Trivial C# class with a generic parameter wouldn't compile for no apparent reason

Question

I want a generic function that would work with types that have Top, Bottom, Right and Rect read-only properties - I have

Answer 1

You have to specify the base class that supports .Left in the where clause or you have to cast what to a type that supports the .Left-property:

internal class MyTemplate where WhatType : YourBaseClassWithLeftProperty

or

internal class MyTemplate {
  internal static void Work( WhatType what )    {        
    YourBaseClassWithLeftProperty yourInstance=what as YourBaseClassWithLeftProperty;
    if(null != yourInstance){
         int left = yourInstance.Left;    
    }

  }
  ...