Optional render config

src/hugr/views.rs

@@ -2,7 +2,7 @@
 
 pub mod descendants;
 pub mod petgraph;
-mod render;
+pub mod render;
 mod root_checked;
 pub mod sibling;
 pub mod sibling_subgraph;
@@ -13,6 +13,7 @@ mod tests;
 use std::iter::Map;
 
 pub use self::petgraph::PetgraphWrapper;
+use self::render::RenderConfig;
 pub use descendants::DescendantsGraph;
 pub use root_checked::RootChecked;
 pub use sibling::SiblingGraph;
@@ -356,6 +357,23 @@ pub trait HugrView: sealed::HugrInternals {
     /// For a more detailed representation, use the [`HugrView::dot_string`]
     /// format instead.
     fn mermaid_string(&self) -> String
+    where
+        Self: Sized,
+    {
+        self.mermaid_string_with_config(RenderConfig {
+            port_offsets_in_edges: true,
+            type_labels_in_edges: true,
+        })
+    }
+
+    /// Return the mermaid representation of the underlying hierarchical graph.
+    ///
+    /// The hierarchy is represented using subgraphs. Edges are labelled with
+    /// their source and target ports.
+    ///
+    /// For a more detailed representation, use the [`HugrView::dot_string`]
+    /// format instead.
+    fn mermaid_string_with_config(&self, config: RenderConfig) -> String
     where
         Self: Sized,
     {
@@ -365,7 +383,7 @@ pub trait HugrView: sealed::HugrInternals {
             .mermaid_format()
             .with_hierarchy(&hugr.hierarchy)
             .with_node_style(render::node_style(self))
-            .with_edge_style(render::edge_style(self, true, true))
+            .with_edge_style(render::edge_style(self, config))
             .finish()
     }
 
@@ -378,12 +396,13 @@ pub trait HugrView: sealed::HugrInternals {
     {
         let hugr = self.base_hugr();
         let graph = self.portgraph();
+        let config = RenderConfig::default();
         graph
             .dot_format()
             .with_hierarchy(&hugr.hierarchy)
             .with_node_style(render::node_style(self))
             .with_port_style(render::port_style(self))
-            .with_edge_style(render::edge_style(self, false, false))
+            .with_edge_style(render::edge_style(self, config))
             .finish()
     }
 

src/hugr/views/render.rs

@@ -8,6 +8,16 @@ use crate::ops::OpName;
 use crate::types::EdgeKind;
 use crate::HugrView;
 
+/// Configuration for rendering a HUGR graph.
+#[derive(Copy, Clone, Debug, Default, PartialEq, Eq, Hash)]
+#[non_exhaustive]
+pub struct RenderConfig {
+    /// Show port offsets in the graph edges.
+    pub port_offsets_in_edges: bool,
+    /// Show type labels on edges.
+    pub type_labels_in_edges: bool,
+}
+
 /// Formatter method to compute a node style.
 pub(super) fn node_style<H: HugrView>(h: &H) -> Box<dyn FnMut(NodeIndex) -> NodeStyle + '_> {
     Box::new(move |n| {
@@ -42,8 +52,7 @@ pub(super) fn port_style<H: HugrView>(h: &H) -> Box<dyn FnMut(PortIndex) -> Port
 #[allow(clippy::type_complexity)]
 pub(super) fn edge_style<H: HugrView>(
     h: &H,
-    port_offsets_in_edges: bool,
-    type_labels_in_edges: bool,
+    config: RenderConfig,
 ) -> Box<
     dyn FnMut(
             <H::Portgraph<'_> as LinkView>::LinkEndpoint,
@@ -72,7 +81,11 @@ pub(super) fn edge_style<H: HugrView>(
         // Compute the label for the edge, given the setting flags.
         //
         // Only static and value edges have types to display.
-        let label = match (port_offsets_in_edges, type_labels_in_edges, port_kind) {
+        let label = match (
+            config.port_offsets_in_edges,
+            config.type_labels_in_edges,
+            port_kind,
+        ) {
             (true, true, EdgeKind::Static(ty) | EdgeKind::Value(ty)) => {
                 format!("{}:{}\n{ty}", src_offset.index(), tgt_offset.index())
             }