primitive: Move `.weight()` method to a new `GetWeight` trait

src/draw.rs

@@ -7,6 +7,7 @@ use crate::{
     guide::Guide,
     layout::Layout,
     math::Circle,
+    primitive::GetWeight,
     rules::{Conditions, Rules},
     segbend::Segbend,
 };

src/guide.rs

@@ -5,7 +5,7 @@ use crate::{
     graph::{BendIndex, DotIndex},
     layout::Layout,
     math::{self, Circle},
-    primitive::MakeShape,
+    primitive::{GetWeight, MakeShape},
     rules::{Conditions, Rules},
 };
 

src/layout.rs

@@ -12,7 +12,7 @@ use crate::graph::{
     BendIndex, BendWeight, DotIndex, DotWeight, GenericIndex, GetNodeIndex, Index, Interior, Label,
     Retag, SegIndex, SegWeight, Weight,
 };
-use crate::primitive::{GenericPrimitive, MakeShape};
+use crate::primitive::{GenericPrimitive, GetWeight, MakeShape};
 use crate::segbend::Segbend;
 use crate::shape::{Shape, ShapeTrait};
 

src/primitive.rs

@@ -11,6 +11,11 @@ use crate::graph::{
 use crate::math::{self, Circle};
 use crate::shape::{BendShape, DotShape, SegShape, Shape, ShapeTrait};
 
+#[enum_dispatch]
+pub trait GetWeight<W> {
+    fn weight(&self) -> W;
+}
+
 #[enum_dispatch]
 pub trait MakeShape {
     fn shape(&self) -> Shape;
@@ -248,8 +253,10 @@ impl<'a> Dot<'a> {
             .filter(|bend| self.primitive(*bend).inner().is_none())
             .next()
     }
+}
 
-    pub fn weight(&self) -> DotWeight {
+impl<'a> GetWeight<DotWeight> for Dot<'a> {
+    fn weight(&self) -> DotWeight {
         self.tagged_weight().into_dot().unwrap()
     }
 }
@@ -272,8 +279,10 @@ impl<'a> Seg<'a> {
     pub fn prev(&self) -> Option<DotIndex> {
         self.prev_node().map(|ni| DotIndex::new(ni))
     }
+}
 
-    pub fn weight(&self) -> SegWeight {
+impl<'a> GetWeight<SegWeight> for Seg<'a> {
+    fn weight(&self) -> SegWeight {
         self.tagged_weight().into_seg().unwrap()
     }
 }
@@ -334,10 +343,6 @@ impl<'a> Bend<'a> {
         self.prev_node().map(|ni| DotIndex::new(ni))
     }
 
-    pub fn weight(&self) -> BendWeight {
-        self.tagged_weight().into_bend().unwrap()
-    }
-
     fn inner_radius(&self) -> f64 {
         let mut r = 0.0;
         let mut layer = BendIndex::new(self.index.node_index());
@@ -368,6 +373,12 @@ impl<'a> Bend<'a> {
     }
 }
 
+impl<'a> GetWeight<BendWeight> for Bend<'a> {
+    fn weight(&self) -> BendWeight {
+        self.tagged_weight().into_bend().unwrap()
+    }
+}
+
 impl<'a> MakeShape for Bend<'a> {
     fn shape(&self) -> Shape {
         let ends = self.ends();

src/router.rs

@@ -8,6 +8,7 @@ use crate::layout::Layout;
 
 use crate::math::Circle;
 use crate::mesh::{Mesh, MeshEdgeReference, VertexIndex};
+use crate::primitive::GetWeight;
 use crate::rules::Rules;
 use crate::tracer::{Trace, Tracer};
 

src/tracer.rs

@@ -6,7 +6,7 @@ use crate::{
     graph::{BendIndex, DotIndex, Ends},
     layout::Layout,
     mesh::{Mesh, VertexIndex},
-    primitive::MakeShape,
+    primitive::{GetWeight, MakeShape},
     rules::Rules,
 };