of the result using an asynchronous mapping function, or does nothing if the result is
/// a failure.
/// </summary>
/// <param name="func">The function used to map the success value.</param>
/// <typeparam name="TNew">The type of the new value.</typeparam>
/// <returns>A <see cref="Task{T}"/> which either completes asynchronously by invoking the mapping function on
/// the success value of the result and constructing a new result containing the mapped value, or completes
/// synchronously by returning a new result containing the failure value of the original result.</returns>
[Pure]
public Task<Result<TNew>> MapAsync<TNew>(Func<T, Task<TNew>> func)
{
if (!IsSuccess)
{
return Task.FromResult(new Result<TNew>(Error));
}
var task = func(Value);
return CreateResult(task);
static async Task<Result<TNew>> CreateResult(Task<TNew> task)
{
var value = await task;
return new Result<TNew>(value);
}
}
/// <summary>
/// Maps the success value of the result using an asynchronous mapping function, or does nothing if the result is a
/// failure. If the mapping function throws an exception, the exception will be returned wrapped in an
/// <see cref="ExceptionError"/>.
/// </summary>
/// <param name="func">The function used to map the success value.</param>
/// <typeparam name="TNew">The type of the new value.</typeparam>
/// <returns>A <see cref="Task{T}"/> which either completes asynchronously by invoking the mapping function on
/// the success value of the result and constructing a new result containing the mapped value, returning any exception
/// thrown by <paramref name="func"/> wrapped in an <see cref="ExceptionError"/> or completes synchronously by
/// returning a new result containing the failure value of the original result.</returns>
[Pure]
public Task<Result<TNew>> TryMapAsync<TNew>(Func<T, Task<TNew>> func)
{
if (!IsSuccess)
{
return Task.FromResult(new Result<TNew>(Error));
}
try
{
var task = func(Value);
return CreateResult(task);
}
catch (Exception exception)
{
return Task.FromResult(new Result<TNew>(new ExceptionError(exception)));
}
static async Task<Result<TNew>> CreateResult(Task<TNew> task)
{
try
{
var value = await task;
return new Result<TNew>(value);
}
catch (Exception exception)
{
return new Result<TNew>(new ExceptionError(exception));
}
}
}
/// <summary>
/// Maps the success value of the result to a new result using an asynchronous mapping function, or does nothing if
/// the result is a failure.
/// </summary>
/// <param name="func">The function used to map the success value to a new result.</param>
/// <typeparam name="TNew">The type of the new value.</typeparam>
/// <returns>A <see cref="Task{T}"/> which either completes asynchronously by invoking the mapping function on
/// the success value of the result, or completes synchronously by returning a new result containing the failure
/// value of the original result.</returns>
[Pure]
public Task<Result<TNew>> ThenAsync<TNew>(Func<T, Task<Result<TNew>>> func)
{
if (!IsSuccess)
{
return Task.FromResult(new Result<TNew>(Error));
}
var task = func(Value);
return CreateResult(task);
static async Task<Result<TNew>> CreateResult(Task<Result<TNew>> task)
{
var result = await task;
return result;
}
}
/// <summary>
/// Maps the success value of the result to a new result using an asynchronous mapping function, or does nothing if
/// the result is a failure. If the mapping function throws an exception, the exception will be returned wrapped in
/// an <see cref="ExceptionError"/>.
/// </summary>
/// <param name="func">The function used to map the success value to a new result.</param>
/// <typeparam name="TNew">The type of the new value.</typeparam>
/// <returns>A <see cref="Task{T}"/> which either completes asynchronously by invoking the mapping function on
/// the success value of the result, returning any exception thrown by <paramref name="func"/> wrapped in an
/// <see cref="ExceptionError"/>, or completes synchronously by returning a new result containing the failure value
/// of the original result.</returns>
[Pure]
public Task<Result<TNew>> ThenTryAsync<TNew>(Func<T, Task<Result<TNew>>> func)
{
if (!IsSuccess)
{
return Task.FromResult(new Result<TNew>(Error));
}
try
{
var task = func(Value);
return CreateResult(task);
}
catch (Exception exception)
{
return Task.FromResult(new Result<TNew>(new ExceptionError(exception)));
}
static async Task<Result<TNew>> CreateResult(Task<Result<TNew>> task)
{
try
{
var value = await task;
return value;
}
catch (Exception exception)
{
return new Result<TNew>(new ExceptionError(exception));
}
}
}
}
public partial class Result<T>
{
/// <summary>
/// Maps the success value of the result using an asynchronous mapping function, or does nothing if the result is
/// a failure.
