Enumerate with alpha counters like 'aa', 'ab' etc

Question

When having a list like:

\documentclass[twoside]{book}
\RequirePackage{enumitem}
\begin{document}
\begin{enumerate}[label=\alph*,start=25]
\item an item
\item an item
\item an item
\item an item
\item an item
\item an item
\item an item
\item an item
\end{enumerate}
\end{document}

we get the error:

! LaTeX Error: Counter too large.
See the LaTeX manual or LaTeX Companion for explanation.
Type  H <return>  for immediate help.
 ...
l.23 \item a
            n item

due to the fact that the counter exceeds 26.

When having e.g. HTML the numbering would be like: y, z, aa, ab, ac, ad or at least wrap around back to a?

Does something like this exist in LaTeX as well?

The relevant duplicate is Numbering exceeding the 26 letter alphabet — Alan Munn, Apr 28 '21 at 18:04

score 4 · Accepted Answer · answered Apr 28 '21 at 18:13

4

Adapting one of the answers from here: Counter too large error with \item

\documentclass[twoside]{book}
\RequirePackage{enumitem,alphalph}
\makeatletter
\newcommand{\AlphAlphFmt}[1]{@alphfmt{#1}}  % Define the \alphalph wrapper for enumitem 
\newcommand{@alphfmt}[1]{\alphalph{\value{#1}}}  % Internal representation 
\AddEnumerateCounter{\alphalphFmt}{@alphfmt}{aaa} % Register this new format
\makeatother
\begin{document}
\begin{enumerate}[label={(\AlphAlphFmt*)},start=25]
\item an item
\item an item
\item an item
\item an item
\item an item
\item an item
\item an item
\item an item
\end{enumerate}
\end{document}

answered Apr 28 '21 at 18:13

Steven B. Segletes

237,551

Unrelated, but I'm curious: is there a reason for using \RequirePackage rather than \usepackage? – chsk Apr 28 '21 at 18:16
@chsk I just followed from the question of the OP. However, if you are interested, https://tex.stackexchange.com/questions/19919/whats-the-difference-between-requirepackage-and-usepackage – Steven B. Segletes Apr 28 '21 at 18:18
The reason I used \RequirePackage is that I cut and pasted it from a sty file. – albert Apr 28 '21 at 18:23
@StevenB.Segletes thanks, good to know! – chsk Apr 28 '21 at 19:12
Since we may need the equivalent in capital letters, I would suggest a slight modification in order to keep on with the difference between \alphalphFmt and \AlphAlphFmt : \makeatletter \newcommand{\alphalphFmt}[1]{@alphfmt{#1}} % Define the \alphalph wrapper for enumitem \newcommand{@alphfmt}[1]{\alphalph{\value{#1}}} % Internal representation \AddEnumerateCounter{\alphalphFmt}{@alphfmt}{aaa} % Register this new format \makeatother – user1771398 Feb 18 '24 at 08:09

Enumerate with alpha counters like 'aa', 'ab' etc

1 Answers1