use references in FixedSizeBytes

Author: antonilol

heed-types/src/bytes.rs

@@ -34,17 +34,17 @@ pub enum FixedSizeBytes<const N: usize> {}
 impl<'a, const N: usize> BytesEncode<'a> for FixedSizeBytes<N> {
     type EItem = [u8; N];
 
-    type ReturnBytes = [u8; N]; // TODO &'a [u8; N] or [u8; N]
+    type ReturnBytes = &'a [u8; N];
 
     type Error = Infallible;
 
     fn bytes_encode(item: &'a Self::EItem) -> Result<Self::ReturnBytes, Self::Error> {
-        Ok(*item)
+        Ok(item)
     }
 }
 
 impl<'a, const N: usize> BytesDecode<'a> for FixedSizeBytes<N> {
-    type DItem = [u8; N]; // TODO &'a [u8; N] or [u8; N]
+    type DItem = &'a [u8; N];
 
     fn bytes_decode(bytes: &'a [u8]) -> Result<Self::DItem, BoxedError> {
         bytes.try_into().map_err(Into::into)