"Overfull \hbox" problem

Question

I have an overflow problem but I can`t figure out how to solve it. Why is

\rule{\textwidth}{0.6pt}\\[\baselineskip]   
\vspace{0.5cm}

giving out an overfull error if the text is not responsible?

Answer 1

I can replicate the OP's issue precisely with the following test code:

\documentclass[12pt]{article}

\begin{document}

\rule{\textwidth}{0.6pt}

\end{document}

Spefically, I get the following warning message:

Overfull \hbox (17.62482pt too wide) in paragraph at lines 5--6

Observe that Overfull \hbox (17.62482pt too wide) also shows up in the warning message reported by the OP.

The fix? I suggest issuing the instruction \noindent immediately before the \rule instruction.

A final comment: It doesn't have to be text that causes the overfull-hbox warning; it can just as well be a horizontal rule.

Answer 2

The overfull is caused by the paragraph indentation. Thus \rule should be preceded by \noindent.

But, as you're doing flushleft things just after that rule, just place the rule inside it.

Also \\[\baselineskip]\vspace{0.5cm} is not very good programming and \\ shouldn't be used in that context anyway: just use a blank line after the rule followed by the desired amount of vertical space.

Adding columns in the tabular to get space isn't the best way too: look at the code below where a specific distance between columns is inserted.

\documentclass[a4paper]{book}

\newcommand{\printauthor}{A. Uthor}
\newcommand{\matnr}{176--761}
\newcommand{\abgabedatum}{July 38, 2043}


\begin{document}

\begin{flushleft}

\rule{\textwidth}{0.4pt}

\vspace{1cm}

\begin{tabular}{@{} l @{\hspace{2em}} l @{}}
\textbf{von:}         & \printauthor \\
                      & Matrikelnummer: \matnr \\
\textbf{Betreuer:}    & Dr.\ Daniel Brunner \\
\textbf{Abgabedatum:} & \abgabedatum
\end{tabular}

\end{flushleft}

\end{document}

Adjust the lengths to your liking.