[dschwoerer]

The BOUT++ provided slope limiters are all instantiated, using the previous header file.

If a user wants to use a different slope limiter, they can #include the implementation header (or just upstream, as one should).

[github-actions]

clang-tidy made some suggestions

[ZedThree]

Nice! Very clever implementation of this.

There's just a few bits of commented out code to clean up, and as we're touching this, may as well fix the clang-tidy warnings. Then we're ratcheting our way to being totally warning clean!

It would also be good to just add something to the docstrings of these functions about how to add a new limiter without upstreaming it.

[ZedThree]

Please could you just add something about needing to include fv_ops_impl and/or adding an explicit instantiation in order to add a new flux limiter? Then I think this is good to go

[dschwoerer]

Sorry, forgot about them. Should be good now.

[dschwoerer]

Now we could also make this a configurable runtime choice.
But I do not feel strongly enough about it to implement it.

[ZedThree]

Making it a runtime choice would be neat, but can be done later