5:12 AM
(re [this question](http://tex.stackexchange.com/questions/27825/why-does-a-defined-command-appear-differently-in-the-align-environment) ) Does somebody know why
{\catcode\,=\active \gdef,{\mbox{ok}}}
\def\macro{\begingroup \mathcode\,="8000\relax \macrox}
\def\macrox#1{#1\endgroup}

$\macro{,}$
works, while
{\catcode\,=\active \gdef,{\mbox{ok}}}
\def\macro{\begingroup \mathcode\,="8000\relax \expandafter\endgroup\macrox}
\def\macrox#1{#1}

$\macro{,}$
doesn't?

2 hours later…
7:04 AM
@AndreyVihrov \mathcode and \catcode are not quite the same as each other. With \catcode, your approach would work as TeX will tokenize #1 as ,_{13}. On the other hand, \mathcode is not 'attached' to tokenized input, so it's the \mathcode at point of typesetting that is important.

7:44 AM
TeX is hard :-)

3 hours later…
10:36 AM
@AndreyVihrov \def\macro{\begingroup\mathcode\,="8000 \macrox and \def\macrox#1{#1\endgroup} should work, because the \mathcode assignment is undone after the expansion of \macrox; but \def\macro#1{\begingroup\mathcode\,="8000 #1\endgroup} is simpler.
When TeX finds a \mathcode with value "8000 it looks for the definition of the character as if it were active; but the character token found must have category 11 or 12 in order that its \mathcode is looked at.

@egreg Indeed. The two macros were there because I occurred to think that mathcodes, like catcodes, are assigned when reading input.

1 hour later…
11:51 AM
Here's a bizarre error message ... though I doubt its veracity! Take a look at the linked screen shot in: tex.stackexchange.com/q/27852/86

@AndrewStacey Most likely some custom class file
@AndrewStacey Google proves me wrong, the line is generated by apacite (since when caps and triple exclamation marks are a good style?)

The problem with ctanupload is that I sometimes find bugs only after I uploaded its new version to CTAN (using itself of course). :-(
@AndreyVihrov I found it as well using google code :-) It is indeed unrelated. A message like this shouldn't be produced by default.

12:08 PM
@AndrewStacey Emergency stop is issued in \nonstopmode when a required file is not found.
Or not writable; it probably has to do with the fact that some TeX file has the strange name wto_version2.0.tex with a "double extension".

1 hour later…
1:34 PM
@AndreyVihrov It's probably APA style. :-) (Along with unnumbered sections and many other inanities.)

2:29 PM
0

I am using emacs on Ubuntu 10.10. I was trying to add doublespace.sty to my packages. To figure out what directory to put the doublespace.sty in I did a search on my computer for amsmath.sty, since I know that package works, and found the directory it was in, which was a subdirectory of /usr/s...

4 hours later…
6:25 PM
We are now down to 200 'unanswered' questions: someone has been working hard (@lockstep?)

7:21 PM
I've now cobbled together a nice highlighting facility for a beamer presentation, using the background canvas to actually draw the highlighter strokes.
Going to use it "live" in tomorrow's lecture ..

@AndrewStacey Cool, any preview for us?

7:39 PM
@PauloCereda Scroll down to the last lecture (2011-09-09) on mathsnotes.math.ntnu.no/mathsnotes/show/lecture+notes+2011 and look at the beamer version.

@AndrewStacey Awesome! They look very attractive to the eye. (a possible blog post?)

8:04 PM
Congrats to Jukka Suomela, first one to earn the Populist badge: tex.stackexchange.com/badges/39/populist
3

cool :)

8:19 PM
@JosephWright No -- this must have been a co-production of many users. I only wrote two or three "Please convert your comment into an answer" messages.

@lockstep Well, it's done the job :-)