anchor.diff:          Tests = [];
           Setups = [];
           TearDowns = [];
  +        ChildContexts = [];
       }
       let addTest ctx test = { ctx with Tests = test::ctx.Tests }
       let addSetup ctx setup = { ctx with Setups = setup::ctx.Setups }
       let addTearDown ctx tearDown = { ctx with TearDowns = tearDown::ctx.TearDowns }
  +    let addChildContext ctx child = { ctx with ChildContexts = child::ctx.ChildContexts }
   
       let rec perform_setup context =
           match context.ParentContext with
  
positive.code:         | None    -> []
          | Some(x) -> (context.Name)::(name_stack x)
  
  type TestCollection(_parent : TestCollection option, _name) =
      let parentContext = match _parent with
                          | None -> None
                          | Some(x) -> Some(x.getContext())
      let mutable context = TestContext.create _name parentContext
      let mutable contexts = []
      let mutable current = None
  
      member self.getContext() = context
  
negative.code:         Setups: testFunc list;
          TearDowns: testFunc list;
          ParentContext : T option;
          ChildContexts : T list;
          }
  
      let create name parent = { 
  