Re: [Gretl-devel] functions vs commands (was Re: Octave support)
On Thu, 25 Feb 2010, Allin Cottrell wrote:
On Thu, 25 Feb 2010, Riccardo (Jack) Lucchetti wrote:
> The gretl scripting language has grown through time
> considerably: the lack of coherence, if you will, is a
> consequence of the fact that it had started more as a
> convenience "batch" language to automate certain jobs, and
> gradually has become more and more similar to a programming
> language. Of course, since Allin and (to a much lesser extent)
> I were the people who put the features in, IMO it's only natural
> that the closer you come to a programming language proper, the
> more it looks like the programming language that we like the
> most (ie C), where _literally everything_ is a function.
Yes, exactly. But as we make gretl-script more C-like at the
margin, I'm very much aware that while this is to my liking it is
not very attractive to people with no programming background.
Agreed.
We could achieve consistency by scrapping "commands" and
making
everything a function, but I wouldn't favor that (and I don't
think Jack is suggesting it).
I am not: we'd end up with something very similar to Ox, which is a
fantastic program, but not one I would ask my undergrads to use. In fact,
I think that the a balance we have now is very very nice: gretl is usable
in no time by almost anyone, but OTOH it's become powerful and
flexible enough to be usable for research. To some extent, it's gone the
same way natural languages (eg English, Italian) have: adaptation to the
changing needs of the speakers (the users in the case of gretl) has
produced something that works despite being inconsistent and far from
logical.
The "command" mode is more relaxed
and less persnickety (less need for commas and parentheses and
such syntactical apparatus; more flexibility in the order of
arguments -- e.g. option flags can go anywhere).
Absolutely. On the other hand, whatever new functionality will be
available to gretl under the form of user-contributed functions will have
to be used through functions. You can only admire what the Stata guys have
done here: although I personally don't like Stata syntax very much, the
fact that you can put an ado file somewhere and magically a new command
appears is very cool.
Riccardo (Jack) Lucchetti
Dipartimento di Economia
Università Politecnica delle Marche
r.lucchetti(a)univpm.it
http://www.econ.univpm.it/lucchetti