Indent entire item block in enumerate

Question

I have the following MWE:

\documentclass{article}
\usepackage{lipsum}

\begin{document}   
\newenvironment{tight_enumerate}{
\begin{enumerate}
  \setlength{\itemindent}{-1.5em}
  \setlength{\itemsep}{1pt}
  \setlength{\parskip}{0pt}
}{\end{enumerate}}

\subsubsection*{Minimum Working Example}
\begin{tight_enumerate}
\item \lipsum[1]
\item \lipsum[2]
\item \lipsum[3]
\end{tight_enumerate}

\end{document}

which gives me the following:

As you can see, I have tried to indent(move to the left each item). However, only the first line of the item gets indented, while the remaining lines stay in place. I am wondering how to move the entire block in the item to the left.

Thanks for your help.

Answer 1

Dealing with the innards of LaTeX's list-like environments can be, to put it politely, a baffling experience. Therefore, rather than keep fiddling with the low-level parameters of a list environment directly, I'd recommend you employ the enumitem package and use its left=0pt and noitemsep options.

If this "look" is needed for just one enumerated list, you could provide these options as optional arguments to \begin{enumerate}. If it's needed several times, you could use the machinery of the enumitem package -- specifically, its \newlist and \setlist macros -- to create a new, bespoke enumerate-like environment that executes these options automatically. Both possibilies are explored in the following MWE.

\documentclass{article}
\usepackage{lipsum}     % filler text
\usepackage{showframe}  % draw rectangle around textblock
\usepackage{enumitem}   % for \newlist and \setlist macros
\newlist{tightenum}{enumerate}{1}
\setlist[tightenum]{label=\arabic*., left=0pt, noitemsep}

\begin{document}   

\begin{enumerate}[left=0pt, noitemsep]
\item \lipsum[2]
\item \lipsum[2]
\end{enumerate}
\hrule  % draw a full-width horizontal line
\begin{tightenum}
\item \lipsum[2]
\item \lipsum[2]
\end{tightenum}

\end{document}