Wrap long const assert
diff --git a/src/assert.rs b/src/assert.rs
index cc736dc..738e5bb 100644
--- a/src/assert.rs
+++ b/src/assert.rs
@@ -1,5 +1,5 @@
 macro_rules! const_assert_eq {
-    ($left:expr, $right:expr) => {
+    ($left:expr, $right:expr $(,)?) => {
         const _: [(); $left] = [(); $right];
     };
 }
diff --git a/src/rust_sliceu8.rs b/src/rust_sliceu8.rs
index 6e987a8..f509c7f 100644
--- a/src/rust_sliceu8.rs
+++ b/src/rust_sliceu8.rs
@@ -23,4 +23,7 @@
     }
 }
 
-const_assert_eq!(mem::size_of::<Option<RustSliceU8>>(), mem::size_of::<RustSliceU8>());
+const_assert_eq!(
+    mem::size_of::<Option<RustSliceU8>>(),
+    mem::size_of::<RustSliceU8>(),
+);