[racket] What about an Racket Artifacts thread?

From: Eli Barzilay (eli at barzilay.org)
Date: Wed Apr 25 20:17:39 EDT 2012

Two hours ago, Neil Van Dyke wrote:
> FWIW, some wiki/CMS *software* actually implemented in Racket (none
> of this kludgey TWiki or massive MediaWiki or such) has been quietly
> the next thing on my unpaid work TODO list, after I release McFly
> and my rewritten HTML templating libraries.
> I want the markup language for the wiki/CMS to use the Scribble
> reader (and probably Scribble subset language and formatter), to
> lower the barrier for people editing the wiki or authoring a PLaneT
> package to then go and do the other thing.  Most uses of a wiki
> installation would be hitting static files or blobs, and the Racket
> Web Server would handle editing and any tiny bits of JSON Web
> serving, so it could run a site like the official Racket wiki on a
> modest computer/VM.

I have a sketch of an implementation which I hope to finish this

* The language is the one in `scribble/html' (which is still not
  really public since it's undocumented, it still needs a few minor
  tweaks), but any other language can be used, and the output is used
  -- so it sticks to the "just use modules" principle, no hacks.  It
  also looks inevitable to implement a markdown parser, especially
  given that people will start using GH for bugreports.

* The rendering is doing just that: dumps the result to a file, so
  unless you're editing pages it's all static.  But this should be
  extended too, since I want it to have some gadgets like votes,
  access lists, etc.  The plan is to also have files that are not
  rendered as public pages (but are editable through the wiki).  This
  is so you can create a bunch of pages that use libraries that you
  can put on the wiki -- and also have some central library so that
  you could contribute site-wide library code if needed.

* For an editor, I basically hooked a simple textarea into an ajax
  call, so you have the editor at the top and a continuously updated
  HTML result rendered below.  (Ie, there is no "run" button.)  All
  evaluations are sandboxed, of course.  This didn't take much code to

But there's a bunch of stuff to be done:

* A backend system to save pages and revisions.  Using git is an
  obvious choice -- and maybe also allow pushing to a repo as a way to
  publish pages.  (The repo layout is unclear: a single repo means
  that there's no access restrictions, and lots of binary file work is
  not something that fits git.)  Also, implement uploading of files
  for binaries (possibly requiring some quota system to avoid the

* Some authentication facility.

* Dealing with edit conflicts.

* An editor that works better than a textarea.  I looked into a fewe
  fancy ones, then just went on with the plain choice to defer the
  decision.  Recently I looked into etherpad lite: it implements a
  better editor, but more importantly, if it's used as the editor then
  conflicts are resolved in a trivial way (they don't happen), and as
  a side bonus you get a live evaluator that you can edit with other
  people in real time.

  Etherpad (lite or not) by itself doesn't look like something that
  scales well, more than saving a lot of data, it's stuff that you
  don't want to see when you're done editing.  (IOW, you want to see
  changes between "revision steps", but there's no need to keep the
  history of editing steps almot at the char-by-char level.)  So I
  want to use it as an editor for as long as the file is being edited,
  and have a "save" button which saves revision; when nobody edits the
  page, the etherpad server can die, and the history is no longer
  needed.  (So it's used strictly for shared editing.)

And further down the road, it would be nice to add widgets like a page
that has some fixed code, and a lighter version of the editor
(smaller, no shared editing) which has the code required or used as a
language -- so you can make pages that will have some sample code, and
an interactive repl to try playing with the code.  There's also the
popular try-foo style pages that could be done similarly.

          ((lambda (x) (x x)) (lambda (x) (x x)))          Eli Barzilay:
                    http://barzilay.org/                   Maze is Life!

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