[CMake] External Projects: just what are they?

[Michael Powell]

On Wed, Sep 27, 2017 at 11:17 PM, Michael Powell <mwpowellhtx at gmail.com> wrote:
> Hello,
>
> I am trying to understand external projects. What are they? What kind
> of support is there for them?

Based on a couple of the blogs I read about it, I'm not sure this is
trying to do too much, but I could be wrong.

In my scenario, I simply have a Git Submodule committed to my
repository that I want to update, then include/invoke/etc its
CMakeLists as an "external project".

So at best, maybe I could invoke ExternalProject_Add with
GIT_SUBMODULES "${MYPROJ_SOURCE_DIR}/repos/mysubmod".

Or am I missing something?

Thoughts? Suggestions?

> I found: https://cmake.org/cmake/help/v3.9/module/ExternalProject.html#command:externalproject_add
>
> For instance.
>
> I have a Git Submodule which I want to support. It represents a core
> library that is essential for a wrapper piece. If I understand
> correctly, technically it is an "external" project, but is there
> support for Git Submodules? And how does that work exactly?
>
> Ideally, I'd like to include the Submodule CMakeLists.txt from the
> context of my wrapper piece, but is this even possible?
>
> Thanks!
>
> Cheers,
>
> Michael Powell