From f99d035621971e5d3b3949a6d0c704083828a4d8 Mon Sep 17 00:00:00 2001
From: chylex <contact@chylex.com>
Date: Tue, 10 Apr 2018 19:45:41 +0200
Subject: [PATCH] Add a Result class that acts as an Either monad for a value
or exception
---
Data/Result.cs | 36 ++++++++++++++++++++++++++++++++++++
TweetDuck.csproj | 1 +
2 files changed, 37 insertions(+)
create mode 100644 Data/Result.cs
diff --git a/Data/Result.cs b/Data/Result.cs
new file mode 100644
index 00000000..2c582723
--- /dev/null
+++ b/Data/Result.cs
@@ -0,0 +1,36 @@
+using System;
+
+namespace TweetDuck.Data{
+ sealed class Result<T>{
+ public bool HasValue => exception == null;
+
+ public T Value => HasValue ? value : throw new InvalidOperationException("Requested value from a failed result.");
+ public Exception Exception => exception ?? throw new InvalidOperationException("Requested exception from a successful result.");
+
+ private readonly T value;
+ private readonly Exception exception;
+
+ public Result(T value){
+ this.value = value;
+ this.exception = null;
+ }
+
+ public Result(Exception exception){
+ this.value = default(T);
+ this.exception = exception ?? throw new ArgumentNullException(nameof(exception));
+ }
+
+ public void Handle(Action<T> onSuccess, Action<Exception> onException){
+ if (HasValue){
+ onSuccess(value);
+ }
+ else{
+ onException(exception);
+ }
+ }
+
+ public Result<R> Select<R>(Func<T, R> map){
+ return HasValue ? new Result<R>(map(value)) : new Result<R>(exception);
+ }
+ }
+}
diff --git a/TweetDuck.csproj b/TweetDuck.csproj
index 27df5cbd..fd09944d 100644
--- a/TweetDuck.csproj
+++ b/TweetDuck.csproj
@@ -259,6 +259,7 @@
</Compile>
<Compile Include="Core\Notification\Screenshot\TweetScreenshotManager.cs" />
<Compile Include="Data\ResourceLink.cs" />
+ <Compile Include="Data\Result.cs" />
<Compile Include="Data\Serialization\FileSerializer.cs" />
<Compile Include="Data\InjectedHTML.cs" />
<Compile Include="Data\Serialization\ITypeConverter.cs" />