C#•2y ago

✅ why dispose call is the latest in the chain?

Actually I have two questions here:

How actually duck typing works? Why I can do this:

using var refStruct = new RefStruct();
public ref struct RefStruct
{
 public void Dispose()
 {
     Console.WriteLine("Hello from ref struct!");
 }
}

using var refStruct = new RefStruct();
public ref struct RefStruct
{
 public void Dispose()
 {
     Console.WriteLine("Hello from ref struct!");
 }
}

using var refStruct = new RefStruct();
public ref struct RefStruct
{
 public void Dispose()
 {
     Console.WriteLine("Hello from ref struct!");
 }
}

using var refStruct = new RefStruct();
public ref struct RefStruct
{
 public void Dispose()
 {
     Console.WriteLine("Hello from ref struct!");
 }
}

but can't do the same with class, class requires to inherit

IDisposable

IDisposable

IDisposable

IDisposable and it is strange:

using var simpleClass = new SimpleClass();
public class SimpleClass
{
 public void Dispose()
 {
     Console.WriteLine("Hello from class!");
 }
}

using var simpleClass = new SimpleClass();
public class SimpleClass
{
 public void Dispose()
 {
     Console.WriteLine("Hello from class!");
 }
}

using var simpleClass = new SimpleClass();
public class SimpleClass
{
 public void Dispose()
 {
     Console.WriteLine("Hello from class!");
 }
}

using var simpleClass = new SimpleClass();
public class SimpleClass
{
 public void Dispose()
 {
     Console.WriteLine("Hello from class!");
 }
}

2 question is: why dispose call is the latest in the chain? for example:

using var refStruct = new RefStruct();
using var simpleClass = new SimpleClass();
var factory = Factory.Create();
Console.WriteLine(factory);

using var refStruct = new RefStruct();
using var simpleClass = new SimpleClass();
var factory = Factory.Create();
Console.WriteLine(factory);

using var refStruct = new RefStruct();
using var simpleClass = new SimpleClass();
var factory = Factory.Create();
Console.WriteLine(factory);

using var refStruct = new RefStruct();
using var simpleClass = new SimpleClass();
var factory = Factory.Create();
Console.WriteLine(factory);

and output will be:
Created Factory!
Hello from class!
Hello from ref struct!