How can I improve my "hands-on"/ "working" knowledge of TeX's low/middle/high/higher -level control sequences?

Question

I am not an experienced TeX/LaTeX user. I know just about enough to write my thesis. As my interest grows, I'd like to continue improving on my TeX/LaTeX knowledge, more specifically, my "working" knowledge!

On TeX.SX, whenever I see an answer that includes TeX's control sequences, I immediately take a step back! .. and I have been using this community as a knowledge resource for more than 3 years now!

Sometimes I find answers containing TeX's control sequences that let me do exactly what I need to do, but I use them on a blind belief that -

"these guys are pros, they know what they are talking about!"

.. because, I simply don't know enough about TeX's low/middle/high/higher -level control sequences to understand what they've done in their solution.

For instance, I posted a question earlier, to which I got this solution. Many thanks to the person who answered; however, my first impression of it was -

"darn! it contains lot's of pure TeX stuff, so it must be a better solution that what I came up with!"

This experience has made me realise that I need to expand my "working" knowledge about the TeX/LaTeX low/middle/high/higher -level control sequences, if I am ever going to understand what some of these more experienced users are talking about.

So, here's my question again:

How can I improve my "hands-on"/ "working" knowledge of TeX's low/middle/high/higher -level control sequences; so that one day, if required, even I'd be able to use some of these useful TeX/LaTeX tools?

Many thanks in advance!

Answer 1

My first source is TeX.SX! I learned here so much about TeX/LaTeX and macro expansion and still feel sometimes a little uneducated, but it's improving ;-)

However, if there is no precise question (title) on what one is looking for, some manuals are perhaps the better choice.

My main printed source is the TeX by Topic book by Victor Eijkhout, but it's some inspiration on TeX for deeper insights.

(No, I don't own a copy of the TeX Book, I admit it here.)

The principles of TeX can be classified in some categories (as I learned here basically during the last 16 months)

• The \def, \edef, gdef and \xdef statements for defining macros

• the notorious \expandafter (or bunch of \expandafters ;-))

• command sequences itself and constructing them on the fly using \csname foo \endcsname

• Conditionals such as \if...\else...\fi

• Registers such as allocated with \newcount, \newdim etc.

• Low - level file access with file handles generated by \newread and \newwrite as well as \openin, \openout, \closein and \closeout.

Knowing the basic syntax and the principles behind those commands/concepts will provide some clue.

But the most important thing (in my point of view) is practising using problems!

For LaTeX specific issues there are sources on the net as well as the LaTeX Companion or the very topic - related books by Herbert Voss, however, some of them were published in German language only (so far)

Answer 2

From my experience as an end usr, and not a pro developer, I would say you are on the right track: first, find a need (something you need), and then try to write a package to solve that need. In the process check reliable documentation (I often perused source2e.pdf and the source code of the base LaTeX classes.pdf, all available at the base directory of CTAN, and documentation for the basic tool packages of the system, which are pretty good examples of TeX programming and have lots of clever hacks specific to LaTeX; then check Abrahams, Berry, and Hargreaves's TeX for the Impatient, which is pretty to the point, as often as you need it while reading the source code, to figure out things about TeX's kernel primitives; and perhaps also read the documentation for your favorite engine -mltex, etex, pdftex- to see the particulars of their implementation). Finally, ask relevant forums (comp.text.tex is less stressful than SE, imnsho). Hacking is like poetry: first you sing others' songs; then you copy a lot; finally, you may start to sing on your own.