preamble.sty

\usepackage[utf8]{inputenc}
\usepackage[a4paper,top=2cm,bottom=2cm]{geometry}
\usepackage{parskip}
\usepackage{hyperref}
\usepackage{enumitem}
\usepackage{listings}
\lstset{%
  basicstyle=\small\ttfamily,
  language=[LaTeX]{TeX},
  commentstyle=\small\ttfamily
}

% \usepackage{graphicx}
% \usepackage{lcg}
% \usepackage{xargs}
% \usepackage{float}

% Use \listinline in item description. 
% Answer by Martin Scharrer, taken from
% https://tex.stackexchange.com/questions/93944/using-lstinline-inside-a-item
\makeatletter
\let\orig@item\item

\def\item{%
    \@ifnextchar{[}%
        {\lstinline@item}%
        {\orig@item}%
}

\begingroup
\catcode`\]=\active
\gdef\lstinline@item[{%
    \setbox0\hbox\bgroup
        \catcode`\]=\active
        \let]\lstinline@item@end
}
\endgroup

\def\lstinline@item@end{%
    \egroup
    \orig@item[\usebox0]%
}

\makeatother