Static library to redefine entrypoint

[Philip K.F. Hölzenspies]

Dear GHCers,

I am trying to write a wrapper library for lab work to give to students.
My problem is, that the libraries I use require initialization that I
really want to hide from our students. The wrapper I'm writing is
compiled to a static library and installed with cabal, so students can
just "ghc --make" or "ghci" their sources. Here comes the problem: I
want to define main and let students just define labMain as an entry
point to their program.

How can I have my library use "labMain" without a definition? Keep in
mind that I want to give them a cabalized library that they can just
link to, so I can't give them a template file that they fill and compile
together with my code. Is it at all possible to have "external"
functions and letting the linker sort stuff out?

Regards,
Philip