/// </summary>
/// <param name="func">The function used to map the success value.</param>
/// <typeparam name="TNew">The type of the new value.</typeparam>
/// <returns>A <see cref="ValueTask{T}"/> which either completes asynchronously by invoking the mapping function on
/// the success value of the result and constructing a new result containing the mapped value, or completes
/// synchronously by returning a new result containing the failure value of the original result.</returns>
[Pure]
public ValueTask<Result<TNew>> MapAsync<TNew>(Func<T, ValueTask<TNew>> func)
{
if (!IsSuccess)
{
return ValueTask.FromResult(new Result<TNew>(Error));
}
var task = func(Value);
return CreateResult(task);
static async ValueTask<Result<TNew>> CreateResult(ValueTask<TNew> task)
{
var value = await task;
return new Result<TNew>(value);
}
}
/// <summary>
/// Maps the success value of the result using an asynchronous mapping function, or does nothing if the result is a
/// failure. If the mapping function throws an exception, the exception will be returned wrapped in an
/// <see cref="ExceptionError"/>.
/// </summary>
/// <param name="func">The function used to map the success value.</param>
/// <typeparam name="TNew">The type of the new value.</typeparam>
/// <returns>A <see cref="ValueTask{T}"/> which either completes asynchronously by invoking the mapping function on
/// the success value of the result and constructing a new result containing the mapped value, returning any exception
/// thrown by <paramref name="func"/> wrapped in an <see cref="ExceptionError"/> or completes synchronously by
/// returning a new result containing the failure value of the original result.</returns>
[Pure]
public ValueTask<Result<TNew>> TryMapAsync<TNew>(Func<T, ValueTask<TNew>> func)
{
if (!IsSuccess)
{
return ValueTask.FromResult(new Result<TNew>(Error));
}
try
{
var task = func(Value);
return CreateResult(task);
}
catch (Exception exception)
{
return ValueTask.FromResult(new Result<TNew>(new ExceptionError(exception)));
}
static async ValueTask<Result<TNew>> CreateResult(ValueTask<TNew> task)
{
try
{
var value = await task;
return new Result<TNew>(value);
}
catch (Exception exception)
{
return new Result<TNew>(new ExceptionError(exception));
}
}
}
/// <summary>
/// Maps the success value of the result to a new result using an asynchronous mapping function, or does nothing if
/// the result is a failure.
/// </summary>
/// <param name="func">The function used to map the success value to a new result.</param>
/// <typeparam name="TNew">The type of the new value.</typeparam>
/// <returns>A <see cref="ValueTask{T}"/> which either completes asynchronously by invoking the mapping function on
/// the success value of the result, or completes synchronously by returning a new result containing the failure
/// value of the original result.</returns>
[Pure]
public ValueTask<Result<TNew>> ThenAsync<TNew>(Func<T, ValueTask<Result<TNew>>> func)
{
if (!IsSuccess)
{
return ValueTask.FromResult(new Result<TNew>(Error));
}
var task = func(Value);
return CreateResult(task);
static async ValueTask<Result<TNew>> CreateResult(ValueTask<Result<TNew>> task)
{
var result = await task;
return result;
}
}
/// <summary>
/// Maps the success value of the result to a new result using an asynchronous mapping function, or does nothing if
/// the result is a failure. If the mapping function throws an exception, the exception will be returned wrapped in
/// an <see cref="ExceptionError"/>.
/// </summary>
/// <param name="func">The function used to map the success value to a new result.</param>
/// <typeparam name="TNew">The type of the new value.</typeparam>
/// <returns>A <see cref="ValueTask{T}"/> which either completes asynchronously by invoking the mapping function on
/// the success value of the result, returning any exception thrown by <paramref name="func"/> wrapped in an
/// <see cref="ExceptionError"/>, or completes synchronously by returning a new result containing the failure value
/// of the original result.</returns>
[Pure]
public ValueTask<Result<TNew>> ThenTryAsync<TNew>(Func<T, ValueTask<Result<TNew>>> func)
{
if (!IsSuccess)
{
return ValueTask.FromResult(new Result<TNew>(Error));
}
try
{
var task = func(Value);
return CreateResult(task);
}
catch (Exception exception)
{
return ValueTask.FromResult(new Result<TNew>(new ExceptionError(exception)));
}
static async ValueTask<Result<TNew>> CreateResult(ValueTask<Result<TNew>> task)
{
try
{
var value = await task;
return value;
}
catch (Exception exception)
{
return new Result<TNew>(new ExceptionError(exception));
}
}
}
}
public partial class Result<T>
{
/// <summary>
/// Chains a non-generic result to this result if it is a success, or does nothing if the result is a failure.
