Tests/feaLib/data/spec8a.fea

languagesystem DFLT dflt;
languagesystem latn dflt;
languagesystem latn TRK;
languagesystem cyrl dflt;

feature aalt {
    feature salt;
    feature smcp;
    sub d by d.alt;
} aalt;

feature smcp {
    sub [a - c] by [A.sc - C.sc];
    sub f i by f_i;  # not considered for aalt
} smcp;

feature salt {
    sub a from [a.alt1 a.alt2 a.alt3];
    sub e [c d e]' f by [c.mid d.mid e.mid];
    sub b by b.alt;
} salt;