grammar 
terminals :: '' ::=
  | <                                   :: :: lt
%    {{ tex \ensuremath{\langle} }}
    {{ tex \ottsym{<} }}
  | >                                   :: :: gt
%    {{ tex \ensuremath{\rangle} }}
    {{ tex \ottsym{>} }}

  | [| :: :: range_start
    {{ tex \mbox{$\ottsym{[\textbar}$} }}       
  | |] :: :: range_end       
    {{ tex \mbox{$\ottsym{\textbar]}$} }}       
  | [|| :: :: list_start
    {{ tex \mbox{$\ottsym{[\textbar\textbar}$} }}       
  | ||] :: :: list_end       
    {{ tex \mbox{$\ottsym{\textbar\textbar]}$} }}       

  | ->                                  :: :: arrow
%    {{ tex \ensuremath{\rightarrow} }}
    {{ tex \ottsym{-\textgreater} }}
    {{ com \texttt{->} }}

  | >=                                  :: :: geq
%    {{ tex \ensuremath{\geq} }}
    {{ tex \ottsym{\textgreater=} }}
    {{ com \texttt{>=} }}
  | '<='                                        :: :: leq
%    {{ tex \ensuremath{\leq} }}
    {{ tex \ottsym{\textless=} }}
    {{ com \texttt{<=} }}