      \fitem{map}(f:function, t:tab) returns a tab such that element $i$
      is the result of applying \code{f} to element \texttt{t[$i$]}. Note
      that
      \begin{lstlisting}
            @map(f, &$t$&) &$\equiv$& [f($x) | $x in &$t$&]
      \end{lstlisting}


      %%% -------------------------------------------------------

