It's not even a 3 years language yet, because well, people are not jumping all over it.

  ((jQuery "#content") `hide)

  jQuery('#content')['hide'];     // same as jQuery('#content').hide();

In your experience, is writing javascript as arc a feasible idea? or even a good one?

It is feasible, but there are tradeoffs. If you generate your scripts and markup in Arc, you get the benefit of having more of your code in uniform syntax, and it's often more concise. However, your system will be more dependent on Arc, such that if you decide to port to another language, it will be more work. You also give up a lot of the handy editor tools designed to help you write JavaScript/HTML/CSS by hand.

jQuery already takes so much of the verbosity out of writing JavaScript that it can feel a bit excessive to try and metaprogram it away any further.

Not really the same, it's missing the () from the end to call the function.

Adding another level of parens seems to do the trick:

    (((jQuery "#content") `hide))

    jQuery('#content')['hide']();

> jQuery already takes so much of the verbosity out of writing JavaScript that it can feel a bit excessive to try and metaprogram it away any further.

Agreed.

There are still annoyances though, like the anonymous function syntax when combined with function calls and json literals:

    jQuery(".item").each(function(){
              fn_that_takes_json({ id: $(this).id, obj: $(this) }); });

You're right, thanks for catching that.

The `#` in that jQuery selector condemns the Arc version to look worse than the code it's attempting to repair. If the selector didn't have special characters, as in

  jQuery('content').hide();

  (jQuery!content.`hide)

I don't know if macros can do this,

    (js
        (jQuery "#content"
            (toggle))        ;; translates to: jQuery("#content").toggle();
        (jQuery ".cue"
            (html "done")
            (addClass "t"))) ;; translates to: jQuery(".cue").html("done").addClass("t");

  (def jquery-dedot (symbol)
    (when (isa symbol 'sym)
      (zap string symbol)
      (when (begins symbol ".")
        (cut symbol 1))))
  
  (def parse-chain (chain)
    (whenlet (first-method-sym . rest) chain
      (iflet first-method jquery-dedot.first-method-sym
        (let numargs (or (pos jquery-dedot rest) len.rest)
          (let (first-args rest) (split rest numargs)
            (cons (cons first-method first-args) parse-chain.rest)))
        (err:+ "A chain given to 'parse-chain didn't start with a "
               "dot-prefixed method name."))))
  
  (mac jquery (selector . chain)
    (let result `(js-call js-var!jQuery ,selector)
      (each message parse-chain.chain
        (zap [do `(js-send ,_ ,@message)] result))
      result))
  
  (def js-var (name)
    (annotate 'rendered-js
      string.name))
  
  (def js-call (callee . args)
    (annotate 'rendered-js
      (+ "(" tojs.callee "(" (intersperse "," (map tojs args)) "))")))
  
  (def js-send (object method . args)
    (annotate 'rendered-js
      (+ "(" tojs.object "[" tojs.method "]("
         (intersperse "," (map tojs args)) "))")))
  
  (def tojs (value)
    (caselet type-value type.value
      rendered-js  rep.value
      int          string.value
      string       (do (zap [subst "\\\\" "\\" _] value)
                       (zap [subst "\\'" "'" _] value)
                       (zap [subst "<'+'/" "</" _] value)
                       (zap [subst "]]'+'>" "]]>" _] value)
                       (zap [+ "('" _ "')"] value)
                       (tostring:w/instring stream value
                         (whilet char readc.stream
                           (let code int.char
                             (if (<= 32 code 127)
                               pr.char
                               (let hex (coerce code 'string 16)
                                 (pr "\\u")
                                 (repeat (- 4 len.hex) (pr #\0))
                                 pr.hex))))))
        (err:+ "A value of type \"" type-value "\" can't be "
               "translated by 'tojs (yet).")))

  arc> (jquery "#content" .toggle)
  #(tagged rendered-js "((jQuery(('#content')))[('toggle')]())")
  arc> (jquery ".cue" .html "done" .addClass "t")
  #(tagged rendered-js "(((jQuery(('.cue')))[('html')](('done')))[('addClass')](('t')))")

One downside is all the parentheses this leaves. But if that turns out to be a problem, the thing I'd do is to rewrite the JavaScript-generating utilities to return meaningful AST objects rather than just tagged strings. That way, the AST can be pretty-printed in a separate step, once the context of each and every JavaScript expression is known.

