insert text in rule

Question

I have difficulty writing a compact command that allows me to insert a text between two lines. I read some links such as this and this, but each one treats the left and right line separately

\documentclass{article}
\usepackage{amsmath} %<<=== 
\usepackage[normalem]{ulem}
\usepackage{xcolor}

\newcommand\gsout{\bgroup\markoverwith{\textcolor{gray}{\rule[0.5ex]{2pt}{2.5pt}}}\ULon}

\newcommand*{\sxrule}[1][3em]{\textcolor{gray}{\rule[0.5ex]{#1}{2.5pt}}\;}


\begin{document}

\sxrule Osservazioni \gsout{\hfill}

\end{document} 

Have any suggestions? thanks

Answer 1

Perhaps something like this:

Here's the code:

\documentclass{article}
\usepackage{xcolor}
\usepackage{lipsum}

\newlength\sxrulelength
\newcommand\sxrule[2][3em]{%
  \settowidth\sxrulelength{\,#2\,}%
  \noindent%
  \textcolor{gray}{\rule[0.5ex]{#1}{2.5pt}}\,#2\,%
  \textcolor{gray}{\rule[0.5ex]{\dimexpr\linewidth-\sxrulelength-#1\relax}{2.5pt}}%
}

\begin{document}

  \lipsum

  \sxrule{Osservazioni}

  \lipsum

\end{document}

The \sxrule macro has an optional argument that controls the length of the "left hand" line. As in the OP, this defaults to 3em.

Judging from the comments, perhaps the definition

\newcommand\sxrule[2][3em]{%
  \settowidth\sxrulelength{\,#2\,}%
  \noindent%
  \textcolor{gray}{\rule[0.5ex]{#1}{2.5pt}}\,\textbf{#2}\,%
  \textcolor{gray}{\rule[0.5ex]{\dimexpr\linewidth-\sxrulelength-#1\relax}{2.5pt}}%
}

is better as now \sxrule{Osservazioni} puts "Osservazioni" in bold:

Answer 2

\documentclass{article}
\usepackage[normalem]{ulem}
\usepackage{xcolor,lipsum}
\newcommand\filrule{{\color{gray}{\leaders
\hrule height .7ex depth -.4ex  \hfill }\hskip .0em}}
\def\ruledworld#1{\bigskip\noindent\filrule\quad%
#1\quad\filrule\bigskip\par}
\begin{document}
\ruledworld{Osservazioni}
\lipsum[2]
\ruledworld{Grandi conclusioni}
\lipsum[3]
\end{document} 

If you do not want the word centered but start at a fixed point, change the first \filrule in the definition of \ruledworld by a normal \rule. Or You can left a single \filrule on the left, but a few on the right (e.g., \filrule\filrule\filrule) to have the word centered with respect some point (at the 25% of the line, in that example).