After reading other people's responses in this thread, I thought I should expand on the concept of "forwarding".
First off, there are different kinds of forwarding. There's forwarding of results, and there's forwarding of definitions. To make this concrete, let's pick a specific example. 3 # *: 4 16 16 16 Here's 16 is the intermediate result from *: 4 and this result gets forwarded to # which in turn makes three copies of that result. Simple, yes? But let's say we wanted to make 3 copies of the definition of *: (or, technically: 3 copies of the symbols which represent the definition of *:) instead of making 3 copies of the result of *: 3 # *:`'' ┌──┬──┬──┐ │*:│*:│*:│ └──┴──┴──┘ Expressing this in english would probably go something like this: Original sentence: 3 copies of squaring Result: squaring squaring squaring So... again, this is simple. It's also a bit useless, which makes it seem nonsensical -- what are we going to do with these three copies? Using the copies wasn't really a part of the question, but J gives us various ways to use them. For example, we could use each one independently and stick all of their results together: (3 # *:`'')(`:0) 4 16 16 16 -- Raul On Mon, Aug 15, 2011 at 7:10 AM, Raul Miller <rauldmil...@gmail.com> wrote:I > On Mon, Aug 15, 2011 at 5:08 AM, Kim Kuen Tang <kuent...@vodafone.de> wrote: >> Are verbs ( dyad or monad) first-class citizen in j? > > The answer to this is "no" in the same sense that objects are not > first-class citizens in any object oriented language. > >> Is it possible to forward a verb to another verb? > > Yes. > >> Is it possible to box a verb into list ? > > Yes. > >> Is it possible to have a dictionary like the case in kdb? Something >> like : (`a`b`c)!(1 2 3) > > Yes, but not exactly. > > Typically, in J, locales are used for this purpose. But locales are > not values and can only be referred to (by name). > > You would have to implement a replacement for this use of ! as a user > defined verb. > > -- > Raul ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
