latex tabular issue

Question

I am creating a tabular in LaTeX.

I want one column to be as small as possible, with no inter column spacing, so that it's just enough to fit the text. I know the answer to this question: I need to use @{}c@{}.

I also want to be able to have a linebreak wherever I want in my cell. I also know the answer to this question: I need to use a tabular within my tabular.

The problem is that I can't manage to make these two solutions work together: when I try to have 2 lines within a cell, the column gets expanded beyond the size of the text.

Here is such an example:

\begin{small}
        \begin{tabular}{|@{}c@{}|}
            A\\B\\C\\   
        \end{tabular}
\end{small}

Compare with (in the following code, there is unwanted extra space) :

\begin{tabular}{|@{}c@{}|}
\begin{small}
        \begin{tabular}{@{}c@{}}
            A\\B\\C\\   
        \end{tabular}
\end{small}
\end{tabular}

Answer 1

In your code, there are two spurious blank spaces: one, after \begin{small}, and the second one, after the inner \end{tabular}; you can remove those spaces using % at the end of the line. Compare the result obtained in the following example showing your code and a version with the spaces removed:

\documentclass{article}

\begin{document}

\noindent Undesired blank spaces:
\begin{tabular}{|@{}c@{}|}
\begin{small}
        \begin{tabular}{@{}c@{}}
            A\\B\\C\\   
        \end{tabular}
\end{small}
\end{tabular}

\noindent Spurious spaces removed: 
\begin{tabular}{|@{}c@{}|}
\begin{small}%
        \begin{tabular}{@{}c@{}}
            A\\B\\C\\   
        \end{tabular}%
\end{small}
\end{tabular}

\end{document}

\small is a switch not an environment; use this:

\begin{tabular}{|@{}c@{}|}
  \small
  \begin{tabular}{@{}c@{}}
   A\\B\\C\\   
   \end{tabular}
\end{tabular}

With this input, spurious spaces don't show up because tabular ignores white space at the start and end of cells (and the endline after \small is ignored because it's a command name).

When nesting tabulars normally is convenient to enclose the inner one using braces; in this case, however it's not necessary since the inner tabular only has one column.

Answer 2

The following works for me:

\documentclass{article}
\begin{document}
\begin{tabular}{cl}
  \small
  \begin{tabular}{|@{}c@{}|}
    A\\B\\C
  \end{tabular}&
  Some more text
\end{tabular}
\end{document}

Note that the vertical rules is placed in the innermost tabular where you use your line breaks. You could also consider the makecell package which does something similar. Here's a short example that produces similar output:

\documentclass{article}
\usepackage{makecell}% http://ctan.org/pkg/makecell
\begin{document}
\begin{tabular}{|@{}c@{}|l}
  \small
  \makecell{A\\B\\C}&
  Some more text
\end{tabular}
\end{document}