On Tue, Aug 4, 2009 at 9:20 AM, neville holmes<[email protected]> wrote: > Raul Miller wrote: >>Consider: >> ? avg1=: +/ % # >> ? avg2=: [. % ]. >> ? avg3=: f % g >> >> if avg1 is a verb, and if avg2 would >> be a conjunction, what would avg3 be, >> and how could you tell? > > Isn't this a problem anyway ? (Even if avg2 is > ignored.) I seem to remember that if f or g aren't > defined then the J interpreter assumes they are verbs.
I thought the point of your proposal was to tacitly define adverbs and conjunctions? If J were to treat them as verbs, they would be useless. v=: + w w=: / v 1 2 3 |domain error: w Here, w is an adverb which J has decided to treat as a verb. Of course, if J treats w as an adverb, everything works fine. v f. |domain error v + w v=: + w v +/ >> ? 1: + 2: * 3: - 4: % [. ^ 6: >> >> If this train is an adverb, the top level fork >> which has + for its middle tine must be treated >> differently than if the train were a verb.? >> But neither of its other "verbs" are [. nor ]. > > Isn't it just > > ? (1: + (2: * (3: - (4: % ([. ^ 6:))))) Yes. > If you're worried about [. bringing in a noun > then you can require [. only to be used as an > operand, and then something like [."_ can be > used in a train. That was not the issue I was discussing here. The issue I was discussing here was whether J's mechanism for handling [: could be used for handling [. -- and the above example was illustrating one of the reasons this mechanism could not be used. >> But let us say the following are illegal: >> ? f=: [. >> ? g=: ]. >> >> This could avoid both of the above difficulties >> -- unless we insisted on using the mechanism >> which is used to handle [: > > You've lost me there. Sorry. Perhaps you are > saying that operations defined with [. or ]. should > not be nested ? No, once again -- I was talking about whether the mechanism used for [: would be useful here. >> That said, Neville has made lots of suggestions, >> and some of my above examples would not be allowed >> with some of his suggestions. > > I thought I'd only suggested [. and ]. to be used > to bring in operands, with the suggestion (as above) > that they could be required to be only used as > operands. Have I forgotten something ? For example, one of your proposal variants was that [. and ]. could not be used in trains -- that they could only be used as arguments to adverbs and conjunctions. -- Raul ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
