using "instance" field

[maxtoroq]

While using static is a nice feature, static classes have inherent limitations. I think the same idea can be applied to fields, or even properties. e.g.:

class Program {

   using readonly TextWriter log = Console.Out;

   public Program() { }

   public Program(TextWriter log) {
      this.log = log;
   }

   public void Run() {
      WriteLine("Starting");
   }
}

I understand this looks a lot like #114, but it's a completely different feature. Unfortunately, the using keyword has already too many uses.

Also, if #218 is implemented, then it would be better to not have it on the member declaration, but on it's own using declaration, e.g.:

class Program {
   using instance log;
   readonly TextWriter log;

In the above example, the instance keyword is used to specify a member of the current type.

[CyrusNajmabadi]

i don't understand how your first example is different from:

class Program {
   // using -> private
   private readonly TextWriter log = Console.Out;

   public Program() { }

   public Program(TextWriter log) {
      this.log = log;
   }

   public void Run() {
      WriteLine("Starting");
   }
}

[bondsbw]

@CyrusNajmabadi Looks like it is the WriteLine, yours would need to be changed to

public void Run() {
   log.WriteLine("Starting");
}

[bondsbw]

This can also be accomplished for individual methods via

Action<string> WriteLine => log.WriteLine;

but the proposal would provide a way to bring everything into scope instead of just a single member.

[bondsbw]

If we add access modifiers (e.g. public using) then we effectively have an implementation of member delegation:

var program = new Program(myLogger);
program.WriteLine("Some string");

[maxtoroq]

@bondsbw

If we add access modifiers (e.g. public using) then we effectively have an implementation of member delegation:

That's not the purpose of the feature, it should work like using static, e.g. WriteLine is only visible in the (partial) class where the using declaration is present.

[bondsbw]

Fair enough. But if member delegation is more popular, influencing its design might get your proposed feature for free.