Macro to generate ordinal words from numbers?

Question

Is there a macro available that will turn "1" into "first", "2" into "second", etc. Let's call this macro "wordth". Then, for example, if item number 2 in an enumerate environment is labeled by \label{item:blah}, I could write something like

The \wordth{\ref{item:blah}} item is problematic.

which would be formatted as "The second item is problematic."

(Bonus points for other languages, but I only need it for English.)

This answer points to the nth package for turning "1" into "1st", etc. The engord package also does this. Neither appears to provide fully spelled out English ordinals. In many situations only full words for ordinals, not their abbreviations, are appropriate.

This is probably a FAQ, but it's one of those things that's difficult to search. Feel free to point to a dupe question and close.

Answer 1

You can use a combination of fmtcount (for writing the ordinal form of a counter) and refcount for extracting the number associated with a reference:

\documentclass{article}
\usepackage{refcount, fmtcount}

\newcommand*{\wordth}[1]{% \wordth{<reference>}
  \ordinalstringnum{\getrefnumber{#1}}}%

\begin{document}

\begin{enumerate}
  \item\label{enum:first} First item.
  \item\label{enum:second} Second item.
  \item Last item.
\end{enumerate}

See the \wordth{enum:second} item above, or item number~\ref{enum:first}.

\end{document}

Since you are using the \label-\ref system, you need to compile at least twice on the first go in order to work with settled references.

Note that \wordth{<reference>} requires a reference to some label. If you wish to reference hierarchical numbering schemes (like a subsection that is numbered 1.1) you're going to run into trouble. However, one could use zref's magic to circumvent this. It would require a little more muscle to work, including a possible interface change.

Answer 2

If this is the only way you intend to reference the item, you could incorporate \ordinalstring into \theenumi. (I'm assuming this is just for use in an enumerate environment.) For example:

\documentclass{article}

\usepackage{fmtcount}

\renewcommand{\labelenumi}{\arabic{enumi}.}
\renewcommand{\theenumi}{\ordinalstring{enumi}}

\begin{document}

\begin{enumerate}
\item First item.
\item\label{item:blah} Second item.
\item Third item.
\end{enumerate}

The \ref{item:blah} item is problematic.

\end{document}

Alternatively, scoping the change so it only affects this particular enumerate environment:

\documentclass{article}

\usepackage{fmtcount}

\begin{document}

\begin{enumerate}
\renewcommand{\labelenumi}{\arabic{enumi}.}
\renewcommand{\theenumi}{\ordinalstring{enumi}}
\item First item.
\item\label{item:blah} Second item.
\item Third item.
\end{enumerate}

The \ref{item:blah} item is problematic.

\end{document}

Both produce: