J language is highly consistent, an empty frame is required when the rank of a verb is larger than or equal to the rank of its arguments.
An empty array is different from nothing as illustrated by some empty array jokes. On Jan 15, 2016 2:35 PM, "Matthew Baulch" <[email protected]> wrote: > And the dictionary defines frame.... such that it may be empty? I'm most > interested in whether, supposing this is the case, allowing empty frames > serve (an)other purpose(s) in the structure of the language. > > Apologies if my original phrasing was unclear. > > Every decision in the design of J seems very deliberate—which I really > appreciate. It just seems that empty frames must serve a purpose. Trying to > work it out. > On 15 Jan 2016 4:21 pm, "bill lam" <[email protected]> wrote: > > > The J dictionary is always correct. > > > > Пт, 15 янв 2016, Matthew Baulch написал(а): > > > Fair enough, though I can't work out whether the dictionary agrees with > > > NuVoc here or not. Either way, which definition of frame is correct? > > > On 15 Jan 2016 3:48 pm, "bill lam" <[email protected]> wrote: > > > > > > > For J implemention, the only authority is the J dictionary since > > > > it defines the J language. You need not worry anything else. > > > > > > > > http://www.jsoftware.com/help/dictionary/dictb.htm > > > > > > > > Пт, 15 янв 2016, Matthew Baulch написал(а): > > > > > I assume the intended definition of 'frame', in relation to verb > > > > arguments, > > > > > is that given on > > > > > > > > > > http://code.jsoftware.com/wiki/Vocabulary/FramingFill > > > > > > > > > > I'm just trying to understand verb/argument combinations with empty > > > > > frame--the most common case, I suppose. > > > > > > > > > > From the wording "each argument is ... an array of [r-cells]. The > > frame > > > > ... > > > > > is the shape of this array of [r-cells]", it seems that a frame > > should > > > > > never be empty, but in fact have a minimum shape of '1'. Of course, > > this > > > > > ties into the wording of many other statements. In the case of > dyadic > > > > > verbs, for instance, > > > > > > > > > > "frames must agree ... they must be identical or one must be a > > prefix of > > > > > the other" (stated in link above) > > > > > > > > > > as opposed to > > > > > > > > > > "frames must agree ... one must have shape 1 or be a prefix of the > > other" > > > > > (the way I see it, assuming equality implies prefix-of) > > > > > > > > > > Can anyone shed some light on this? Is there an important reason > for > > this > > > > > convention that I'm missing, or is it of little consequence? > > > > > > > > > > I'm implementing (or trying to...) a subset of J for the JVM, and > > this is > > > > > one little detail that's bothering me. > > > > > > > > > > Thanks. > > > > > > > > > > Matt Baulch > > > > > > > ---------------------------------------------------------------------- > > > > > For information about J forums see > > http://www.jsoftware.com/forums.htm > > > > > > > > -- > > > > regards, > > > > ==================================================== > > > > GPG key 1024D/4434BAB3 2008-08-24 > > > > gpg --keyserver subkeys.pgp.net --recv-keys 4434BAB3 > > > > gpg --keyserver subkeys.pgp.net --armor --export 4434BAB3 > > > > > ---------------------------------------------------------------------- > > > > For information about J forums see > http://www.jsoftware.com/forums.htm > > > ---------------------------------------------------------------------- > > > For information about J forums see http://www.jsoftware.com/forums.htm > > > > -- > > regards, > > ==================================================== > > GPG key 1024D/4434BAB3 2008-08-24 > > gpg --keyserver subkeys.pgp.net --recv-keys 4434BAB3 > > gpg --keyserver subkeys.pgp.net --armor --export 4434BAB3 > > ---------------------------------------------------------------------- > > For information about J forums see http://www.jsoftware.com/forums.htm > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
