Can containers depend on Template Haskell?

[Henning Thielemann]

Milan Straka schrieb:

> I was considering doing this in some containers-exposed-by-th package, but
> if the containers could do it by themselves, that would be awesome.
> Of course the package could be still compiled by other compilers, it
> would just not export the implementations.

That's not possible - a package at a specific version must export the
same API independent of the compiler, operating system and so on.