Struct depends::graphviz::GraphvizVisitor

pub struct GraphvizVisitor { /* private fields */ }

Available on crate feature graphviz only.

A Visitor which builds a Graphviz representation of a given graph.

use depends::graphviz::GraphvizVisitor;

// Compose a graph.
let left = InputNode::new(NumberValue::default());
let left_squared = DerivedNode::new(
    Dependency::new(Rc::clone(&left)),
    Square,
    NumberValue::default(),
);
let right = InputNode::new(NumberValue::default());
let two_numbers = TwoNumbers::init(left_squared, right);
let sum = DerivedNode::new(two_numbers, Add, NumberValue::default());
let sum_squared = DerivedNode::new(Dependency::new(sum), Square, NumberValue::default());

let mut visitor = GraphvizVisitor::new();

// Resolve the graph with this visitor.
// Be sure NOT to use `resolve_root`, as this will clear the visitor's state.
sum_squared.resolve(&mut visitor).unwrap();

println!("{}", visitor.render().unwrap());
// A Graphviz representation is now available on the visitor!
assert_eq!(
    visitor.render().unwrap(),
    r#"
digraph Dag {
  node_0 [label="NumberValue"];
  node_1 [label="NumberValue"];
  node_0 -> node_1 [label="Square"];
  node_2 [label="NumberValue"];
  node_3 [label="NumberValue"];
  node_1 -> node_3 [label="Add", class="TwoNumbersDep"];
  node_2 -> node_3 [label="Add", class="TwoNumbersDep"];
  node_4 [label="NumberValue"];
  node_3 -> node_4 [label="Square"];
}
"#
    .trim()
);

Implementations

impl GraphvizVisitor

pub fn new() -> Self

pub fn render(&self) -> Option<String>

Render the visited graph to Graphviz DOT format. Returns Option::None if no graph has been visited.

Trait Implementations

impl Debug for GraphvizVisitor

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for GraphvizVisitor

fn default() -> GraphvizVisitor

Returns the “default value” for a type.

impl Visitor for GraphvizVisitor

type Hasher = DefaultHasher

fn visit<N>(&mut self, node: &N) -> bool

where N: Identifiable,

Return true iff this node hasn’t been visited yet.

fn clear(&mut self)

Clear the internal collection, prompting this visitor to revisit all nodes on the next traversal.

fn touch<N>(&mut self, node: &N, operation: Option<&'static str>)

where N: Identifiable,

Touch the node. Useful for building graph visualisations.

fn touch_dependency_group(&mut self, dep: &'static str)

Touch a dependency group type. Useful for building graph visualisations.

fn leave<N>(&mut self, node: &N)

where N: Identifiable,

Undo a touch. Useful for building graph visualisations.

fn hasher(&self) -> Self::Hasher

fn notify_recalculated<N>(&mut self, _node: &N)

where N: Identifiable,

For diagnostics, notify that a node has been recalculated.