Forward declaration

I think I'll drop my original question (since it's answered now :) thankyou all).

But I have a related question - What am I doing wrong here:

Type THouse
  Function Create()
    Self.MakeRoof
  End Function

  Method MakeRoof()
    'Some code
  End Method
End Type

The error I get is when calling Self.MakeRoof; "Identifier 'MakeRoof' not found".