/// </summary>
/// <param name="func">The function used to create the next result.</param>
/// <returns>A result which is either the mapped result or a new result containing the failure value of the original
/// result.</returns>
[Pure]
public Result Then(Func<T, Result> func)
{
return IsSuccess ? func(Value) : new Result(Error);
}
/// <summary>
/// Tries to chain a non-generic result to this result if it is a success, or does nothing if the result is a
/// failure. If the function throws an exception, the exception will be returned wrapped in an
/// <see cref="ExceptionError"/>.
/// </summary>
/// <param name="func">The function used to create the next result.</param>
/// <returns>A result which is either the mapped result, the exception thrown by <paramref name="func"/> wrapped in
/// an <see cref="ExceptionError"/>, or a new result containing the failure value of the original result.</returns>
[Pure]
public Result ThenTry(Func<T, Result> func)
{
try
{
return Then(func);
}
catch (Exception exception)
{
return new Result(new ExceptionError(exception));
}
}
}
public partial class Result<T>
{
/// <summary>
/// Chains a non-generic result to this result using an asynchronous mapping function, or does nothing if the result is
/// a failure.
/// </summary>
/// <param name="func">The function used to create the next result.</param>
/// <returns>A <see cref="Task{T}"/> which either completes asynchronously by invoking the mapping function, or
/// completes synchronously by returning a new result containing the failure value of the original result.</returns>
[Pure]
public Task<Result> ThenAsync(Func<T, Task<Result>> func)
{
if (!IsSuccess)
{
return Task.FromResult(new Result(Error));
}
var task = func(Value);
return CreateResult(task);
static async Task<Result> CreateResult(Task<Result> task)
{
var result = await task;
return result;
}
}
/// <summary>
/// Tries to chain a non-generic result to this result using an asynchronous mapping function, or does nothing if the
/// result is a failure. If the mapping function throws an exception, the exception will be returned wrapped in
/// an <see cref="ExceptionError"/>.
/// </summary>
/// <param name="func">The function used to create the next result.</param>
/// <returns>A <see cref="Task{T}"/> which either completes asynchronously by invoking the mapping function,
/// returning any exception thrown by <paramref name="func"/> wrapped in an <see cref="ExceptionError"/>, or
/// completes synchronously by returning a new result containing the failure value of the original result.</returns>
[Pure]
public Task<Result> ThenTryAsync(Func<T, Task<Result>> func)
{
if (!IsSuccess)
{
return Task.FromResult(new Result(Error));
}
try
{
var task = func(Value);
return CreateResult(task);
}
catch (Exception exception)
{
return Task.FromResult(new Result(new ExceptionError(exception)));
}
static async Task<Result> CreateResult(Task<Result> task)
{
try
{
var value = await task;
return value;
}
catch (Exception exception)
{
return new Result(new ExceptionError(exception));
}
}
}
}
public partial class Result<T>
{
/// <summary>
/// Chains a non-generic result to this result using an asynchronous mapping function, or does nothing if the result is
/// a failure.
/// </summary>
/// <param name="func">The function used to create the next result.</param>
/// <returns>A <see cref="ValueTask{T}"/> which either completes asynchronously by invoking the mapping function, or
/// completes synchronously by returning a new result containing the failure value of the original result.</returns>
[Pure]
public ValueTask<Result> ThenAsync(Func<T, ValueTask<Result>> func)
{
if (!IsSuccess)
{
return ValueTask.FromResult(new Result(Error));
}
var task = func(Value);
return CreateResult(task);
static async ValueTask<Result> CreateResult(ValueTask<Result> task)
{
var result = await task;
return result;
}
}
/// <summary>
/// Tries to chain a non-generic result to this result using an asynchronous mapping function, or does nothing if the
/// result is a failure. If the mapping function throws an exception, the exception will be returned wrapped in
/// an <see cref="ExceptionError"/>.
