paultpearson
commented
5 years ago I also emailed this issue to Andrew offline. He responded that I "might be using an old version of the expl3 package. The command that is highlighted was introduced in 2018. Are you able to update your TeX installation?" He was correct. Updating from Texlive (default on Ubuntu 18.04) to Texlive 2019 fixed the problem.
For other people who might be in the same situation, here are the steps I used to update to Texlive 2019:
Try the following commands, one after another. If you progress, respective folders may already be deleted:
sudo apt-get purge texlive*
sudo rm -rf /usr/local/texlive/* and rm -rf ~/.texlive*
sudo rm -rf /usr/local/share/texmf
sudo rm -rf /var/lib/texmf
sudo rm -rf /etc/texmf
sudo apt-get remove tex-common --purge
rm -rf ~/.texlive
find -L /usr/local/bin/ -lname /usr/local/texlive/*/bin/* | xargs rm
This finds all the files in /usr/local/bin which point to a location within /usr/local/texlive/*/bin/* and removes them; because we’ve already deleted all of /usr/local/texlive, these are dead links. To see which files are being deleted, replace xargs rm with xargs -t rm (or tee off to a log file, or whatever).
Download
install-tl-unx.tar.gz
from
http://ftp.math.purdue.edu/mirrors/ctan.org/systems/texlive/Source/
unpack via tar -zxvf install-tl-unx.tar.gz and run sudo ./install-tl.
Add /usr/local/texlive/2019/texmf-dist/doc/man to MANPATH.
Add /usr/local/texlive/2019/texmf-dist/doc/info to INFOPATH.
Most importantly, add /usr/local/texlive/2019/bin/x86_64-linux
to your PATH for current and future sessions.
Logfile: /usr/local/texlive/2019/install-tl.log
Set the path for Texlive system wide:
https://stackoverflow.com/questions/37676849/where-is-path-variable-set-in-ubuntu
Edit the file /etc/environment
sudo nano /etc/environment
PATH="/usr/local/sbin: ...STUFF OMITTED HERE... :/usr/local/texlive/2019/bin/x86_64-linux"
MANPATH="/usr/local/texlive/2019/texmf-dist/doc/man"
INFOPATH="/usr/local/texlive/2019/texmf-dist/doc/info"
Finally, restart your computer so that the changes in /etc/environment are ready system wide.
Best regards, Paul
Hi Andrew!
I'm having problems getting your braids package to work for me. I have downloaded the package from CTAN
http://mirrors.ctan.org/graphics/pgf/contrib/braids.zip
unzipped it and entered the braids folder, run
pdflatex braids_code.textwice and thenpdflatex braids.texand I get the following error message! Undefined control sequence.