class S_enum 
{
    <: simple_enum;
    node(Root).cat = value(S);
    $type = value(subst);
    block1::Coord : [top: [sat: -, mode: $mode ^ ~ imperative, extraction: $extraction, wh: $wh, xarg: $xarg, control: $control ]];
    block3::Coord : [top: [sat: -, mode: $mode, extraction: $extraction, wh: $wh, xarg: $xarg, control: $control ]];
    node(block1::Coord).bot.mode = node(Foot).bot.mode;
    node(Root).bot.mode = node(Foot).bot.mode;
%    node(Root).bot.extraction = $extraction;
    node(Root).bot.sat = value(-);
     node(Root).top.sat = value(-);
     node(Foot).bot.sat = value(-);
    node(Root).bot.extraction =  node(Foot).bot.extraction;
    node(Root).bot.xarg=node(Foot).bot.xarg;
    node(Foot).bot.sat = value(-);
    node(Root).bot.control = node(Foot).bot.control;
    node(Foot).bot.xarg.trace = value(-);
    %% coord do not change many S features
    %% should have a way to express that in a easier way
    node(Root).bot.inv = node(Foot).bot.inv;
    node(Root).bot.cat = node(Foot).bot.cat;
    node(Root).bot.tense = node(Foot).bot.tense;
    node(Root).bot.neg = node(Foot).bot.neg;
    node(Root).bot.person = node(Foot).bot.person;
    node(Root).bot.gender = node(Foot).bot.gender;
    node(Root).bot.wh = node(Foot).bot.wh;
    node(Root).bot.number = node(Foot).bot.number;
    %% sometime we coordinate sentences build with a mod_extraction
    %% we have a pb because verb_*_extraction_* require its foot to be
    %% extraction in estcaue|adjx
    %% example: où habites-tu et que fais-tu ?
    %% example: j'aime cette maison où tu habites et que tu veux quitter
    %% however, the following constraint doesn't rule out the coord of a
    %% wh-sentence with a relative sentence !
    %% maybe we should use the wh-feature to indicate that we are inside a
    %% relative  sentence
    block1::Coord +
        node(Root).bot.extraction = $extraction
        |
        node(Foot).top.extraction = value(estceaux|adjx),
    node(Foot).top.wh = node(block1::Coord).bot.wh
        ;
    node(Foot).top.control = node(block1::Coord).bot.control
        ;
}