how to checkout proper submodules

[Daniel Trstenjak]

Hi Geoffrey,

> I don't know much about subtrees, but that might be another possibility?

the main point about subtrees is, that you've just one repository and
you're merging a directory of this repository with 'git subtree' with
some other git repository.

subtrees and submodules both try to handle the use case if you want to
incorporate a third party repository into your own repository and would
like to merge the changes in both directions.

I think that subtrees are easier for the developer working on the
repository, because there's only one repository, but it's a bit more
hassle merging the third party repository.

submodules are harder for the developer, because there're multiple
repositories, but merging the third party repository might be a bit
easier.

GHC devs might have other reasons for using submodules, because they want
to separate things or they're afraid that the resulting one repository
might get too big, but I think that there should be good reasons for
using submodules, because a lot of workflows (like branching) are such
a hassle with submodules.


Greetings,
Daniel