tweaklist.sty

%% start of file `tweaklist.sty'.
%% Original by Jakob Schiøtz, downloaded from http://dcwww.camd.dtu.dk/~schiotz/comp/LatexTips/tweaklist.sty; not found on ctan.
%% Modified by Xavier Danaux (xdanaux@gmail.com).
%
% The tweaklist.sty package redefines the itemize, enumerate and description packages, so that all parameters can be adjusted.
% This was done by copying the original definitions, and adding "hook commands" that are executed when entering the environment.
% The hook commands are initially empty, but can be redefined with \renewcommand.
%
% This work may be distributed and/or modified under the
% conditions of the LaTeX Project Public License version 1.3c,
% available at http://www.latex-project.org/lppl/.


% hooks for the itemize environment
\def\itemhook{}
\def\itemhooki{}
\def\itemhookii{}
\def\itemhookiii{}
\def\itemhookiv{}
% hooks for the enumerate environment
\def\enumhook{}
\def\enumhooki{}
\def\enumhookii{}
\def\enumhookiii{}
\def\enumhookiv{}
% hook for the description environment
\def\deschook{}
% original environment definitions, with hooks added
\def\enumerate{%
  \ifnum \@enumdepth >\thr@@\@toodeep\else
    \advance\@enumdepth\@ne
    \edef\@enumctr{enum\romannumeral\the\@enumdepth}%
      \expandafter
      \list
        \csname label\@enumctr\endcsname
        {%
          \enumhook \csname enumhook\romannumeral\the\@enumdepth\endcsname%
          \usecounter\@enumctr\def\makelabel##1{\hss\llap{##1}}%
        }%
  \fi}
\def\itemize{%
  \ifnum \@itemdepth >\thr@@\@toodeep\else
    \advance\@itemdepth\@ne
    \edef\@itemitem{labelitem\romannumeral\the\@itemdepth}%
    \expandafter
    \list
      \csname\@itemitem\endcsname
      {%
        \itemhook \csname itemhook\romannumeral\the\@itemdepth\endcsname%
        \def\makelabel##1{\hss\llap{##1}}%
      }%
  \fi}
\newenvironment{description}
  {\list{}{\deschook\labelwidth\z@ \itemindent-\leftmargin
           \let\makelabel\descriptionlabel}}
  {\endlist}