8
votes
1answer
213 views

Expandable, standard TeX only way to compare balanced token lists

Is there a (reasonably) efficient macro that does something similar to \long\def\comparets#1#2{\def\aa{#1}\def\bb{#2}\ifx\aa\bb true\else false\fi} except is expandable (i.e. ...
11
votes
1answer
428 views

Using \toks registers

I was reading this tutorial for TeX programming: http://pgfplots.sourceforge.net/TeX-programming-notes.pdf recommended in the 2-nd answer here: Where do I start LaTeX programming? It says: ...
41
votes
3answers
851 views

What is a token?

Please forgive such a basic question, but I did some Google searching and looked around on this site, and while there are many threads and online resources that involve tokens, I can't seem to find a ...
4
votes
3answers
231 views

How are space tokens and empty lines processed by long commands (as their potential arguments)?

How are spaces and empty lines processed by long commands (i.e., those that do not accept paragraph breaks inside)? Are there different space tokens aside from " " and an empty line? It appears that ...
19
votes
5answers
1k views

How does one append material to a token list?

Several times, the floatrow package uses \newtoks which (according to this website) means that a token register is allocated. An example code snippet is ...
5
votes
1answer
343 views

Removing and storing the head of a token list/\toks

I am given a token list (parameter-less macro) \myTokenList, defined, e.g. by \def\myTokenList{$(x + y)^2$, \ie, \(x^2+y^2+2xy\)} and I want to split it as the first token, and the rest, obtaining ...
9
votes
3answers
382 views

Making register declarations local, Undefining a register (count, toks, etc.)

Is it possible to make \newcount, \newtoks, etc. respect grouping, so that, e.g., \newcount\temp\temp=2{\newcount\temp\temp=1}\showthe\temp gives 2 (instead of 0)? Relatedly, is it possible to ...
27
votes
6answers
4k views

Test whether token list is empty

Is it possible to test whether a token list register is empty without expanding it?