Re: [Gretl-devel] redefining "NA"
On Tue, 21 Aug 2018, Sven Schreiber wrote:
Am 21.08.2018 um 22:09 schrieb Allin Cottrell:
>
> Gretl datafiles (gdt and gdtb) have for many years contained version
> information.
Right, very good.
> This hasn't been a big deal for the most part, because incompatible changes
> to the format have been few and far between. In the present case we've
> upped the gretldata version to 1.4, and the signal for current gretl to
> expect old-style NAs in a gdtb file is that its version is less than 1.4.
But does old gretl (or any gretl, for that matter) issue a warning if it
encounters "future" data file versions?
Good question. In a word, no, but that's something I've been
thinking about. It really hasn't been an issue so far. XML is very
flexible, and so long as older gretl can get what it's looking for
out of a newer gdt file (always the case to date) it can just ignore
any tags or elements that it's not expecting. Even now, with the NA
redefinition, it's only binary gdtb files that are affected. (The
case of Stata, I gather, is quite different.)
That said, it would be a good pre-emptive move to build in some sort
of warning mechanism: "This data file's version (%d) is higher than
the version (%d) that is fully supported by this build of gretl.
Some features may not be recognized correctly." -- or something like
that.
Allin