Due to the large amount of variants, and the different kind of values
connected to each variant (hash, extension name) being scattered
across the various `impl` blocks, the file became rather convoluted.
While I don't generally like the indirection of macros or meta
programming, it's not that bad with Rust, thanks to Rust Analyzer being
able to attach diagnostics to the source inside the macro definition,
and the ability to generate the macro's output for validation.
Therefore, the new macro allows putting all data used for this enum
definition into a single block.
Lucas Schwiderski
5f8016c655
