% grammar.hva
%
% COPYRIGHT (c) 1999 Bell Labs, Lucent Technologies.
%
% HeVeA macro definitions to simulate the grammar.sty commands.
%

\newboolean{GGanchors}		% true means lhs nonterm is anchor
\newboolean{GGfirstrule}
\newboolean{GGfirstrhs}
\newcommand{\GGfirstcell}{
  \@open{TD}{WIDTH="20"}
  \@close{TD}
}
\newcommand{\GGsepsymb}{
  \GGfirstcell{}
  \ifthenelse{\boolean{GGfirstrhs}}{
    \@open{TD}{ALIGN=CENTER VALIGN=BOTTOM}
    ::=
    \@close{TD}
    \setboolean{GGfirstrhs}{false}
  }{
    \@open{TD}{ALIGN=CENTER VALIGN=BOTTOM}
    |
    \@close{TD}
  }
}

\newcommand{\GGRHS}[2][]{
  \@open{TR}{}
  \GGsepsymb{}
  \@open{TD}{NOWRAP VALIGN=BOTTOM}
  #2
  \@close{TD}
  \@open{TD}{ALIGN=RIGHT VALIGN=TOP}
  #1
  \@close{TD}
  \@close{TR}
}
\newcommand{\GGCONT}[1]{
  \@open{TR}{}
  \@open{TD}{COLSPAN="2"}
  \@close{TD}
  \@open{TD}{NOWRAP VALIGN=BOTTOM}
  \@print{  }
  #1
  \@close{TD}
  \@close{TR}
}
\newcommand{\GGITEM}[1]{%
  \ifthenelse{\boolean{GGfirstrhs}}{\setboolean{GGfirstrhs}{false}}{
    \@print{  |  }
  }%
  #1
}

%
% font commands
\newcommand{\kw}[1]{{\@style{B}{\@style{TT}#1}}}
\newcommand{\GGnt}[1]{{\@style{I}#1}}
\newcommand{\nt}[1]{\GGnt{\url{\#nt:#1}{#1}}}
\newcommand{\term}[1]{{\@style{I}#1}}
\newcommand{\sym}[1]{\kw{#1}}

\newenvironment{Grammar}[1][]{%
  \setboolean{GGanchors}{\equal{#1}{anchors}}%
  \setboolean{GGfirstrule}{true}%
  \newcommand{\GRP}[1]{$(\text{##1})$}%
  \newcommand{\OPT}[1]{$\text{\protect{##1}}^{\textit{opt}}$}%
  \newcommand{\OPTGRP}[1]{$(\text{##1})^{\textit{opt}}$}%
  \newcommand{\LIST}[1]{$\text{\protect{##1}}^{*}$}%
  \newcommand{\LISTGRP}[1]{$(\text{##1})^{*}$}%
  \newcommand{\LISTONE}[1]{$\text{\protect{##1}}^{+}$}%
  \newcommand{\LISTONEGRP}[1]{$(\text{##1})^{+}$}%
  \newenvironment{Rules}[1]{%
    \setboolean{GGfirstrhs}{true}%
    \newcommand{\RHS}{\GGRHS}%
    \newcommand{\CONT}{\GGCONT}%
    \ifthenelse{\boolean{GGfirstrule}}{
      \setboolean{GGfirstrule}{false}%
    }{
      \@open{TR}{}
        \@open{TD}{}\@print{ }\@close{TD}
      \@close{TR}
    }
    \@open{TR}{}
    \@open{TD}{ALIGN=LEFT COLSPAN="3"}
      \ifthenelse{\boolean{GGanchors}}{\anchor{nt:##1}}{}
      \GGnt{##1}
    \@close{TD}
    \@close{TR}
  }{%
  }
  \newenvironment{OneOfRule}[1]{%
    \setboolean{GGfirstrhs}{true}%
    \newcommand{\ITEM}{\GGITEM}%
    \ifthenelse{\boolean{GGfirstrule}}{}{
      \@open{TR}{}
        \@open{TD}{}\@print{ }\@close{TD}
      \@close{TR}
    }
    \@open{TR}{}
      \@open{TD}{ALIGN=LEFT COLSPAN="3"}
      \ifthenelse{\boolean{GGanchors}}{\anchor{nt:##1}}{}
      \GGnt{##1}
      \@close{TD}
    \@close{TR}
    \@open{TR}{}
    \GGfirstcell{}
    \@open{TD}{ALIGN=CENTER VALIGN=BOTTOM}
    ::=
    \@close{TD}
    \@open{TD}{}
  }{%
    \@close{TD}
    \@close{TR}
  }
  \@open{TABLE}{}
}{%
  \@close{TABLE}
}