tea.mathoverflow.net - Discussion Feed (What benefit do we get from using markdown?)

Andrew Stacey comments on "What benefit do we get from using markdown?" (5579)

Andrew Stacey — Sun, 16 May 2010 13:03:52 -0700

I'm really pleased to read all that.

That the word (abbreviation?) "MathML" occurs so often is progress for me. Now I just have to convince you to ditch the word "javascript".

There really is no need to do any of this with javascript. Once you get your hands on the markdown code (and I consider this discussion relatively academic until that happy day), then you can simply choose to convert the latex-lite into MathML or other format according to what the end-user can see. That way, you server MathML to those who can see it, and Something Else to those that can't. You could even send the bare source if someone really wanted to see that. (Though anyone claiming that they can "read" LaTeX source more easily than anything else has never tried looking at the source of one of my papers. What they really mean is "latex-lite" but then that's what we're talking about here as well.)

All that is possible and is possible server-side. And it should be done server side, not client side. There are lots of reasons why so, but perhaps the biggest is speed. If it's done server side, the conversion can be cached and then everything gets so much faster and slicker. You do the conversion once per post per format, and that's that. All done.

But let me reiterate this point: all of this is completely possible once you get access to Markdown. Indeed, it's what we now do on the nForum: MathML to those that can, SVG/PNG to those that can't. Maximum accessibility, maximum customisability, maximum useability. Oh, and zero sugar, of course.

Anton Geraschenko comments on "What benefit do we get from using markdown?" (5574)

Anton Geraschenko — Sat, 15 May 2010 11:00:05 -0700

@Scott: I thought that instead of (3), the plan was

3') Hope that it eventually becomes possible to have the server translate latex input to mathml, and serve mathml directly to everybody. MathJax will "convert" this to MathML (i.e. leave it alone), or html+css for older browsers, via javascript.

The downside is that users without a MathML-capable browser and no javascript will see MathML instead of LaTeX. We could user a user-agent string and/or a preference as additional lines of defense against this problem.

Scott Morrison comments on "What benefit do we get from using markdown?" (5570)

Scott Morrison — Sat, 15 May 2010 09:16:27 -0700

@Andrew,

I think we've decided that the optimal future track (given the constraints of our access to the underlying software) is:

1) switch from jsmath to mathjax, when mathjax is ready. The server will provide math surrounded in $ ... $, in the latex input form. Mathjax will convert this to either MathML, for the browser to interpret, or html+css for older browsers, via javascript. Users without javascript will just see latex source.

2) hope that eventually we have access to the markdown engine on the server, and have it not look inside $ ... $.

3) hope that it eventually becomes possible to have the server translate latex input to mathml, and serve mathml directly, but only to users who have set a preference requesting it (or have a user-agent string that reliably predicts mathml support).

Andrew Stacey comments on "What benefit do we get from using markdown?" (5552)

Andrew Stacey — Fri, 14 May 2010 04:23:07 -0700

@Scott: I prefer to think of it as "'it looks alright to me' is the enemy of the best".

If you take a look at the nforum now, you'll see that it is possible to have ones MathML and see it, too.

Scott Morrison comments on "What benefit do we get from using markdown?" (5364)

Scott Morrison — Wed, 05 May 2010 09:01:38 -0700

@Andrew: I think we have a case of "perfect is the enemy of best" here.

Andrew Stacey comments on "What benefit do we get from using markdown?" (5351)

Andrew Stacey — Tue, 04 May 2010 13:50:59 -0700

Markdown shouldn't look inside mathematics, but the right solution is to tell Markdown about dollars, not about circumventing the code block methods. Markdown does look inside code blocks so using backticks is not guaranteed to be clean. The right solution is for the Markdown and mathematics converters to be integrated so that they both know about the other. Unfortunately, that's only possible if one has access to both.

François G. Dorais comments on "What benefit do we get from using markdown?" (5349)

François G. Dorais — Tue, 04 May 2010 12:15:52 -0700

I do use markdown regularly now that I learned how to use it, but I can't think of a reasonable use of markdown inside math. Couldn't the editor simply backtick all math?

Anton Geraschenko comments on "What benefit do we get from using markdown?" (5348)

Anton Geraschenko — Tue, 04 May 2010 12:05:30 -0700

I actually find markdown emphasis useful, and so do other people: a cursory look at a recent database dump shows that 19763 lines in posts used *, and only 4202 of those were between dollar signs (and that's an overestimate because I used a dumb regular expression which can't tell if you're within math or simply between math).

Since the only problem is when * or _ appear in math, the right solution is really to have the server ignore special markdown characters within math. As Scott said, help at the server end is not impossible in the long term, but I don't know how long it would take to push something like this through. It's even possible to modify the editor so that it automatically inserts backticks around math that looks like it might cause trouble, but I'm not very excited about trying to implement and maintain that.

Scott Morrison comments on "What benefit do we get from using markdown?" (5341)

Scott Morrison — Mon, 03 May 2010 22:27:25 -0700

A nice solution might be to do something like what happens here: a checkbox at the bottom of the "post" form so you can indicate that your text should be formatted with or without markdown. It would require help at the server end, but such things aren't impossible in the long term. This also avoids the backwards compatibility issue, and the software could remember your preference.

Andrew Stacey comments on "What benefit do we get from using markdown?" (5330)

Andrew Stacey — Mon, 03 May 2010 06:13:17 -0700

Which is why it's better for individuals to know how to turn it off than for the admin to enact it themselves.

Still, I think that your point about better integration between markdown and (whatever-produces-maths) is valid, just not possible with the current set-up.

