REPLs in strange places: Lua, LaTeX, LPeg, LPegRex, TikZ

[Eduardo Ochs]

Hi list,

two weeks ago I gave a presentation at the EmacsConf2023. It was very
bad - the programs that I was planning to show weren't finished and I
didn't have the time to rehearse enough before recording the video, so
it ended being a very strange presentation - it ended up being about
_the design decisions behind some weird programs that no one could see
any use for_.

Now this is partially fixed. If you update eev to its latest version
then all these links should work:

  (find-1stclassvideo-links "eev2023repls")
  (find-eev2023replsvideo "00:00")
  (find-eev2023replslsubs "00:00")
  (find-show2-intro)
  (find-show2-intro "2. Installation (on Debian)")

  http://anggtwu.net/emacsconf2023.html
  http://anggtwu.net/eev-intros/find-show2-intro.html
  http://anggtwu.net/eev-intros/find-show2-intro.html#2
  http://www.youtube.com/watch?v=IDBQo_YYfA8

Here is a way to sell it. Lpeg is one of those tools that may look
otherworldly at first, but that makes sense gradually - we see a
presentation about it in the year Y, then in the years Y+1, Y+2, ...,
Y+5 we have some occasional thoughts like "hm, lpeg may be the right
tool for this", and then in the year Y+6 we try to learn it - and if
we do manage to learn it, then it becomes one of our favorite tools.

My presentation was about a way to make lpeg easy to learn. _At this
moment_ the instructions here

  (find-show2-intro "2. Installation (on Debian)")
  http://anggtwu.net/eev-intros/find-show2-intro.html#2

only cover the hard part: how to install everything from a big eepitch
block, in which in the first time we have to read each line before
<f8>-ing it - to understand what each line does!!! - but after that we
can re-execute everything by just <f8>-ing around thoughtlessly, and
we can save our attention for the other parts.

Note that _the lpeg tutorial isn't there yet_... (find-show2-intro)
has a few links like this one,

  (find-show2 "LUA/ParseTree2.lua" "ParseTree-tests")

that point to test blocks with demos that "should be impressive", but
I still need to prepare the test blocks with demos that "should be
easy to understand"... for example, the demos that will explain with
examples most of the constructions in these sections of the docs:

  http://www.inf.puc-rio.br/~roberto/lpeg/lpeg.html#introduction
  http://www.inf.puc-rio.br/~roberto/lpeg/re.html
  https://github.com/edubart/lpegrex#quick-references

Anyway, at this moment any feedback like "I'm using the distribution
Foo and line blah in the installation script doesn't work" or "I'm using
the distribution Blep and to make the line blah work on it I had to
change it in the ways such and such" would help me A LOT!

  Cheers, happy fun with weird Christmas tools,
    Eduardo =)