FastGenericNew

The ultimate fast and powerful alternative to Activator.CreateInstance<T> / new T()

✨ Features

• ✔️ The best CreateInstance ever

  • Up to 50x faster than Activator.CreateInstance<T>
  • Generic Parameters Support
  • Zero boxing/unboxing
  • TryGetValue-like TryFastNew API
  • Link Mode PublishTrimmed Support
  • Non-Public Constructor Support
  • No Generic Constraints
  • Compatible with .NET Standard 2.0
  • Multiple backend implementations
  • Heavily tested on Win/Mac/Linux

• 🪛 Modern Compiler Integration

  • Source Generator v2 (Incremental Generator)
  • Highly Configurable (Props)
  • Multi-threaded Generation

• 🔥 Latest C#/.NET Features Support

  • C# 8 Nullable Support
  • C# 10 Parameterless struct constructors Support (Both invokes or not)
  • WebAssembly Support

🔧 Installation

You should only use one of them

Pre-Compiled Version

dotnet add package FastGenericNew --version 3.3.0 <ItemGroup> <PackageReference Include="FastGenericNew" Version="3.3.0" /> </ItemGroup>

SourceGenerator Version

dotnet add package FastGenericNew.SourceGenerator --version 3.3.0 <ItemGroup> <PackageReference Include="FastGenericNew.SourceGenerator" Version="3.3.0" /> </ItemGroup>

SourceGeneratorV2 requires

.NET Standard 2.0 or above
C# 8.0 or above
Roslyn 4.0.1 or above
Modern IDE (Optional) [VS2022, Rider, VSCode]

📖 Examples

using FastGenericNew; // Simply replace 'Activator' to 'FastNew' var obj = FastNew.CreateInstance<T>(); // With parameter(s) var obj2 = FastNew.CreateInstance<T, string>("text"); var obj3 = FastNew.CreateInstance<T, string, int>("text", 0); // Try pattern // NOTE: The try pattern will only check if the constructor can be called. // It will not catch or handle any exceptions thrown in the constructor. if (FastNew.TryCreateInstance<T, string>("arg0", out T result)); { // ... }

Notes

With .NET Framework, Activator.CreateInstance<T>() invokes the parameterless constructor of ValueType if
the constraint is where T : new() but appears to ignore the parameterless constructor if the constraint is where T : struct.
But FastNew.CreateInstance<T>() will always invoke the parameterless constructor if it's available.

If you don't want to invoke the parameterless constructor of ValueType, consider using FastNew.NewOrDefault<T>() which will never invoke the parameterless constructor of ValueType

🚀 Benchmark

Environment

BenchmarkDotNet=v0.13.1, OS=Windows 10.0.22000 AMD Ryzen 9 3900X, 1 CPU, 24 logical and 12 physical cores .NET SDK=6.0.200-preview.22055.15 [Host] : .NET 6.0.2 (6.0.222.6406), X64 RyuJIT .NET 5.0 : .NET 5.0.14 (5.0.1422.5710), X64 RyuJIT .NET 6.0 : .NET 6.0.2 (6.0.222.6406), X64 RyuJIT .NET Framework 4.8 : .NET Framework 4.8 (4.8.4470.0), X64 RyuJIT

Reference Types

Value Types

📜 License

FastGenericNew is licensed under the MIT license.