/// </summary>
/// <param name="func">The function used to create the next result.</param>
/// <returns>A <see cref="ValueTask{T}"/> which either completes asynchronously by invoking the mapping function,
/// returning any exception thrown by <paramref name="func"/> wrapped in an <see cref="ExceptionError"/>, or
/// completes synchronously by returning a new result containing the failure value of the original result.</returns>
[Pure]
public ValueTask<Result> ThenTryAsync(Func<T, ValueTask<Result>> func)
{
if (!IsSuccess)
{
return ValueTask.FromResult(new Result(Error));
}
try
{
var task = func(Value);
return CreateResult(task);
}
catch (Exception exception)
{
return ValueTask.FromResult(new Result(new ExceptionError(exception)));
}
static async ValueTask<Result> CreateResult(ValueTask<Result> task)
{
try
{
var value = await task;
return value;
}
catch (Exception exception)
{
return new Result(new ExceptionError(exception));
}
}
}
}
public partial class Result
{
/// <summary>
/// Maps the success of the result to a new success value using a mapping function, or does nothing if the result is
/// a failure.
/// </summary>
/// <param name="func">The function used to map the success to a new value.</param>
/// <typeparam name="TNew">The type of the new value.</typeparam>
/// <returns>A new result containing either the mapped success value or the failure value of the original
/// result.</returns>
[Pure]
public Result<TNew> Map<TNew>(Func<TNew> func)
{
return IsSuccess ? new Result<TNew>(func()) : new Result<TNew>(Error);
}
/// <summary>
/// Tries to map the success of the result to a new success value using a mapping function, or does nothing if the
/// result is a failure. If the mapping function throws an exception, the exception will be returned wrapped in an
/// <see cref="ExceptionError"/>.
/// </summary>
/// <param name="func">The function used to map the success to a new value.</param>
/// <typeparam name="TNew">The type of the new value.</typeparam>
/// <returns>A new result containing either the mapped value, the exception thrown by <paramref name="func"/>
/// wrapped in an <see cref="ExceptionError"/>, or the failure value of the original result.</returns>
[Pure]
public Result<TNew> TryMap<TNew>(Func<TNew> func)
{
try
{
return Map(func);
}
catch (Exception exception)
{
return new Result<TNew>(new ExceptionError(exception));
}
}
/// <summary>
/// Chains another result to this result if it is a success, or does nothing if the result is a failure.
/// </summary>
/// <param name="func">The function used to create the next result.</param>
/// <returns>A result which is either the mapped result or a new result containing the failure value of the original
/// result.</returns>
[Pure]
public Result Then(Func<Result> func)
{
return IsSuccess ? func() : new Result(Error);
}
/// <summary>
/// Tries to chain another result to this result if it is a success, or does nothing if the result is a failure. If
/// the function throws an exception, the exception will be returned wrapped in an <see cref="ExceptionError"/>.
/// </summary>
/// <param name="func">The function used to create the next result.</param>
/// <returns>A result which is either the mapped result, the exception thrown by <paramref name="func"/> wrapped in
/// an <see cref="ExceptionError"/>, or a new result containing the failure value of the original result.</returns>
[Pure]
public Result ThenTry(Func<Result> func)
{
try
{
return Then(func);
}
catch (Exception exception)
{
return new Result(new ExceptionError(exception));
}
}
/// <summary>
/// Chains a generic result to this result if it is a success, or does nothing if the result is a failure.
/// </summary>
/// <param name="func">The function used to create the next generic result.</param>
/// <typeparam name="TNew">The type of the new value.</typeparam>
/// <returns>A result which is either the mapped result or a new result containing the failure value of the original
/// result.</returns>
[Pure]
public Result<TNew> Then<TNew>(Func<Result<TNew>> func)
{
return IsSuccess ? func() : new Result<TNew>(Error);
}
/// <summary>
/// Tries to chain a generic result to this result if it is a success, or does nothing if the result is a failure. If
/// the function throws an exception, the exception will be returned wrapped in an <see cref="ExceptionError"/>.
