error: generic `Self` types are currently not permitted in anonymous constants --> $DIR/issue-47814.rs:8:32 | LL | pub fn to_buffer() -> [u8; Self::LENGTH] { | ^^^^ | note: not a concrete type --> $DIR/issue-47814.rs:5:10 | LL | impl<'a> ArpIPv4<'a> { | ^^^^^^^^^^^ error: aborting due to 1 previous error