101 reputation
3
bio website users.aims.ac.za/~bruno
location France
age 24
visits member for 2 years, 6 months
seen Aug 27 at 9:54

I've been using LaTeX more and more in the past nine years, initially typesetting solutions to maths problems, later taking notes in class for more than a year.

A few months back I had some ideas about writing a package. I was (un?)fortunate enough to find a copy of the TeXbook in my school's library. Since then, I have been hooked by the strange style of programming that TeX macros provide.

This has led me to become a member of the LaTeX3 team in May 2011. This was an exciting time to join the project: the team improved consistency of the expl3 language provided by l3kernel considerably, and we have seen people starting to code in the language. I have focussed in making the l3kernel code as fast and bullet-proof as possible (two often conflicting aims).

Current LaTeX projects:

  • Get l3fp to reach full IEEE-754 (2008) compliance. This module, which I am quite proud of, lets us parse expandably floating point expressions, in a way similar to eTeX's \the\numexpr...\relax for integers. The main missing parts are signalling NaNs and subnormal numbers, as well as providing functions to control the rounding mode.

  • Enrich l3fp with more functions, such as atan.

  • Clean up l3regex, the LaTeX3 regular expression engine, marking it as stable. In particular, add functions to act on a file, sed-like.

  • Write a PEG parser operating on strings. This could in principle be done expandably, but I am not yet sure whether it is necessarily useful.

  • Write a C compiler (this is not for LaTeX3, mostly to learn how compilers work). Having a full C-to-TeX compiler would immediately provide access to many other languages from TeX, since many compilers are written in C. Of course, the code would run rather slowly, and much slower than using LuaTeX.

  • Enable TeX to produce text output instead of pdf. This could be done either by using LuaTeX, or by modifying an engine, or by emulating TeX within TeX (which I have partly done).

  • Help with debugging macros either by providing a graphical interface to visualize expansion, or (easier, and partly done) by performing steps of expansion or assignments one by one and showing partial results with \typeout within TeX.

  • Understand how to best generalize LaTeX3's \tl_expandable_lowercase:n to do more general token-list transformations expandably. This might combine with the idea of a parser.

  • Perform partial macro expansion in a file, which would distinguish between user-defined macros and macros defined in a package.

  • Write an os-independent Makefile-like Lua program.

  • A few dormant packages, including the one that brought me to the TeX path two years ago.


May
17
comment Fermat Last Theorem for non Integer Exponents
You can generalise this to show that the set of real n for which there exist integers $x, y, z$ with $x^n + y^n = z^n$ is dense in $[0,\infty)$.
Nov
17
awarded  Student
Oct
22
comment How does $\sqrt{|e^{-y}\cos x + ie^{-y}\sin x|}= e^{-y}$
As it currently is, the question is wrong, so your answer is at best incomplete. $\sqrt{|e^{-y}\times ...|} = e^{-y/2}$, not $e^{-y}$.
Aug
1
comment Are there any synonyms of “pair of pants” in topology?
I have also heard (and used) trinion, in some conformal field theory papers (we often manipulate Riemann surfaces in 2d CFT).
Aug
1
comment Are non-circular manholes possible?
@J.M. You're right. However, the example of a spiral shows that Hans' question does have answers other than convex constant-diameter domains.
Aug
1
comment Are non-circular manholes possible?
Hans-Peter, a spiral cover to a spiral hole would not pass through I think: doing what J.M. describes would get the spiral stuck after one turn, since the spiral would bang into the ground from below. Actually your way of stating the problem with an infinite plane is a bit odd, since that means that the ground is entirely hollow. A slightly different (but more realistic) situation is if the hole below ground level is $\mathbb{R}^+ \times \text{shape}$ where the shape is part of $\mathbb{R}^2$.
Aug
1
comment Are non-circular manholes possible?
@J.M. I isn't clear: doing it in the naive way would get the cover will stuck when you try to pass the straight part through the hole.
Jul
30
comment Is there a simple explanation why degree 5 polynomials (and up) are unsolvable?
@ErickWong My bad. You are right, let me retract my comment. Perhaps 'if it were possible to "invert" the polynomial $x^5−x$ (i.e. solve $x^5-x=c$ directly like we can $x^5=c$)' would be better?
Jul
29
comment Is there a simple explanation why degree 5 polynomials (and up) are unsolvable?
Can't be $x^5-x$ since that has trivially $0$, $1$, $i$, $-1$ and $-i$ as solutions.
Feb
7
awarded  Supporter
Feb
7
awarded  Autobiographer