On Thu, Jul 26, 2012 at 4:48 PM, Dan Bron <j...@bron.us> wrote: > To understand why, we must recall that capped fork is a grammatical > _exception_.
Yes. Grammatical exceptions are common in J (all special code) and in natural language (where the idioms vary much more wildly than J's special code -- ideally, the only evidence of most special code in J will be in timing). > This is opposed to the concept that [: is invoked and its empty domain > somehow passes a "null" LHA to g which then (lacking a left argument) > applies itself monadically to the output of h . Yes. Here we have an example of introducing something of theoretical interest (a verb with an empty domain) and also introducing a use for it. > What that means is [: would serve to cap a fork, //no matter what its > definition//. In other words: provided it is a verb, [: could have any > definition at all. For example, the following sequence > > ([: +/ i.) 5 > 10 > [: 123 > 1 2 3 > (+/@:[:) 123 > 6 > ([: +/ [:) 123 > 6 > > ... would be perfectly legitimate, in the sense that we could > change the Vocabulary entry for [: to define it to mean > 10&#.^:_1 , without any impact on the interpretation or > function of capped fork. Except that capped forks can include uncapped forks and this approach would change the interpretation of uncapped forks. (Which you do acknowledge, later.) > [Aside to Raul: I'm sure you don't find any of this surprising, > but I just wanted to expand on some of the subtler points > for anyone reading this who isn't as familiar with the material.] Understood. > Maybe I should have presented this position -of constraining > my use of [: to capping forks- as a way to honor [: and its > purpose. Ok, I can see it as emphasis. And, similarly, I find myself uncomfortable adopting any emphasis mechanism unconditionally. I can go with "usually" but not "always". "Always" turns into "no information that's not already present". "Usually" turns into "I feel this is important in this context". > That said, the interpreter does take special steps to allow for > cap to have aliases, as in cap=:[: Yes. [Non-]Workalikes fail, but named instances work. Names, by the way, are another form of emphasis, from my point of view. Thanks, -- Raul ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