Andrea comments on "What benefit do we get from using markdown?" (5329)

Andrea — Mon, 03 May 2010 04:20:17 -0700

@Peter: I actually use both * (or _) and **

Andrew Stacey comments on "What benefit do we get from using markdown?" (5325)

Andrew Stacey — Mon, 03 May 2010 00:00:50 -0700

(And in posting that here, I've just demonstrated that the Markdown implementation is not quite right: I wrote "

" in backticks in the hope that it would display as "

", but because of the way the implementation is done here, it got translated into "<p>".)

Andrew Stacey comments on "What benefit do we get from using markdown?" (5324)

Andrew Stacey — Sun, 02 May 2010 23:57:19 -0700

If n* can make markdown and latex work together, then why can't we?

For the simple reason that over at the nStuff, I have complete control over everything that is installed. (Fortunately, for the nLab, I don't have to since Jacques Distler already writes darn good software, but the nForum is extensively extended; fortunately, it is designed with such extensions in mind.) But here at MO, Anton only has limited control over what's there.

By the way, Markdown modifies the list numbers so that you don't have to remember to adjust them if you go back and insert something half-way through. So if I write a TODO list:

1. Define "wibble"
2. Prove that every "wibble" is a "wobble"
3. Deduce Riemann Hypothesis

and then decide that I ought to add in a step between (2) and (3) then I can just write

1. Define "wibble"
2. Prove that every "wibble" is a "wobble"
2. Explain relevance of "wobbles" to the axiom of choice
3. Deduce Riemann Hypothesis

and not have to rejig my numbering scheme.

Markdown does it's best to "play nice". One useful feature of it is that it respects "keep out" signs. If you want to turn Markdown off in a paragraph (or larger) then you can, simply by enclosing the whole section in <p> tags. It's hard to illustrate here, but just try experimenting and you'll see.

Over at the nForum, we're enlightened and allow you to put in any XHTML code that you want (I run it through a sanitiser to strip out nasty stuff). Here, XHTML code gets automatically stripped so I can't demonstrate it, whilst the SE/SO software has a very limited whitelist of allowed code. So I can't demonstrate all the possibilities of Markdown (or Markdown+maths) here or at MO, but at the nForum we have some Scrap Paper where you're welcome to doodle.

In particular, on MO and the nStuff, you can type a list using proper XHTML code (<ul>s and all that), but only at the nStuff could you modify the style (via inline CSS) of those lists so that your own numbering scheme was preserved.

Peter McNamara comments on "What benefit do we get from using markdown?" (5322)

Peter McNamara — Sun, 02 May 2010 20:07:16 -0700

@Scott: I understand that backwards compatability would be an important issue. Though I would hope that in this case, backwards compatability would not be too problematic (does anyone actually use the symbols of * and _ in their markdown form?) and perhaps even old posts could be grandfathered, if technically possible

@Harry: Actually you bring up something else I don't like about markdown, namely the way it handles lists. In particular, markdown should never take the numbering I give to a list and change it.

If n* can make markdown and latex work together, then why can't we?

Andrew Stacey comments on "What benefit do we get from using markdown?" (5291)

Andrew Stacey — Sat, 01 May 2010 11:21:42 -0700

Markdown and whatever can be integrated properly so that each knows about the other. The thing is that they need to act together, not one after the other. The n(Lab,Forum) system seems to work quite well with this, I certainly don't know of any cases of the two syntaxes getting confused. Actually, it is also possible to do them one after the other, but a little bit of trickery is needed first (the nForum uses both systems, depending on which formatter you use).

Harry Gindi comments on "What benefit do we get from using markdown?" (5287)

Harry Gindi — Sat, 01 May 2010 09:24:20 -0700

I would prefer if all of the markdown features aside from the way it handles lists and headings were removed. I will still write _blah_ for underlines, but now instead of italicizing it, it'll look the way it should (like it does in an e-mail).

Harald Hanche-Olsen comments on "What benefit do we get from using markdown?" (5286)

Harald Hanche-Olsen — Sat, 01 May 2010 08:51:40 -0700

Once the decision to use markdown has been made, I think it's better to stick with it. Having a gazillion incompatible dialects of markdown would be a pain in the posterior. That said, it would be nice if it were possible to tell markdown about the magical aspects of dollar signs, so it would refrain from doing its thing within TeX code. (You might object that markdown with magical dollar signs is just another markdown dialect, but this difference is at least much easier to explain to mathematicians.)

Scott Morrison comments on "What benefit do we get from using markdown?" (5285)

Scott Morrison — Sat, 01 May 2010 08:43:09 -0700

One problem would be backwards compatibility: we'd need to come up with an algorithmic way to edit all the old posts, and then presumably cooperation from Fog Creek to actually apply those edits to the database without having to actually edit through the web interface.

Peter McNamara comments on "What benefit do we get from using markdown?" (5284)

Peter McNamara — Sat, 01 May 2010 08:17:20 -0700

There may well be a positive answer to the question that forms the title of this post. As a user of mathoverflow, I don't know what it is though. My primary experience with the markdown is seeing peoples posts where there has been obvious struggles to fight the incompatabilities between markdown and latex. This seems most prominent with the use of the characters * and _.

I do not see the point of allowing the use of these symbols in markdown, and wish that we could disable them so that they don't interfere with our latex. As far as I can tell, their behaviour in markdown doesn't actually contribute anything new, since one can recreate the same effects using html. Thus, if we could drop these symbols from markdown, we wouldn't lose any capabilities that we already have. This is my 'feature request'.