Specify _ name for function arguments
diff --git a/src/isomorphism.rs b/src/isomorphism.rs
index 8632dde..1554b37 100644
--- a/src/isomorphism.rs
+++ b/src/isomorphism.rs
@@ -201,7 +201,7 @@
 
 trait SemanticMatcher<T> {
     fn enabled() -> bool;
-    fn eq(&mut self, &T, &T) -> bool;
+    fn eq(&mut self, _: &T, _: &T) -> bool;
 }
 
 struct NoSemanticMatch;