xdot/layout/
graph_ext.rs

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1use std::iter::{empty, once};
2
3use graphviz_rust::dot_structures::{Edge, Graph, Node, Stmt, Subgraph};
4
5pub(super) enum Elem<'a> {
6    Node(&'a Node),
7    Edge(&'a Edge),
8}
9
10pub(super) trait GraphExt {
11    fn iter_elems<'a>(&'a self) -> Box<dyn Iterator<Item = Elem<'a>> + 'a>;
12}
13
14impl GraphExt for Stmt {
15    fn iter_elems<'a>(&'a self) -> Box<dyn Iterator<Item = Elem<'a>> + 'a> {
16        match self {
17            Stmt::Edge(edge) => Box::new(once(Elem::Edge(edge))),
18            Stmt::Node(node) => Box::new(once(Elem::Node(node))),
19            Stmt::Subgraph(sg) => sg.iter_elems(),
20            _ => Box::new(empty()),
21        }
22    }
23}
24
25impl GraphExt for Subgraph {
26    fn iter_elems<'a>(&'a self) -> Box<dyn Iterator<Item = Elem<'a>> + 'a> {
27        Box::new(self.stmts.iter().flat_map(Stmt::iter_elems))
28    }
29}
30
31impl GraphExt for Graph {
32    fn iter_elems<'a>(&'a self) -> Box<dyn Iterator<Item = Elem<'a>> + 'a> {
33        let stmts = match self {
34            Graph::Graph { stmts, .. } => stmts,
35            Graph::DiGraph { stmts, .. } => stmts,
36        };
37        Box::new(stmts.iter().flat_map(Stmt::iter_elems))
38    }
39}
xdot/layout/graph_ext.rs

xdot/layout/
graph_ext.rs
