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A comment on Anarki – Community-managed fork of the Arc dialect of Lisp. Parent comment

Re:Anarki – Community-managed fork of the Arc dialect of Lisp by sago on Sunday July 15, 2018 @02:39PM (#17536403)
I don't know Arc, so this confuses me:

  arc> (map l '(0 1 2))
  (1 2 3)
What is the logic here? Is l made into a function that holds state and returns each element in turn (like an iterator function)? Because I would've expected:

  arc> (map l '(0 1 2))
  ((1 2 3) (1 2 3) (1 2 3))
In what way is map being applied here?
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Re:Anarki – Community-managed fork of the Arc dialect of Lisp by sago on Sunday July 15, 2018 @03:11PM (#17536526)
After RTFM, I can answer my own question:

> In Arc, data structures can be used wherever functions are, and they behave as functions from indices to whatever's stored there.

(quoted from the Arc tutorial)

So

   arc> (l 0)
   1
and so on. So the GP makes sense.
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Re:Anarki – Community-managed fork of the Arc dialect of Lisp by dmead on Sunday July 15, 2018 @05:11PM (#17537104)
that's confusing as hell. there's a reason this didn't take off (Besides the competition from clojure)
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Re:Anarki – Community-managed fork of the Arc dialect of Lisp by etatoby on Sunday July 15, 2018 @06:59PM (#17537571)
I don't like the Arc language because it's dynamically typed and thus inherently unsafe (see other threads for this sort of discussion.)

But I like this particular feature. If you think about it, an array is a mathematical function, or map, from indices to values. So it makes sense to be able to apply it to indices to get the respective values.

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Re:Anarki – Community-managed fork of the Arc dialect of Lisp by DavidSJ on Sunday July 15, 2018 @07:36PM (#17537726)
In that sense, map just composes its two arguments.
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Re:Anarki – Community-managed fork of the Arc dialect of Lisp by JadeNB on Sunday July 15, 2018 @08:39PM (#17537938)
That's cool! I'm a mathematician and so inclined to (over-)abstract programming, but it had never occurred to me to think of it that way.
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Re:Anarki – Community-managed fork of the Arc dialect of Lisp by sova on Monday July 16, 2018 @04:54PM (#17545011)
Learn you a lisp for great justice
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Re:Anarki – Community-managed fork of the Arc dialect of Lisp by quadcore on Sunday July 15, 2018 @05:45PM (#17537273)
It's kinda cool to be able to write (myarray i).
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Re:Anarki – Community-managed fork of the Arc dialect of Lisp by ScottBurson on Sunday July 15, 2018 @03:13PM (#17536539)
I think the list '(0 1 2) is behaving like the function — in CL syntax, sorry, I don't know Arc — (lambda (x) (elt '(0 1 2) x)). That is, the list is being treated as a sequence, which is a function from each index to the corresponding element.
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Re:Anarki – Community-managed fork of the Arc dialect of Lisp by jacobush on Sunday July 15, 2018 @04:41PM (#17536960)
Is PicoLisp the same?
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