digraph block {
    N0[label="entry"];
    N1[label="exit"];
    N2[label="expr 7i"];
    N3[label="expr 77i"];
    N4[label="expr 777i"];
    N5[label="expr 7777i"];
    N6[label="expr [7i, 77i, 777i, 7777i]"];
    N7[label="expr match [7i, 77i, 777i, 7777i] { [x, y, ..] => x + y }"];
    N8[label="local x"];
    N9[label="local y"];
    N10[label="pat .."];
    N11[label="pat [x, y, ..]"];
    N12[label="expr x"];
    N13[label="expr y"];
    N14[label="expr x + y"];
    N15[label="block { match [7i, 77i, 777i, 7777i] { [x, y, ..] => x + y }; }"];
    N0 -> N2;
    N2 -> N3;
    N3 -> N4;
    N4 -> N5;
    N5 -> N6;
    N6 -> N8;
    N8 -> N9;
    N9 -> N10;
    N10 -> N11;
    N11 -> N12;
    N12 -> N13;
    N13 -> N14;
    N14 -> N7;
    N7 -> N15;
    N15 -> N1;
}