start with pointer

src/strategies.rs

@@ -0,0 +1,47 @@
+use crate::StuffingStrategy;
+
+unsafe impl StuffingStrategy for () {
+    type Extra = ();
+
+    fn is_extra(_data: usize) -> bool {
+        false
+    }
+
+    fn stuff_extra(_inner: Self::Extra) -> usize {
+        0
+    }
+
+    fn extract_extra(_data: usize) -> Self::Extra {
+        ()
+    }
+}
+
+#[cfg(test)]
+pub mod test_strategies {
+    use crate::StuffingStrategy;
+    use std::fmt::{Debug, Formatter};
+
+    pub struct HasDebug;
+
+    impl Debug for HasDebug {
+        fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
+            f.write_str("hello!")
+        }
+    }
+
+    unsafe impl StuffingStrategy for HasDebug {
+        type Extra = Self;
+
+        fn is_extra(data: usize) -> bool {
+            data == usize::MAX
+        }
+
+        fn stuff_extra(_inner: Self::Extra) -> usize {
+            usize::MAX
+        }
+
+        fn extract_extra(_data: usize) -> Self::Extra {
+            Self
+        }
+    }
+}