/// </summary>
/// <param name="func">The function used to create the next generic result.</param>
/// <typeparam name="TNew">The type of the new value.</typeparam>
/// <returns>A result which is either the mapped result, the exception thrown by <paramref name="func"/> wrapped in
/// an <see cref="ExceptionError"/>, or a new result containing the failure value of the original result.</returns>
[Pure]
public Result<TNew> ThenTry<TNew>(Func<Result<TNew>> func)
{
try
{
return Then(func);
}
catch (Exception exception)
{
return new Result<TNew>(new ExceptionError(exception));
}
}
}
public partial class Result
{
/// <summary>
/// Maps the success of the result using an asynchronous mapping function, or does nothing if the result is
/// a failure.
/// </summary>
/// <param name="func">The function used to map the success.</param>
/// <typeparam name="TNew">The type of the new value.</typeparam>
/// <returns>A <see cref="Task{T}"/> which either completes asynchronously by invoking the mapping function and
/// constructing a new result containing the mapped value, or completes synchronously by returning a new result
/// containing the failure value of the original result.</returns>
[Pure]
public Task<Result<TNew>> MapAsync<TNew>(Func<Task<TNew>> func)
{
if (!IsSuccess)
{
return Task.FromResult(new Result<TNew>(Error));
}
var task = func();
return CreateResult(task);
static async Task<Result<TNew>> CreateResult(Task<TNew> task)
{
var value = await task;
return new Result<TNew>(value);
}
}
/// <summary>
/// Maps the success of the result using an asynchronous mapping function, or does nothing if the result is a
/// failure. If the mapping function throws an exception, the exception will be returned wrapped in an
/// <see cref="ExceptionError"/>.
/// </summary>
/// <param name="func">The function used to map the success.</param>
/// <typeparam name="TNew">The type of the new value.</typeparam>
/// <returns>A <see cref="Task{T}"/> which either completes asynchronously by invoking the mapping function and
/// constructing a new result containing the mapped value, returning any exception thrown by <paramref name="func"/>
/// wrapped in an <see cref="ExceptionError"/> or completes synchronously by returning a new result containing the
/// failure value of the original result.</returns>
[Pure]
public Task<Result<TNew>> TryMapAsync<TNew>(Func<Task<TNew>> func)
{
if (!IsSuccess)
{
return Task.FromResult(new Result<TNew>(Error));
}
try
{
var task = func();
return CreateResult(task);
}
catch (Exception exception)
{
return Task.FromResult(new Result<TNew>(new ExceptionError(exception)));
}
static async Task<Result<TNew>> CreateResult(Task<TNew> task)
{
try
{
var value = await task;
return new Result<TNew>(value);
}
catch (Exception exception)
{
return new Result<TNew>(new ExceptionError(exception));
}
}
}
/// <summary>
/// Chains another result to this result using an asynchronous mapping function, or does nothing if the result is
/// a failure.
/// </summary>
/// <param name="func">The function used to create the next result.</param>
/// <returns>A <see cref="Task{T}"/> which either completes asynchronously by invoking the mapping function, or
/// completes synchronously by returning a new result containing the failure value of the original result.</returns>
[Pure]
public Task<Result> ThenAsync(Func<Task<Result>> func)
{
if (!IsSuccess)
{
return Task.FromResult(new Result(Error));
}
var task = func();
return CreateResult(task);
static async Task<Result> CreateResult(Task<Result> task)
{
var result = await task;
return result;
}
}
/// <summary>
/// Tries to chain another result to this result using an asynchronous mapping function, or does nothing if the
/// result is a failure. If the mapping function throws an exception, the exception will be returned wrapped in
/// an <see cref="ExceptionError"/>.
/// </summary>
/// <param name="func">The function used to create the next result.</param>
/// <returns>A <see cref="Task{T}"/> which either completes asynchronously by invoking the mapping function,
/// returning any exception thrown by <paramref name="func"/> wrapped in an <see cref="ExceptionError"/>, or
/// completes synchronously by returning a new result containing the failure value of the original result.</returns>
[Pure]
public Task<Result> ThenTryAsync(Func<Task<Result>> func)
{
if (!IsSuccess)
{
return Task.FromResult(new Result(Error));
}
try
{
var task = func();
return CreateResult(task);
}
catch (Exception exception)
{
return Task.FromResult(new Result(new ExceptionError(exception)));
}
static async Task<Result> CreateResult(Task<Result> task)
{
try
{
var value = await task;
return value;
}
catch (Exception exception)
{
return new Result(new ExceptionError(exception));
}
}
}
/// <summary>
/// Chains a generic result to this result using an asynchronous mapping function, or does nothing if the result is
/// a failure.
