TeX, LaTeX and Friends

6:17 AM

@Manuel Can you point me to the comment? Basically \scantokens has some 'issues'

@Manuel Note that you need the \noexpand (or one of a few other possible tricks) in an \edef context, not if the \scantokens is used inline. The latter case is handled using a character with two different catcodes for 'cleanup'

@Manuel Ah, found the comment: that's not the case where you need \noexpand

Manuel

@JosephWright @egreg Okey, I really don't know what was going on, just was making sure. So still, the \noexpand is indeed needed when inside an \edef (if one chooses that trick instead of others)? Or does it work in \edef with \relax (for instance).

Manuel

6:37 AM

Okey, I see that the question I linked is precisely the explanation of these things :)

In any case, could anyone explain why and what happens what wipet's says? What exactly is \noexpand doing wrong there (that “ignores” the \endlinechar and works on \iftrue) that \relax solves? (I think I've intuition about what happens, but to see it explained in a line or two :D).

My intuition is as if I literally had a file with \noexpand on one line and \iftrue in the next, obviously, because the first line ends with a control sequence, there's no “space” (the same way there's no need for % at the end of that line), and the result is \noexpand\iftrue which leads to an error. In that case, any control sequence at the end of such line would be enough to not need %, hence using \relax.

In case that's true, why is it different inside \edef?

Joseph Wright

7:13 AM

@Manuel I'll look over this later: \relax certainly doesn't work inside \edef as TeX tries to expand a forbidden token

\edef\test{\scantokens{foo\relax}}

->foo\relax
! File ended while scanning definition of \test.
<inserted text>
                }
l.1 \edef\test{\scantokens{foo\relax}
                                     }

@Manuel As I said, \scantokens is not really properly set up but it is what it is: LuaTeX's \scantextokens is probably what was meant

Manuel

8:32 AM

@JosephWright Okey, it's not urgent, so no hurry, I'm just curious. Also, after playing a little bit this also doesn't work \detokenize\expandafter{\scantokens{foo}} and i don't understand it. If yo could point to a reference about \scantokens it would be great. I imagine \scantextokens a primitive in LuaTeX? And it can be used \scantextokens{whatever} and \edef\q{\scantextokens{whatever}} and it works as expected?

Joseph Wright

9:43 AM

@Manuel The formal reference for \scantokens is the e-TeX manual but it's not really clear on these issues. Essentially the knowledge about the problems of \scantokens comes from experiences. As you say, \scantextokens is a LuaTeX primitive

Paulo Cereda

10:42 AM

Quack!

Single Fighter

11:09 AM

the following does not compile.

\documentclass{standalone}
\begin{document}
\begin{enumerate}
\item foo
\end{enumerate}
\end{document}

a bug?

Paulo Cereda

6

Q: Can we use enumerate with standalone class?

Can we use \enumerate with \standalone class? Isn't enumerate basic LaTeX? The minimal example, which does not compile with standalone but it does with article, is: \documentclass{standalone} \usepackage{tikz} \begin{document} \begin{enumerate} \item test ...