An AST could also be good for displaying as debug output, minifying, verifying, compiling, translating to multiple programming languages, and doing any other kind of inspection. The format of the AST could also be set up to make it easier for different generated parts to avoid tripping over each other; for instance, there could be scopes for element IDs or a library dependency resolver.

  (mac rfn (name parms . body)
    `(let ,name nil
       (assign ,name (fn ,parms ,@body))))

  ; prints 1..10, each on its own line

  ((rfn foo (x)
    (prn x)
    (if (>= x 10)
         nil
        (foo (+ x 1))))
  1)

You were probably following the brief installation instructions at [2], which tell you to download Arc 3.0. If you download Arc 3.1 instead (see [3]), then you have more flexibility about which version of mzscheme to use. In any case, once you have installed mzscheme and downloaded/untarred arc3.[0|1].tar, you cd into the arc3.[0|1]/ directory (where as.scm resides) and run "mzscheme -m -f as.scm" to launch an instance of the Arc REPL.

To be sure, which operating system are you running?

---

[1] http://ycombinator.com/arc/tut.txt

[2] http://arclanguage.org/install

I did try the site for a bit, its quite cool. Was trying to learn some schema earlier on, but totally lost as to how to get arc to launch.

Well I'm glad I asked because the above instructions presume you're on a Unix-based system (Linux, Mac OS X) working from the command line.

Unfortunately, I'm not familiar with how to get Arc installed on Windows. Here's one guide on the topic [1], but I can't vouch for its accuracy. If you want to find more related resources, try using http://af.searchyc.com/ to search this forum for posts that mention "Windows".

By cd, do you mean the windows command prompt?

Yes. cd is a standard command on shells for both Windows and Unix to change the current directory.

---

1) Get Racket. http://racket-lang.org/

2) Get Arc. http://arclanguage.org/item?id=10254

3) Make a batch file that'll run an Arc REPL for me when I double-click it. Here's my batch file, with a boatload of comments to help you figure out what I'm doing: http://gist.github.com/576688 There's probably some room for improvement, but it's what I'm happily using at the moment. (Note that it crashes a bit if you close the terminal window while Racket 5.0.1 is running, instead of exiting via a Racket (exit) call or an Arc (quit) call. I think this is a Racket issue, since previous versions don't crash that way.)

4) Make some necessary changes to Arc so that it stops giving errors on Windows. There are two main issues here. For Arc to start at all, you'll need to fix 'setuid (http://arclanguage.org/item?id=10625). Then, if you also want to run web applications, you'll probably need to fix the system call to mkdir (http://arclanguage.org/item?id=4652), and I wouldn't be surprised if one of the other system calls breaks too.

Also, I highly recommend rlwrap. See this thread: http://arclanguage.org/item?id=10

I have added the following to my .bash_profile (probably the Mac equivalent of .bashrc):

  export PATH=/Applications/Racket\ v5.0/bin:$PATH
  alias arc='rlwrap -c -r -l ~/Documents/ARC_LOG -q "\"" -C arc racket -i -f ~/Dropbox/arc3.1/as.scm'

  (parameterize ((current-directory (current-load-relative-directory)))
    (aload "arc.arc")
    (aload "libs.arc") 
    
    (aload "sh.arc")) ;my stuff

Trying to figure out the dev\urandom problem now

What's the motivation for this? I'd say that the given addition example definitely sacrifices some usability because it takes so much longer to evaluate than if you had computed it in the browser. It also seems like this would make your web apps less scalable, since even the most trivial client-side scripts would consume server resources on a per-user basis. (And how would you do something like a JavaScript animation using this model?)

The actual language can do whatever. The language docs are here:

http://hc.fullpliant.org