hana::Foldableis known at compile-time. You shouldn't need to put it in a run-time list.
enums? (I might just ask myself to reevaluate what I'm using an
enumfor and see if I can't create a class that does it at least as well and interoperates with Hana directly, but I figured I'd ask before reinventing the wheel.)
hana::type_tagis not a higher order data-type.
metafunction& al helpers.