Of course this would probably be quite a bit of an undertaking.

To create an arc equivalent you probably need build an arc library which provides some code inspection/dissection capabilities and ideally also be able to attach metadata to any given function or macro. With such a library you then build a script to auto generate the docs.

As for GitHub syncing; well no, I'm guessing users would need to trigger the script and then check in the updated docs.

This is still better for a few reasons...1. developers can generate docs, locally, that are in sync with the code base they are actually using (checked out or branched). 2. Even if the online docs gets out of sync for a while you're still only a script trigger away for updating all outstanding changes.

When arc advances enough to appease you, it will also be appealing to others; then when a larger community develops around arc you will start to have bad experiences. That's the nature of mass appeal.

Even pg noticed the quality of HN's content and community degraded with popularity, which is why he's adding the pending change discussed (amongst others).

Even Yegge's post would seem[1] to confirm this with his own data:

  Assembly language: Batshit liberal.
  Perl, Ruby, PHP, shell-script: Extremist liberal.
  JavaScript, Visual Basic, Lua: Hardcore liberal.
  Python, Common Lisp, Smalltalk/Squeak: Liberal.
  C, Objective-C, Scheme: Moderate-liberal.
  C++, Java, C#, D, Go: Moderate-conservative.
  Clojure, Erlang, Pascal: Conservative.
  Scala, Ada, OCaml, Eiffel: Hardcore conservative.
  Haskell, SML: Extremist conservative.

1. I assume arc to be like lisp. Many of the things that need a new interpreter atop scheme (lisp-1, quasiquote, unhygienic macros) are borrowings from lisp. The only major scheme-ism arc retains is call/cc. Am I missing anything?

2. I actually think arc is more batshit liberal than traditional lisp. Perhaps I'm reading too much into the absence of a module system, but I consider it a deliberate omission.

- They are both Lisps with dynamic type handling, prefix notation, strings as sequences, heavy use of hash-maps, a large number of functions and macros with similar names doing the same things.

- The syntax's are so similar you could pretty much swap out color scheme templates (in fact I initially used the arc textmate bundle for Clojure).

- They both depend upon pre-existing language for compilation. Clojure drops into java, Arc drops into scheme.

- The online comparisons between them are more frequent than arc and any other language.

I could go on, but I think you get the point.

And while I know you could create a list to show differences I'm simply saying that overall they are very similar which was my initial claim.

As for "having to be more like Clojure" to advance, well no, but I'm pretty sure that it's more likely than any other unstated options. Here's what I do see to support this:

- pg himself has stated Clojure is bringing LISP back into popularity and recommended clojure for use over other languages. (https://news.ycombinator.com/item?id=1804145, https://news.ycombinator.com/item?id=4486880)

(There's a lot of red herrings in your comment, though. That they look the most similar syntactically isn't too surprising, and it's irrelevant that erlang can't compete, or that they build on an existing language, etc. You're measuring position to compare trajectories.)

In any case, it feels quite delusional to compare arc to clojure at the moment :)

I realize many of my arguments have holes in them when viewed independently, but when put together those “soft arguments” contribute to painting an overall picture that supports my claim better than had I not given them. Albeit the "they build on an existing language" is pretty weak overall.

> “You're measuring position to compare trajectories”

Position is not something you can measure it's something you can map/use. That aside, I don’t believe what it is I think you intended to say is true. I used position to substantiate the claim of similarity, I used trends to substantiate the trajectory (i.e. the last half of my reply, what people are saying and what they are doing are trends).

> "if you have Clojure why do you care about arc?"

I like both languages. I don’t use Arc because its unfinished and unusable for the things I need to do. I often get the sense that when I promote Clojure on the Arc forum that people get defensive and wonder why I'm even around, but remember I am only saying what pg himself is:

  > Would you recommend Arc to modern startups in general?
  PG: No, I don't think so, not in its current state.
  > Why not?
  PG: It's still missing some things that most people take for granted.
  > Are there any Lisps you would recommend.. ?
  PG: Clojure is probably the best bet...

If you think arc is whatever pg says it is, then what we are saying and doing here is irrelevant :)

If you think arc is whatever we're saying and doing here, the things we take from clojure seem a tiny minority compared to the sum total of conversations. I'd say arc starts out kinda like clojure, but is looking to steal ideas from all sorts of languages including erlang.

---

I tried to phrase my question very carefully to avoid seeming defensive about something I don't care about. So let me just come out and say it: I have no problem with you talking about clojure all you want here. If you did, maybe I'd get to talk to you more! :) Arc is indeed absolutely unfinished, no disagreement there either.

Maybe what I'm actually defensive about is the prospect of any two languages becoming more and more similar. That just seems bad, nothing good can come of it. I'd rather see arc and clojure evolve in different directions and give me more ideas and more data about how good those ideas are.

