Method add_edge

datafusion/common/src/display/graphviz.rs:94–104

(
        &self,
        f: &mut fmt::Formatter,
        from_id: usize,
        to_id: usize,
    )

    }

    pub fn add_edge(
        &self,
        f: &mut fmt::Formatter,
        from_id: usize,
        to_id: usize,
    ) -> fmt::Result {
        writeln!(
            f,
            "    {from_id} -> {to_id} [arrowhead=none, arrowtail=normal, dir=back]"
        )
    }
}