#enumeratelists
Possible Duplicate:
Enumerate with Properties
How can I create a list with a mixed listing, i.e. made of a fixed prefix (e.g. a letter) and an auto incremented number. E.g.
A1 my text....
A2 another text;
A3 again text.
Maybe exists such a package that I don't know…
Personally I don't like this kind of repetition, although it is used by some. I think it's preferable to repeat the example with a new number. But independent of this opinion, the effect is easily achieved with both the gb4e package and the linguex package.
gb4e
It provides an \exr{<label>} command, which formats the example based on reference to a label.
\documentclass{article}
\usepackage{gb4e}
\newcommand\extwo{Example 2}
\begin{document}
\begin{exe}
\ex Example 1
\ex \extwo \label{ex2}
\end{exe}
Text
\begin{exe}
\ex Example 3
\end{exe}
Text
\begin{exe}
\exr{ex2} \extwo% Example 2 repeated with its original number, i.e. "1."
\end{exe}
Text
\begin{exe}
\item Example 4% Is listed as "3." when I want it be listed as "4."
\end{exe}
\end{document}
linguex
It allows its \ex. command to have an following optional argument to set the label. This argument can contain a \ref{} command.
\documentclass{article}
\usepackage{linguex}
\newcommand\extwo{Example 2}
\begin{document}
\ex. Example 1
\ex. \extwo \label{ex2}
Text.
\ex. Example 3
Text.
\ex.[\ref{ex2}] \extwo
Text
\ex. Example 4
\end{document}
\documentclass{article}
\usepackage{enumitem}
\def\threedigits#1{%
\ifnum#1<100 0\fi
\ifnum#1<10 0\fi
\number#1}
\begin{document}
\begin{enumerate}[label={\textbf{REG/\protect\threedigits{\theenumi}}},leftmargin=*]
\item content
\item content
\item content
\end{enumerate}
\end{document}
Best Answer
Use
enumitem.