Question: Removing unused lookup entries during compilation

[mainrs]

Is it possible to remove unused lookup tables if the lookups are known at compile time? For example, if I have a map full of values but a user of a library only needs one or two values out of it.

I am not sure if Rust is capable of doing this. I think storing the return type inside a const variable would do the trick, as it would move the data into the user's application, but that would mean that get had to be const as well.

[abonander]

While this is certainly conceivable within the context of const fn, it would require impl const Trait: rust-lang/rfcs#2632