[Haskell-beginners] Export of names only for testing

[Baa]

> It is common to export an Foo.Internal module that has the internals
> of your library in it, with a doc at the top that this is meant for
> internal use.  It can be used both for testing and sometimes the user
> of your library can do something with it you didn't think of if he
> has access to the internals.

Hm, but if I have 10 modules in src/ (m1.hs, ..., m10.hs) I must create,
for example 10 folders like src/m1/, ..., src/m10/ and their individual
M*.Internal module, right? So, `m1`, for example, becomes:

  src/
    m1/
      Internal.hs
      All.hs
?

And `All.hs` imports and re-exports module (or its part only)
`Internal.hs`? Something like this?


===
Best regards, Paul