threadsafe-hint.md

ThreadSafe hint

Hints are used to fine-tune code generation. The ThreadSafe hint determines whether object composition will be created in a thread-safe manner. This hint is On by default. It is good practice not to use threads when creating an object graph, in which case this hint can be turned off, which will lead to a slight increase in performance. In addition, setup hints can be comments before the Setup method in the form hint = value, for example: // ThreadSafe = Off.

using Pure.DI;
using static Pure.DI.Hint;

DI.Setup(nameof(Composition))
    .Hint(ThreadSafe, "Off")
    .Bind().To<Dependency>()
    .Bind().As(Lifetime.Singleton).To<Service>()
    .Root<IService>("Root");

var composition = new Composition();
var service = composition.Root;

interface IDependency;

class Dependency : IDependency;

interface IService;

class Service(Func<IDependency> dependencyFactory) : IService;

Running this code sample locally

• Make sure you have the .NET SDK 9.0 or later is installed

dotnet --list-sdk

• Create a net9.0 (or later) console application

dotnet new console -n Sample

• Add reference to NuGet package
  • Pure.DI

dotnet add package Pure.DI

• Copy the example code into the Program.cs file

You are ready to run the example 🚀

dotnet run

For more hints, see this page.

The following partial class will be generated:

partial class Composition
{
  private readonly Composition _root;

  private Service? _singletonService44;

  [OrdinalAttribute(256)]
  public Composition()
  {
    _root = this;
  }

  internal Composition(Composition parentScope)
  {
    _root = (parentScope ?? throw new ArgumentNullException(nameof(parentScope)))._root;
  }

  public IService Root
  {
    [MethodImpl(MethodImplOptions.AggressiveInlining)]
    get
    {
      if (_root._singletonService44 is null)
      {
        Func<IDependency> perBlockFunc0 = new Func<IDependency>([MethodImpl(MethodImplOptions.AggressiveInlining)] () =>
        {
          IDependency localValue88 = new Dependency();
          return localValue88;
        });
        _root._singletonService44 = new Service(perBlockFunc0);
      }

      return _root._singletonService44;
    }
  }
}

Class diagram:

---
 config:
  class:
   hideEmptyMembersBox: true
---
classDiagram
	Service --|> IService
	Dependency --|> IDependency
	Composition ..> Service : IService Root
	Service o-- "PerBlock" FuncᐸIDependencyᐳ : FuncᐸIDependencyᐳ
	FuncᐸIDependencyᐳ *--  Dependency : IDependency
	namespace Pure.DI.UsageTests.Hints.ThreadSafeHintScenario {
		class Composition {
		<<partial>>
		+IService Root
		}
		class Dependency {
			+Dependency()
		}
		class IDependency {
			<<interface>>
		}
		class IService {
			<<interface>>
		}
		class Service {
			+Service(FuncᐸIDependencyᐳ dependencyFactory)
		}
	}
	namespace System {
		class FuncᐸIDependencyᐳ {
				<<delegate>>
		}
	}

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