Copying ideas and creating hybrids is totally fine, that's what we are good at. But then the hybrid starts at the intersection of its influences and sets off on a whole different trajectory.

So let me rephrase my question: is there something you miss from arc in clojure that has you wishing for a superset?

And I'm suggesting more care be taken in this regard, because it leads to you being offended (i.e. "If you think arc is whatever pg says it is, then what we are saying and doing here is irrelevant...") on statements that should be considered only in relation to the thread. It also leads to unintentional attacks such as "In any case, it feels quite delusional to compare arc to clojure ...". I don't think you realize you suggested I'm being delusional by adding that comment... Arc and Clojure are both modern lisps that have eliminated the overuse of brackets, so really is it delusional to suggest these two languages are more similar than not? Am I creating some injustice by telling someone, that's already leaning towards Clojure, that these languages are very similar anyway?

I'm going to end this thread here as I think it has already gone off the rails.

I might be interested in working on something like packages.el for emacs that supports grabbing arc libs directly from github.

  These parentheses weren't decorative though, 
  they exposed the structure of the code, and they are a
  minimal price to pay for extra clarity.

My path to clarity is as follows: I first scan code at a high level, often referred to as speed reading[1] where I find having more parentheses simply gets in the way. The second is using fixation[2] where I stare at a small block of code. With both Arc and Clojure I have no trouble moving from scanning to fixation then to understanding (clarity). It could be that the author struggles with his/her reading method. Chances are the author learned with traditional L.I.S.P (Lots of Infuriatingly Stupid Parentheses) and therefore the newer lisp dialects are working against his/her read training. I however started with Arc & Clojure and I therefore experience the same lack of clarity when reading the traditional LISP dialects. To each their own.

1. http://en.wikipedia.org/wiki/Speed_reading

The point I was making in the blog is expressed more eloquently in [1], but to summarise: the difference between LISP and the countless languages that have risen and fallen during LISP's lifetime is that LISP directly represents the parse tree. By disposing of those parentheses in the (if ) statement, Arc has introduced the need to count the terms in the list to understand the sense of the code, in other words to parse it. Clearly the same is true of Python, C++, Haskell and many other languages I respect, but by placing a barrier between the code and the parse tree, Arc has abandoned the principle that makes LISP a global, rather than a local, minimum in the history of programming languages, and I think this is a mistake.

  homogeneous list of any number of X
  fixed-length heterogeneous list of (X Y Z)
  expression... which fits one of these patterns:
    atom
    call to X with args Y

  map from X to Y
  homogeneous vector of any number of X
  vector alternating between X and Y, with no excess (like a map)
  call to 'cond with args alternating between (expression) and
    (expression), with no excess
  call to 'case with args starting with (expression), followed by
    alternations between (anything) and (expression), perhaps with
    (expression) as excess
  function body which might begin with a docstring and/or a metadata map
  destructuring syntaxes
  ...

For structured editing -- what you pursue -- we probably want even more static structure than what we want for auto-indentation.

I don't want to prod you to spend your time writing tools for niche languages or designing niche languages of your own, if that's not what you already want to do, but I'd like to ask what kinds of hypothetical languages you would like best....

Would you be eager to work with a lisp-like language where the AST has a few built-in notions of homogeneous lists, heterogeneous tuples, function calls, etc.? For instance, Lark defines an alternative to s-expressions that's more tailored to the ways the syntax is actually used (https://github.com/munificent/lark).

On the other hand, would you be eager to work with a language where the AST has an endless variety of possible cases, which can be extended by any programmer who wants to write an editor widget? Racket does something related to this, because it has an expressive pattern language for writing macros, and macros written this way generate good parse errors automatically (http://docs.racket-lang.org/syntax/Parsing_Syntax.html).

i.e Programmatically[1] yes you might need to count terms, but for code readability I do not count the terms I let code indentation guide me.

I can certainly see how this code indentation factor may be seen as too free in form or structure to be appealing to many, but having less parentheses is a huge readability/enjoyability win. A win that, at least for me, leads to huge gains in productivity.

Also, you do have the option to pretend the token count is even:

  (def example (x)
    (if (is x 1) "One"
        (is x 2) "Two"
        'else  "OOPS"))
  

I've also extracted the _ handling into a new function called (ugh) functionize. And I've fixed zap to show how you can make other functions "_ aware".

But like I said, this isn't as valuable in arc since you already have the [.. _ ..] syntax. All it permits is more widespread ssyntax use. You can say _.x instead of [_ x], and you can chain ssyntax around obstacles.

