I need information about § character. I have seen it used for numbering (equivalent to nº) and as a separator. Which is its name or code? Where can it be used?
[Tex/LaTex] The § character
symbolsunicode
Related Solutions
listings doesn't really have UTF-8 support, so what happens when it finds → is essentially random.
You need not to declare the character if you load textcomp, because LaTeX knows how to translate it to \textrightarrow, but you need to teach it explicitly to listings.
\documentclass[a4paper]{article}
\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage[ngerman]{babel}
\usepackage{textcomp}
\usepackage{listings}
\lstset{
literate={→}{\textrightarrow}1
}
\begin{document}
foo → bar
\begin{lstlisting}
foo → bar
\end{lstlisting}
\end{document}
Abstractly your description is more or less right. Classical TeX doesn't have any information about character shapes from the font. It just deals with font metrics where each character is four numbers (height, depth, width and italic correction), but while the overall model is often known as "boxes-and-glue" within TeX itself, characters form a separate node type, corresponding to horizontal or vertical lists (which as you note can be nested) and while characters and rules are somewhat box like they are not actually boxes.
So \setbox0=\hbox{a} saves a box with a horizontal list containing the character node for a. That character is not itself a box and you can't do \setbox0=a.
Best Answer
It is a section sign, you can typeset it with TeX/LaTeX by typing
\S.