Working application

egui_node_graph2/src/index_impls.rs

@@ -0,0 +1,35 @@
+use super::*;
+
+macro_rules! impl_index_traits {
+    ($id_type:ty, $output_type:ty, $arena:ident) => {
+        impl<A, B, C> std::ops::Index<$id_type> for Graph<A, B, C> {
+            type Output = $output_type;
+
+            fn index(&self, index: $id_type) -> &Self::Output {
+                self.$arena.get(index).unwrap_or_else(|| {
+                    panic!(
+                        "{} index error for {:?}. Has the value been deleted?",
+                        stringify!($id_type),
+                        index
+                    )
+                })
+            }
+        }
+
+        impl<A, B, C> std::ops::IndexMut<$id_type> for Graph<A, B, C> {
+            fn index_mut(&mut self, index: $id_type) -> &mut Self::Output {
+                self.$arena.get_mut(index).unwrap_or_else(|| {
+                    panic!(
+                        "{} index error for {:?}. Has the value been deleted?",
+                        stringify!($id_type),
+                        index
+                    )
+                })
+            }
+        }
+    };
+}
+
+impl_index_traits!(NodeId, Node<A>, nodes);
+impl_index_traits!(InputId, InputParam<B, C>, inputs);
+impl_index_traits!(OutputId, OutputParam<B>, outputs);