/// </summary>
/// <param name="func">The function used to create the next result.</param>
/// <typeparam name="TNew">The type of the new value.</typeparam>
/// <returns>A <see cref="Task{T}"/> which either completes asynchronously by invoking the mapping function, or
/// completes synchronously by returning a new result containing the failure value of the original result.</returns>
[Pure]
public Task<Result<TNew>> ThenAsync<TNew>(Func<Task<Result<TNew>>> func)
{
if (!IsSuccess)
{
return Task.FromResult(new Result<TNew>(Error));
}
var task = func();
return CreateResult(task);
static async Task<Result<TNew>> CreateResult(Task<Result<TNew>> task)
{
var result = await task;
return result;
}
}
/// <summary>
/// Tries to chain a generic result to this result using an asynchronous mapping function, or does nothing if the
/// result is a failure. If the mapping function throws an exception, the exception will be returned wrapped in
/// an <see cref="ExceptionError"/>.
/// </summary>
/// <param name="func">The function used to create the next result.</param>
/// <typeparam name="TNew">The type of the new value.</typeparam>
/// <returns>A <see cref="Task{T}"/> which either completes asynchronously by invoking the mapping function,
/// returning any exception thrown by <paramref name="func"/> wrapped in an <see cref="ExceptionError"/>, or
/// completes synchronously by returning a new result containing the failure value of the original result.</returns>
[Pure]
public Task<Result<TNew>> ThenTryAsync<TNew>(Func<Task<Result<TNew>>> func)
{
if (!IsSuccess)
{
return Task.FromResult(new Result<TNew>(Error));
}
try
{
var task = func();
return CreateResult(task);
}
catch (Exception exception)
{
return Task.FromResult(new Result<TNew>(new ExceptionError(exception)));
}
static async Task<Result<TNew>> CreateResult(Task<Result<TNew>> task)
{
try
{
var value = await task;
return value;
}
catch (Exception exception)
{
return new Result<TNew>(new ExceptionError(exception));
}
}
}
}
public partial class Result
{
/// <summary>
/// Maps the success of the result using an asynchronous mapping function, or does nothing if the result is
/// a failure.
/// </summary>
/// <param name="func">The function used to map the success.</param>
/// <typeparam name="TNew">The type of the new value.</typeparam>
/// <returns>A <see cref="ValueTask{T}"/> which either completes asynchronously by invoking the mapping function and
/// constructing a new result containing the mapped value, or completes synchronously by returning a new result
/// containing the failure value of the original result.</returns>
[Pure]
public ValueTask<Result<TNew>> MapAsync<TNew>(Func<ValueTask<TNew>> func)
{
if (!IsSuccess)
{
return ValueTask.FromResult(new Result<TNew>(Error));
}
var task = func();
return CreateResult(task);
static async ValueTask<Result<TNew>> CreateResult(ValueTask<TNew> task)
{
var value = await task;
return new Result<TNew>(value);
}
}
/// <summary>
/// Maps the success of the result using an asynchronous mapping function, or does nothing if the result is a
/// failure. If the mapping function throws an exception, the exception will be returned wrapped in an
/// <see cref="ExceptionError"/>.
/// </summary>
/// <param name="func">The function used to map the success.</param>
/// <typeparam name="TNew">The type of the new value.</typeparam>
/// <returns>A <see cref="ValueTask{T}"/> which either completes asynchronously by invoking the mapping function and
/// constructing a new result containing the mapped value, returning any exception thrown by <paramref name="func"/>
/// wrapped in an <see cref="ExceptionError"/> or completes synchronously by returning a new result containing the
/// failure value of the original result.</returns>
[Pure]
public ValueTask<Result<TNew>> TryMapAsync<TNew>(Func<ValueTask<TNew>> func)
{
if (!IsSuccess)
{
return ValueTask.FromResult(new Result<TNew>(Error));
}
try
{
var task = func();
return CreateResult(task);
}
catch (Exception exception)
{
return ValueTask.FromResult(new Result<TNew>(new ExceptionError(exception)));
}
static async ValueTask<Result<TNew>> CreateResult(ValueTask<TNew> task)
{
try
{
var value = await task;
return new Result<TNew>(value);
}
catch (Exception exception)
{
return new Result<TNew>(new ExceptionError(exception));
}
}
}
/// <summary>
/// Chains another result to this result using an asynchronous mapping function, or does nothing if the result is
/// a failure.
