Operator as and generic classes

Question

I\'m writing .NET On-the-Fly compiler for CLR scripting and want execution method make generic acceptable:

object Execute()
{
  return type.InvokeMember(..);         


        

Answer 1

Is there a chance that Execute() might return a value type? If so, then you need Earwicker's method for class types, and another generic method for value types. Might look like this:

Nullable ExecuteForValueType where T : struct

The logic inside that method would say

object rawResult = Execute();

Then, you'd have to get the type of rawResult and see if it can be assigned to T:

Nullable finalReturnValue = null;

Type theType = rawResult.GetType();
Type tType = typeof(T);

if(tType.IsAssignableFrom(theType))
{
    finalReturnValue = tType;     
}

return finalReturnValue;

Finally, make your original Execute message figure out which T is has (class or struct type), and call the appropriate implementation.

Note: This is from rough memory. I did this about a year ago and probably don't remember every detail. Still, I hope pointing you in the general direction helps.