class special_cleft_extraction_ante 
{
    %% example: le chef c'est lui
    %% example: dormir, c'est mourir un peu                                      
    <: _special_cleft_extraction;
    S >> N2;
    node S2 : [cat: S, id: S];
    S2 >> S;
    S2 >> N1;
    N1 < S;
    node coma : [type : lex, lex : ',', optional: yes];
    S2 >> coma;
    N1 < coma;
    coma < S;
    node(S).bot.extraction = value(cleft);
    %% inspired from _verb_extraction
    node(S2).bot.gender = node(S).bot.gender;
    node(S2).bot.number = node(S).bot.number;
    node(S2).bot.person = node(S).bot.person;
    node(S2).bot.mode = node(S).top.mode;
    node(S2).bot.neg = node(S).top.neg;
    node(S2).bot.sat = node(S).top.sat;
    node(S2).bot.tense = node(S).top.tense;
    node(S2).bot.wh = node(S).top.wh;
    node(S2).bot.inv = node(S).top.inv;
    node(S2).top.extraction = value(-);
    node(NS1).top.mode = value(infinitive);
    node(NS1).top.extraction= value(-);
}