I don't see that the cases you mentioned are relevant. I very seldom see even f"g; f"f, never.
----- Original Message ----- From: Dan Bron <[email protected]> Date: Wednesday, November 10, 2010 7:30 Subject: Re: [Jprogramming] Atop u...@v with v of negative monadic rank To: J Programming <[email protected]> > Why would you ever say x+0 or y*1 ? > > -Dan > > > Please excuse typos; composed on a handheld device. > > -----Original Message----- > From: Roger Hui <[email protected]> > Sender: [email protected] > Date: Wed, 10 Nov 2010 07:13:04 > To: Programming forum<[email protected]> > Reply-To: Programming forum <[email protected]> > Subject: Re: [Jprogramming] Atop u...@v with v of negative monadic rank > > When would you ever say f"f ? > > > > ----- Original Message ----- > From: Zsbán Ambrus <[email protected]> > Date: Wednesday, November 10, 2010 7:06 > Subject: Re: [Jprogramming] Atop u...@v with v of negative monadic rank > To: Programming forum <[email protected]> > > > On Wed, Nov 10, 2010 at 3:15 PM, Roger Hui > <[email protected]> wrote: > > > The change you propose is non-trivial and has consequences > > > that may surprise you (and many others, I expect). > > > > > > Suppose f is <"_1, and you make the "combining rank" of > > > f be_1 instead of the current_ . > > > > > > So the ranks of ]...@f would be_1 (_1_1_1). Suppose the > > > argument x is i.2 3 4. Since the ranks of ]...@f are_1, > > > x is split into the cells i.3 4 and 12+i.3 4 and you apply > > > ]...@f to each cell. [...] > > > > You're right in that combining ranks shouldn't have negative > integers,> because that too would make (f"f) mean something > different from f, > > such as in the case when (f=:<"_1). I accept that that > > change would > > be a bad idea, so I retract that part of my suggestion. > > > > On the other hand, are there many surprises or > incompatibilities even > > if you take only the weaker variant of my proposal? That > > says that if > > rl is a negative integer and rr is a nonnegative integer, the diadic > > combining rank of f"(rl,rr) should be (__) instead of > > (_,rr). For > > example, the combining rank of (]"__3 7) would be (__ > >_). The case > > with left and right swapped would be handled similarly. > > The combining > > ranks would still always be nonnegative. > > > > As I said, this too would be better than the current state > > because it > > would help uphold the f -: f"f identity, which the current semantics > > does not do for such verbs. > > > > Ambrus ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
