support for dotnet9 compilation

Railway/Error.cs

@@ -221,15 +221,22 @@ public sealed class ExceptionalError : Error
     private static ImmutableDictionary<string, string> ExtractExtensionData(Exception exception)
     {
         if (!(exception.Data?.Count > 0))
-        return ImmutableDictionary<string, string>.Empty;
+            return ImmutableDictionary<string, string>.Empty;
 
+        var values = GetGenericExtData(exception);
+
+        return values is not null ? values.ToImmutable() : ImmutableDictionary<string, string>.Empty;
+    }
+
+    private static ImmutableDictionary<string, string>.Builder? GetGenericExtData(Exception ex)
+    {
         ImmutableDictionary<string, string>.Builder? values = null;
 
-        foreach (var key in exception.Data.Keys)
+        foreach (var key in ex.Data.Keys)
         {
             if (key is null) continue;
 
-            var value = exception.Data[key];
+            var value = ex.Data[key];
             if (value is null) continue;
 
             var keyString = key.ToString();
@@ -239,7 +246,8 @@ public sealed class ExceptionalError : Error
             values ??= ImmutableDictionary.CreateBuilder<string, string>();
             values.Add(keyString, valueString);
         }
-        return values is not null ? values.ToImmutable() : ImmutableDictionary<string, string>.Empty;
+
+        return values;
     }
 }
 

Railway/Railway.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFrameworks>net6.0;net7.0;net8.0</TargetFrameworks>
+    <TargetFrameworks>net6.0;net7.0;net8.0;net9.0</TargetFrameworks>
     <LangVersion>10.0</LangVersion>
     <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>enable</Nullable>

Railway/ResultExtensions.cs

@@ -5,7 +5,7 @@ namespace Just.Railway;
 public static partial class ResultExtensions
 {
     #region Match (with fallback)
-    
+
     public static T Match<T>(this in Result<T> result, Func<Error, T> fallback)
     {
         return result.State switch
@@ -15,7 +15,7 @@ public static partial class ResultExtensions
             _ => throw new ResultNotInitializedException(nameof(result))
         };
     }
-    
+
     public static async Task<T> Match<T>(this Result<T> result, Func<Error, Task<T>> fallback)
     {
         return result.State switch
@@ -77,7 +77,7 @@ public static partial class ResultExtensions
     }
 
     #endregion
-    
+
     #region Merge
 
     public static Result Merge(this IEnumerable<Result> results)