8
votes
1answer
61 views

weird ifnum with compact syntax [duplicate]

In some packages like tabularx, I find the following syntax in many places {\ifnum0=`}\fi or even \ifnum0=`{\fi} But I can't figure out why this can be useful for? Is ` a register of some kind? ...
13
votes
2answers
466 views

What is the difference between square brackets and curly brackets in a command invocation?

Pardon the naive beginner question. In a command like: \textcolor[HTML]{4C7045}{dark green text}, or \documentclass[12pt]{article}, or \begin{figure}[htb], why are some arguments surrounded by [] and ...
15
votes
2answers
436 views

Why does `x_\text y` work?

As far as I have understand the tokenization in LaTeX, x_\text y will be split up into x _ \text y Now the _ will consume/bind to the next token. However, \text takes an argument as well. If _ ...
23
votes
2answers
510 views

Backward definition of (La)TeX commands

Again and again I see, that TeXnicians define commands and do several things with them in the reverse order, I would do this as amateur. See this example: In his answer to scrpage2: Three ...
3
votes
1answer
208 views

Expanding subscript and subscript capabilities

Well, I liked the idea expressed in the question alternative syntax of subscripts using tex. But I want it to work in a sightly different way. I just want to expand the usual _ and ^. How? So that ...
4
votes
2answers
207 views

alternative syntax of subscripts using tex

I would like to sometimes write subscripts using different syntax, instead of $u_{xx} blahblah$ write something like $u⎵xx blah blah$, or even $u⎵xx+blah blah$ where either space following the x ...
15
votes
4answers
2k views

How to make a real backslash (escape) character?

I just want a good way to make a backslash character (or whatever character(s) any given format uses as escape characters), suitable to \write to a file or pass to a pdfTeX primitive. Let me ...