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/* [estyx.abs]                 Abstract Grammar                             */
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LANGUAGE estyx

TOKENS

  Ide, Set, Seq

TYPES

  estyx       = Start_Source(Source)

  Source      = root(Ide, QlxDfn*, Dfn*)

  QlxDfn      = defn(QlxCat, QlxOpt, Ide, Exp)

  QlxCat      = letC;
                comC;
                ignC;
                tokC

  QlxOpt      = non;
                ignca

  Exp         = range(Exp, Exp);
                opt(Exp);
                union(Exp, Exp);
                conc(Exp, Exp);
                plus(Exp);
                ident(Ide);
                diff(Exp, Exp);
                sequ(Seq);
                set(Set);
                star(Exp)

  Dfn         = defn(Cat, Ide, Prd*)

  Cat         = letC;
                bgnC

  Prd         = prod(Ide, Mbr*)

  Mbr         = tkm(Seq);
                ntm(Form)

  Form        = one(Form, Seq*);
                ide(Ide);
                nul(Seq*, Form, Seq*, Seq*)