-

== Problems with functionize in general ==

The functionize-based utilities are discontinuous about the way they detect underscores: The body can use _ three times, or two times, or one time, but as soon as it uses _ zero times, it means something completely different. Thanks to this, I can break several layers of code by making a single local edit. But will I? Yes:

The 'treemem function detects occurrences of _ without regard for quoting or local scopes. So if I use an _ to activate one functionize-based utility, then I'll accidentally activate all the other functionize-based utilities which surround that one. If I want to avoid refactoring several layers of code each time I edit, I pretty much have two options:

- I can avoid putting an _ anywhere in my code, in which case this functionize feature won't be very useful to me.

- I can make sure to activate each and every functionize utility as soon as I use it, in which case they would have been better off as 'let variants. For instance, I might settle on the idiom (zap (do '_ ...) foo), but it would be more convenient to say (zaplet orig foo ...).

-

== Problems in Arc ==

Your Anarki commit is one of those things that is "guaranteed to break all your code." Personally, I like using the pattern (zap [map [...] _] args), which now breaks since the _ activates zap's automatic function wrapper. It seems you would want me to write (zap (map [...] _) args) instead, but for compatibility with Rainbow, Jarc, etc., I think I'll define a macro (itfn ...) and write (zap (itfn:map (itfn:...) it) args). Effectively, I'll be recreating the [...] functionality in the way I like.

Meanwhile, Arc already covers a lot of the functionality of Clojure's -> and ->> operators using (aand ...). If you still miss -> or ->>, I recommend just implementing an 'aand variant that doesn't short-circuit on nil. Call it 'ado or something.

Here's how to use 'aand/'ado with the examples from that thread you linked to (http://arclanguage.org/item?id=18044):

  (-> (range) [map [* _ _] _] [filter even? _] [take 10 _] [reduce + _])
  (-> 5 [+ _ 3] [/ 2 _] [- 1 _])
  
  (ado (range) (map [* _ _] it) (filter even? it) (take 10 it) (reduce + it))
  (aand 5 (+ it 3) (/ 2 it) (- 1 it))

== Considerations in Wart ==

Clojure's -> and ->> operators are not infix, and that might be good for their indentation. I'm not really sure.

  (-> (...)
    (...)
    (...
      ...)
    (...))
  
  (...) ->
    (...) ->
    (...
      ...) ->
    (...)
  
  (...)
    -> (...)
    -> (...
         ...)
    -> (...)

  (...)
    -> (...)
    ->> (...
          ...)
    -> (...)

I can only defend myself against the wart section :) In wart the pipe operator can only take two args and is intended to be used in infix. I use a non-infix transform for more args, and for prefix mode in general: https://github.com/akkartik/wart/commit/ec0f9a38b8

Oh, so you're pursuing both options at once. I look forward to you figuring out what kind of indentation you prefer here. :) My "considerations about wart" section was only wishy-washy anyway.

---

"For the rest, my weak defense is that functionize and the _ syntax is only intended for tiny expressions."

In Penknife, when I used the a'b operator as sugar for (b a), I found I ended up with a few really long lines of a.b.c'd'e.f, so it kinda suffered from its own success. ^_^ My a'b is the same as your (a -> b._), and it exactly corresponds to your no-underscore special case, (a -> b), so I expect you to have the same issue.

I suspect these syntaxes actually have a special tendency to let sugar accumulate, driving them away from the ideal "tiny expressions" case. Specifically, they make it possible to inject new code without breaking apart the surrounding sugar first:

  a.b.f.c.d                  # before refactoring
  a.b."foo".c.d              # illegal
  a.b -> (_ "foo") -> _.c.d  # legal? (not quite the example you gave)
  a.b'[itfn:it s.foo].c.d    # Penknife code of similar generality

Here's my current thinking: https://github.com/akkartik/wart/blob/aec0af2676/082macex.wa...

"these syntaxes actually have a special tendency to let sugar accumulate, driving them away from the ideal "tiny expressions" case."

Definitely. The wart example you gave is indeed legal, but the actual _ expression is still simple, even though the chain is long.

It seems nested expressions often work fine because each macro only wraps its arg and leaves the rest to the inside.

  (zap (map car._ _) (list list.1 list.2)
  => (zap (fn(_) (map car._ _)) ..)
  => (zap (fn(_) (map (fn(_) car._) _)) ..)

Some other concrete examples I came up with of the problems you pointed out:

  (zap (cons? & (fn(_) ..)) ..)  # broken by nested scope
  (zap (cons? & (fn(x) (+ '_ car.x)) ..)  # broken by quoting

  (mac functionize (expr)
    (if (and (treemem '_ ssexpand.expr)
             (~caris expr 'make-br-fn)
             (~caris expr 'fn))
      `(fn(_) ,expr)
      expr))

  arc> (= x '((1) (2) (3)))
  arc> (zap [map [car _] _] x)
  arc> x
  (1 2 3)