--- neville holmes <[EMAIL PROTECTED]> wrote:
>
> You can also imply the use of operands when defining
> operators (adverbs and conjunctions) tacitly, but this gets
> very awkward. Tragically, you can't use [. and ]. to specify
> operand use the way [ and ] specify argument use. Thus
> a conjunction like [.&{. ]. [.&{: cannot be clearly defined.
>
This was an early-morning email, and I realized as I was
showering that my example should have been
{.[.}.
so that the adverb
a =. {.[.}.
would allow f a x to apply f between the head of x and the
behead of x. Similarly, x f a y would use x {. y and x }. y as
arguments for f.
Other examples:
b =. ] ,: [. NB. adverb
then f b x would stack x over f x and x f b y would stack y
over x f y.
c =. [EMAIL PROTECTED] [. {:@[ ]. ] NB. conjunction
then 3 7 f c g y would effect 3 f 7 g y (and I intend this as
a top of the head example of defining a conjunction c which
could be used systematically for various kinds of series).
There are ways of defining such adverbs and conjunctions
without [. and ]. I suppose, but surely [. and ]. would make
such constructs much easier to produce and understand.
(The above are from memory; I haven't coded any J for
months now, more's the pity.)
Neville Holmes, P.O.Box 404, Mowbray 7248, Tasmania
Normal e-mail: [EMAIL PROTECTED]
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