/// </summary>
/// <param name="func">The function used to create the next result.</param>
/// <returns>A <see cref="ValueTask{T}"/> which either completes asynchronously by invoking the mapping function, or
/// completes synchronously by returning a new result containing the failure value of the original result.</returns>
[Pure]
public ValueTask<Result> ThenAsync(Func<ValueTask<Result>> func)
{
if (!IsSuccess)
{
return ValueTask.FromResult(new Result(Error));
}
var task = func();
return CreateResult(task);
static async ValueTask<Result> CreateResult(ValueTask<Result> task)
{
var result = await task;
return result;
}
}
/// <summary>
/// Tries to chain another result to this result using an asynchronous mapping function, or does nothing if the
/// result is a failure. If the mapping function throws an exception, the exception will be returned wrapped in
/// an <see cref="ExceptionError"/>.
/// </summary>
/// <param name="func">The function used to create the next result.</param>
/// <returns>A <see cref="ValueTask{T}"/> which either completes asynchronously by invoking the mapping function,
/// returning any exception thrown by <paramref name="func"/> wrapped in an <see cref="ExceptionError"/>, or
/// completes synchronously by returning a new result containing the failure value of the original result.</returns>
[Pure]
public ValueTask<Result> ThenTryAsync(Func<ValueTask<Result>> func)
{
if (!IsSuccess)
{
return ValueTask.FromResult(new Result(Error));
}
try
{
var task = func();
return CreateResult(task);
}
catch (Exception exception)
{
return ValueTask.FromResult(new Result(new ExceptionError(exception)));
}
static async ValueTask<Result> CreateResult(ValueTask<Result> task)
{
try
{
var value = await task;
return value;
}
catch (Exception exception)
{
return new Result(new ExceptionError(exception));
}
}
}
/// <summary>
/// Chains a generic result to this result using an asynchronous mapping function, or does nothing if the result is
/// a failure.
/// </summary>
/// <param name="func">The function used to create the next result.</param>
/// <typeparam name="TNew">The type of the new value.</typeparam>
/// <returns>A <see cref="ValueTask{T}"/> which either completes asynchronously by invoking the mapping function, or
/// completes synchronously by returning a new result containing the failure value of the original result.</returns>
[Pure]
public ValueTask<Result<TNew>> ThenAsync<TNew>(Func<ValueTask<Result<TNew>>> func)
{
if (!IsSuccess)
{
return ValueTask.FromResult(new Result<TNew>(Error));
}
var task = func();
return CreateResult(task);
static async ValueTask<Result<TNew>> CreateResult(ValueTask<Result<TNew>> task)
{
var result = await task;
return result;
}
}
/// <summary>
/// Tries to chain a generic result to this result using an asynchronous mapping function, or does nothing if the
/// result is a failure. If the mapping function throws an exception, the exception will be returned wrapped in
/// an <see cref="ExceptionError"/>.
/// </summary>
/// <param name="func">The function used to create the next result.</param>
/// <typeparam name="TNew">The type of the new value.</typeparam>
/// <returns>A <see cref="ValueTask{T}"/> which either completes asynchronously by invoking the mapping function,
/// returning any exception thrown by <paramref name="func"/> wrapped in an <see cref="ExceptionError"/>, or
/// completes synchronously by returning a new result containing the failure value of the original result.</returns>
[Pure]
public ValueTask<Result<TNew>> ThenTryAsync<TNew>(Func<ValueTask<Result<TNew>>> func)
{
if (!IsSuccess)
{
return ValueTask.FromResult(new Result<TNew>(Error));
}
try
{
var task = func();
return CreateResult(task);
}
catch (Exception exception)
{
return ValueTask.FromResult(new Result<TNew>(new ExceptionError(exception)));
}
static async ValueTask<Result<TNew>> CreateResult(ValueTask<Result<TNew>> task)
{
try
{
var value = await task;
return value;
}
catch (Exception exception)
{
return new Result<TNew>(new ExceptionError(exception));
}
}
}
}