Cell IDs and d.cellcreation

[Tuukka Hastrup <Tuukka.Hastrup@xxxxxx>]

Hello!

I'm implementing the d.cellcreation. Of course, the implementation
depends on what is actually wanted. At the moment, I've understood the
properties should be these:
- all the cells form a rank on this dimension, in creation order
- deleted cells should be represented by dummy cells
- the 1st cell on the rank is the home-cell of the space
- the last cell on the rank is the latest cell created
- given nth cell, the next cell is the one created after this cell

The problem at the moment is that the current ZZ-space implementations
give the second cell created some other number than 2. Why is that?

And considering the space implementations, I think we should move the
id booking operations into the ZZDimSpace because that's where
d.cellcreation is defined and it needs the ids anyway. IMHO
d.cellcreation should be taken as a general property of every ZZ-space:
- every cell created could be always referenced to - even after
possible deletion
- every cell could be easily referenced to - along the dimension, that
is - without the need to know the format of ids

By the way, is there this kind of dimensions already (required of
and defined for every ZZ-space)? Maybe d.clone? And what about d.1, d.2
and d.3?


Tuukka