languagesystem DFLT dflt;

@base_glyphs = [a b c];

@above_base = [caron caron.alt];
@below_base = [commabelowcmb brevebelowcmb];

feature test {

    lookup one {
        lookupflag UseMarkFilteringSet @above_base;

        sub a' @base_glyphs b by c;
    } one;

    lookup two {
        lookupflag UseMarkFilteringSet @below_base;

        sub b' @base_glyphs c by b;
    } two;
    
    lookup three {
        lookupflag UseMarkFilteringSet @below_base;

        sub a @base_glyphs c' by a;
    } three;

} test;
