When is a slice not a slice?

[Philippe Sigaud via Digitalmars-d-learn]

>         enum b = DataAndView(1);
>         assert (!sameTail(b.data, b.view));

I suppose it's because enums are manifest constants: the value they
represent is 'copy-pasted' anew everywhere it appears in the code. So
for arrays and associative arrays, it means recreating a new value
each and every time.
In your case, your code is equivalent to:

assert (!sameTail(DataAndView(1).data,DataAndView(1).view));

And the two DataAndView(1), being completely separated, do not have
the same tail.