Using \cref and custom labels for inference rule names

Question

I have an array environment that is used to present inference rules (via a custom command). Now, these inference rules have names and i would like to refer to them using \label and \cref commands. I am guessing this is possible though the details elude me.

As a small example, this is the command:

\newcommand{\typerule}[3]{\ensuremath{\begin{array}{c}\textit{\scriptsize ({#1})} \\#2 \\\hline{\ensuremath{#3}}\end{array}}}

It produces an inference rule with hypotheses (#2), a line, a conclusion (#3), all topped by a name for the rule (#1).

My idea would be to add another parameter and something \label-style related to it, so that in the text later on i can use cleveref's \cref{} and then the name saved in the environment (and the related category name) pop up.

So i would write

\typerule{name}{premise}{conclusion}{labelidentifier}

and somewhere else

The \cref{labelidentifier} does ...

and the produced output should be something like

The rule name does

where rule is generated by cleveref and name is the one i specified previously.

Answer 1

Trick cleveref into thinking that “name” is the number.

\documentclass{article}
\usepackage{array,booktabs,cleveref}

\newcounter{typerule}
%%% standard format
%\crefname{typerule}{rule}{rules}
%%% more complex form
\crefformat{typerule}{#2rule~\textit{#1}#3}
\Crefformat{typerule}{#2Rule~\textit{#1}#3}

\newcommand{\typerule}[4]{%
  \def\thetyperule{#1}%
  \refstepcounter{typerule}%
  \label{#4}%
  \begin{tabular}{c}
  \scriptsize (\textit{#1}) \\
  $#2$ \\
  \midrule
  $#3$
  \end{tabular}%
}

\begin{document}

\typerule{modus ponens}{A\to B\quad A}{B}{MP}

\bigskip

The \cref{MP} does something.

\end{document}

I've also changed somewhat your command, in order to remove the acrobatic parts with \ensuremath and adding a better spacing with \cmidrule.