digraph block {
    N0[label="entry"];
    N1[label="exit"];
    N2[label="expr 5"];
    N3[label="expr 55"];
    N4[label="expr (5, 55)"];
    N5[label="local _x"];
    N6[label="local _y"];
    N7[label="pat (_x, _y)"];
    N8[label="stmt let (_x, _y) = (5, 55);"];
    N9[label="block { let (_x, _y) = (5, 55); }"];
    N0 -> N2;
    N2 -> N3;
    N3 -> N4;
    N4 -> N5;
    N5 -> N6;
    N6 -> N7;
    N7 -> N8;
    N8 -> N9;
    N9 -> N1;
}