Wouldn't fit !. be a fitting choice for modifying insert and co to have the
wanted behaviour?
Seemingly currently, !. doesn't do anything to any of the / and \ families,
and would therefore be free for use.
Just my 2 cents
Jan-Pieter
On Sun, 4 Mar 2018, 20:43 Raul Miller, <rauldmil...@gmail.com> wrote:
> I was thinking of `. as a modifier for / /\. and a few other adverb
> sequences, to provide the initial value (which matters when it would
> be a different shape, or type, from the sequences being operated on.
>
> Taking this the next step, let's maybe use O: to introduce v - O:
> would be similar to @: but would be for use in folds. v O:u/\.`. would
> be my alternate syntax proposal for u F::v
>
> I'm not sure, yet, that this is better, but I'd like to at least talk
> through the issues.
>
> Well, ok, it *is* better in the sense that my proposal introduces less
> new vocabulary, and takes advantage of visual similarity in a way that
> the F. F.. F.: F: F:. F:: proposal does not. But the specific details
> might be too gimmicky - for example, it might be better to instead
> have a `. and a `.: for example, where the `. is an adverb and the `.:
> is a conjunction (whose right argument is v).
>
> Thoughts?
>
> Thanks,
>
> --
> Raul
>
>
>
>
> On Sun, Mar 4, 2018 at 12:38 PM, Henry Rich <henryhr...@gmail.com> wrote:
> > OK, now we are getting somewhere. I am moving this back to Programming
> > (because I don't follow Chat). To your points:
> >
> > 1. Often unnecessary: agreed. Fold will not replace u/ etc.:
> > a. it's too wordy
> > b. The many ingenious optimizations in u/ will not be provided, at least
> > not initially
> >
> > 2. If v is an identity, who would need Fold?
> > a. often true, and they wouldn't use it then
> > b. but using Z: to control iteration may be convenient
> > c. Fold allows iteration front-to-back, avoiding &.|.
> > d. Fold allows specifying an initial value for the first application of
> u
> >
> > My expected application for Fold is when u is NOT a primitive. It might
> be
> > tacit or explicit, but u is going to be called for each item of y. Fold
> > gives a terse way to express its computation: the question is whether
> those
> > computations are common enough to justify the work. I agree with
> Marshall
> > that they are.
> >
> > I am open to your second-conjunction idea, though I don't see how it
> would
> > work. I considered making Fold a set of adverbs using a gerund u before
> > settling on the proposal as written.
> >
> > I have expanded the proposal to allow v to be a noun n, which would
> execute
> > n&{:: .
> >
> > Henry Rich
> >
> >
> >
> > On 3/4/2018 11:56 AM, Raul Miller wrote:
> >>
> >> I see where you are going with this now.
> >>
> >> And, I do like the thinking. (I'd have to think a bit more, though, to
> >> come up with good examples, for documentation purposes.)
> >>
> >> That said, this seems like it would be unnecessary in a good number of
> >> cases - only the "scan-like folds" really make good use of it, and
> >> then only when v is not an identity function.
> >>
> >> Perhaps, instead, if we can dip into symbolism a bit more, we could
> >> introduce a second conjunction that modifies folds at the "generate
> >> intermediate result" stage?
> >>
> >> [Does this description make sense?]
> >>
> >> Thanks,
> >>
> >
> >
> > ---
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> > http://www.avg.com
> >
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