How to nest tables?

Question

I want to make a table inside another table as follows. Unfortunately, it does not work. What is wrong with it?

\documentclass{minimal}
\usepackage{array,longtable,calc}

\begin{document}

\begin{longtable}{*{2}{m{0.5\linewidth}}}
%
\begin{longtable}%
{*{2}{m{0.5\linewidth}}}
A & B\tabularnewline
C & D\tabularnewline
\end{longtable}%
                                        & E \tabularnewline
F                                 & G \tabularnewline
\end{longtable}


\end{document}

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EDIT 1

Based on @Herbert's suggestion to use tabular for the inner table, here is my modification. However, the rule does not appear. :-)

\documentclass{minimal}
\usepackage{array,longtable,calc}

\begin{document}

\begin{longtable}{|*{2}{m{0.5\linewidth}|}}
\hline%
\begin{tabular}%
{|*{2}{m{0.5\linewidth}|}}
\hline%
A & B\tabularnewline\hline
C & D\tabularnewline\hline
\end{tabular}%
                                        & E \tabularnewline\hline
F                                 & G \tabularnewline\hline
\end{longtable}


\end{document}

Answer 1

use not the minimal class, then there are no font informations for the lines. Hoiwever, you cannot use for all tables vertical lines, then they are overwritten and sometiomes with a gap.

\documentclass{article}
\usepackage{array,longtable,calc}

\begin{document}

\begin{longtable}{|@{}*{2}{m{0.5\linewidth}|}}\hline
\begin{tabular}{m{0.5\linewidth-\tabcolsep}|m{0.5\linewidth-\tabcolsep}@{}}
A & B\\\hline
C & D
\end{tabular}%
     & E \tabularnewline\hline
\hspace{\tabcolsep}F       & G \tabularnewline\hline
\end{longtable}

\end{document}

Answer 2

For the sake of completeness :-)

---

---

\documentclass[final,cmyk,table]{article}
\usepackage%
[%
a0paper,
margin=0cm%
]{geometry}
\usepackage{graphicx}
\usepackage{amsmath}
\usepackage{xcolor}
\usepackage{array}
\usepackage{longtable}
\usepackage{calc}

\makeatletter
\newcommand\ratio[2]{%
  \strip@pt\dimexpr#1pt/#2\relax
}
\makeatother  


\setlength{\arrayrulewidth}{1pt}
\setlength{\tabcolsep}{5pt}
\arrayrulecolor{red}

\newcolumntype{S}[1]%
{%
    >{%
         \begin{minipage}%
         {%
            #1\linewidth-2\tabcolsep-2\arrayrulewidth%
         }%
         \vspace{\tabcolsep}%
    }%
    c%
    <{%
         \vspace{\tabcolsep}%
         \end{minipage}%
    }%
}%

\newcolumntype{O}[1]%
{%
    >{%
        \begin{minipage}%
        {%
             #1\linewidth-2\tabcolsep-1.5\arrayrulewidth%
        }%
        \vspace{\tabcolsep}%
    }%
    c%
    <{%
         \vspace{\tabcolsep}%
         \end{minipage}%
    }%
}%

\newcolumntype{I}[1]%
{%
    >{%
        \begin{minipage}%
        {%
            #1\linewidth-2\tabcolsep-\arrayrulewidth%
        }%
        \vspace{\tabcolsep}%
    }%
    c%
    <{%
        \vspace{\tabcolsep}%
        \end{minipage}%
    }%
}%



\newenvironment{MyCrazyTable}[3]%
{%    
    \begin{tabular}%
    {%
        |>{\centering}O{\ratio{#2}{#1}}%
        |>{\centering}O{\ratio{#3}{#1}}%
        |%
    }%
    \hline\ignorespaces%
}%
{%
    \end{tabular}%
}



\newcommand{\myrow}{%
\includegraphics[width=\linewidth]{newton}%
&%
\includegraphics[width=\linewidth]{newton}%
\tabularnewline\hline%
}




\begin{document}
\noindent%
\begin{longtable}{|S{1}|}
\hline
\begin{MyCrazyTable}{2}{1}{1}%
\begin{MyCrazyTable}{2}{1}{1}%
\begin{MyCrazyTable}{2}{1}{1}%
\begin{MyCrazyTable}{2}{1}{1}%
\begin{MyCrazyTable}{2}{1}{1}%
\begin{MyCrazyTable}{2}{1}{1}%
...                & F\tabularnewline\hline
\myrow
\end{MyCrazyTable} & F\tabularnewline\hline
\myrow
\end{MyCrazyTable} & F\tabularnewline\hline
\myrow
\end{MyCrazyTable} & F\tabularnewline\hline
\myrow
\end{MyCrazyTable} & F\tabularnewline\hline
\myrow
\end{MyCrazyTable} & F\tabularnewline\hline
\myrow
\end{MyCrazyTable}
\tabularnewline\hline
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\begin{MyCrazyTable}{2}{1}{1}%
\begin{MyCrazyTable}{2}{1}{1}%
\begin{MyCrazyTable}{2}{1}{1}%
\begin{MyCrazyTable}{2}{1}{1}%
\begin{MyCrazyTable}{2}{1}{1}%
\begin{MyCrazyTable}{2}{1}{1}%
...                & F\tabularnewline\hline
\myrow
\end{MyCrazyTable} & F\tabularnewline\hline
\myrow
\end{MyCrazyTable} & F\tabularnewline\hline
\myrow
\end{MyCrazyTable} & F\tabularnewline\hline
\myrow
\end{MyCrazyTable} & F\tabularnewline\hline
\myrow
\end{MyCrazyTable} & F\tabularnewline\hline
\myrow
\end{MyCrazyTable}
\tabularnewline\hline
\end{longtable}
\end{document}

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I used this image and renamed it as newton.jpg