Hi, if I create a new matrix without assignment (matrix m), I get a 0x0 empty matrix. Can I rely on this behavior or is it in principle undefined and could change in the future?

Am 02.12.2022 um 10:37 schrieb Artur T.: > Am 01.12.22 um 17:06 schrieb Sven Schreiber: >> >> >> if I create a new matrix without assignment (matrix m), I get a 0x0 >> empty matrix. Can I rely on this behavior or is it in principle >> undefined and could change in the future? > > I would recommend to follow one basic programming principle: explicit > is better than implicit, meaning being concrete and specific instead > of abstract and general ;-) > > I think this is more explicit and _not_ expected to change: > > <hansl> >   matrix m = {} > </hansl> > Yes, in principle I agree. However, you can do "matrix m n o" on one line to create several objects, and you would need three separate lines being explicit. And I really like having less code lines, that's also what attracted me to Python in the past.

On Thu, Dec 1, 2022 at 11:06 AM Sven Schreiber <sven.schreiber(a)fu-berlin.de&gt; wrote: > if I create a new matrix without assignment (matrix m), I get a 0x0 > empty matrix. Can I rely on this behavior or is it in principle > undefined and could change in the future? You can rely on it. It's documented: see section 11.9 of the Gretl User's Guide.

The only other pertinent point to note is that while you can repeat a "null definition" such as "matrix m = {}" you cannot repeat a bare declaration in hansl (or not without first deleting the object in question) since that would seem to imply that you've forgotten that the identifier in question is already declared.