Como posso fazer uma tabela de símbolos com TeX?

Question

Eu usei o seguinte comando:

\documentclass{article}
\usepackage{xypic}
\usepackage[final]{showexpl}
\begin{document}
 \begin{LTXexample}[pos=r,rframe=single,numbers=none,basicstyle=\ttfamily\small,]
\xymatrix{A \ar[r]^f & B}
\xymatrix{A \ar@{^{(}->}[r]^f & B}
\end{LTXexample}
\end{document}

Isso me dá

mas prefiro criar a seguinte tabela:

Answer 1

Você pode usar um tabularambiente simples:

\documentclass[]{article}

\usepackage[T1]{fontenc}
\usepackage{array}
\usepackage{xypic}

\begin{document}
\begin{center} 
\renewcommand\arraystretch{1.25}
\begin{tabular}{|p{.6\linewidth}|>{\centering\arraybackslash}p{.3\linewidth}|}
\hline
  \centering Objetive {\footnotesize and} Input \par\footnotesize Commands to produce the diagrams  displayed on the right are as follows, respectively: &
   Output\par\footnotesize\itshape (what you get) 
 \tabularnewline\hline
  {\small The default case arrow:}\par
    \verb+\xymatrix{A \ar[r]^f & B}+  & $\xymatrix{A \ar[r]^f & B}$
 \tabularnewline\hline
  {\small Inclusion arrow:}\par
    \verb+\xymatrix{A \ar@{^{(}->}[r]^f & B}+  & $\xymatrix{A \ar@{^{(}->}[r]^f & B}$
 \tabularnewline\hline
\end{tabular}
\end{center}
\end{document}

Answer 2

Isto evita a duplicação de código; você especifica o código na coluna da esquerda e diz \usecodena segunda coluna.

\documentclass[]{article}

\usepackage[T1]{fontenc}
\usepackage{array,booktabs,xparse}
\usepackage{xypic}

\NewDocumentCommand{\code}{v}{%
  \gdef\usecode{$\scantokens{#1}$}%
  \texttt{#1}}

\begin{document}

\begin{table}
\caption{Table of the main \Xy{} constructs}

\centering
\bigskip

\begin{tabular}{
  m{.6\columnwidth}
  >{\centering\arraybackslash} m{.3\columnwidth}
}
\toprule
\multicolumn{1}{p{.6\columnwidth}}{\centering
  Objective {\footnotesize and} Input \par
   \footnotesize Commands to produce the diagrams displayed
   on the right are as follows, respectively:} &
\multicolumn{1}{p{.3\columnwidth}}{\centering
  Output\par\footnotesize\itshape (what you get)} \\
\midrule

The default case arrow:\newline
  \code{\xymatrix{A \ar[r]^f & B}}  & \usecode \\
\midrule

Inclusion arrow:\newline
\code{\xymatrix{A \ar@{^{(}->}[r]^f & B}}  & \usecode \\
\bottomrule
\end{tabular}
\end{table}
\end{document}