Working example

src/foreign_macros/atomic_defaults.rs

@@ -0,0 +1,19 @@
+#[allow(unused)] // for the doc comments
+use crate::foreign::Atomic;
+
+/// A macro that generates the straightforward, syntactically invariant part of implementing
+/// [Atomic]. Implemented fns are [Atomic::as_any], [Atomic::definitely_eq] and [Atomic::hash].
+/// 
+/// It depends on [Eq] and [Hash]
+#[macro_export]
+macro_rules! atomic_defaults {
+  () => {
+    fn as_any(&self) -> &dyn std::any::Any { self }
+    fn definitely_eq(&self, _other: &dyn std::any::Any) -> bool {
+      _other.downcast_ref().map(|o| self == o).unwrap_or(false)
+    }
+    fn hash(&self, mut hasher: &mut dyn std::hash::Hasher) {
+      <Self as std::hash::Hash>::hash(self, &mut hasher)
+    }
+  };
+}