Notably these diverge from rust, by requiring argument names. This is a
deliberate design decision, as it help users to guess what's going to be
passed into their callback.
This changes two important things:
- Firstly it renames the `nasp` keyword to `mod`:
This change removes the not required deviation from rust.
- Secondly it removes the semicolon after an enumeration or structure
declaration, which is pointless in these positions.