Crystallography Online: the website of the International Union of Crystallography

The CIF specifications could be simplified by dropping all of the
discussion about differences to STAR. With bracket delimiters and
possible MIME-based text, CIF will no longer be a subset of STAR anyhow.

Also, it would be nice to finalize other STAR left-overs like nested
loops. I noticed that the mmCIF NMR extension already uses nested loops.
Therefore, I think the best solution is to include nested loops in the
CIF syntax, but leave them as optional features, similar to the way
parsing of save-frames is not a mandatory feature. Likewise, GLOBAL_
should probably be dropped, or included as optional, possibly with
different rules from STAR.

I think it would also be good to allow nested save frames as an optional
extension, depending on whether anybody else thinks it is a useful idea.

Joe Krahn