In the department of wishful thinking:

type

TElement = class(TSomeClass)

Sibling: TElement;

end;

type

LinkAttribute = class(TCustomAttribute)

FLink: TElement;

constructor Create(aLink:TElement);

end;

TContainer = class

X1: TElement;

[Link(X1)] //<– wish I could use an attribute to link X1 with Y1

Y1: TElement;

X2: TElement;

[Link(X2)] //<– wish I could use an attribute to link X2 with Y2

Y2: TElement;

end;

It would be nice if attributes could reference class/record local fields or properties.

I know – it would put a lot of load on the compiler / linker.

If the compiler was two pass, order would not be important.

Since the compiler is single pass – perhaps something like

TContainer = class

[Link(forward Y1)]

X1: TElement;

Y1: TElement;

[Link(forward Y2)]

X2: TElement;

Y2: TElement;

end;

could be an option as well.

#MoreDeclarationLessCode