proc main()
{
    var a;

    // Simple case
    a = #{#{1,2},#{3,4}};
    "", a.parent, '\n';
    "", a[0,0].parent, '\n';
    "", a, '\n', '\n';

    a = #{#{[1,2],[3,4]},#{[5,6],[7,8]}};
    "", a.parent, '\n';
    "", a[0,0].parent, '\n';
    "", a, '\n', '\n';

    a = #{#{{1,2},{3,4}},#{{5,6},{7,8}}};
    "", a.parent, '\n';
    "", a[0,0].parent, '\n';
    "", a, '\n', '\n';

    a = #{#{"1","2"},#{"3","4"}};
    "", a.parent, '\n';
    "", a[0,0].parent, '\n';
    "", a, '\n', '\n';
}