Structs as Generic Arguments

Question

I have several classes that implement something like an IAdd interface/class:

public class AddClass<T> where T : ISomething
{
   //Calculated Properties
   //Member Variables

   public Add(T t)
   {
       //do stuff thats complicated
   }
}

Now in some instances the t in Add(T t) just needs to be a simple struct with basically input variables; something like:

int ID;
string Name;
int Age;

From there I do some complicated stuff within the Add() method, but once I have 3 three inputs, I don't need anything else. I can probably just use a struct that implements ISomething. Is there a design pattern or anything that relates to this? Do I declare the struct within AddClass? What do I name it? Is there a standard approach for something like this?

Answer 1

t in this case would be considered a Parameter Object.

As for how you get an instance of ISomething, a DefaultSomething (either class or struct is fine, you probably want a class unless you have a good reason) is pretty normal to have. If the DefaultSomething is meant to only be used in the context of AddClass you could nest it, otherwise I would declare it on its own.

Answer 2

There are no type restriction which can define a struct. However, if you use the following restriction you have limited quite a lot:

 public class AddStruct<T> where T : struct, IConvertible, IFormattable, IComparable

I've blogged about it: http://blog.gauffin.org/2011/07/generic-type-restriction-for-enums/