digraph {
    node [shape="point"]
    Inst [shape="oval",label="While"]
    Const [shape="oval",label="Const"]
    True [shape="oval",label="True"]
    Break [shape="oval",label="Break"]
    Others [shape="oval",label="..."]

    Root -> UserA [label="user A"]
    UserA -> Frame [label="'frame'"]
    Frame -> Symbols [label="'symbols'"]
    Frame -> Inst [label="'IP'",constraint="false"]
    Frame -> EvalStack [label="'evalstack'"]
    Frame -> Phase [label="'phase'"]
    Frame -> ReturnValue [label="'returnvalue'"]

    Inst -> Const [label="'cond'"]
    Const -> True [label="'value'"]
    Inst -> Break [label="'body'"]
    Break -> Inst [label="'while'"]
    Inst -> Others [label="'next'"]
}