Restrict static params of our types, so e.g. PolyRing{T} now always must satisfy T<:RingElement

[fingolfin]

This gives a lot of extra hints to JET and also Julia itself.

It should also help to catch certain human errors. And it also gives developers a hint what those type params are (I certainly struggled with that when I started out).

But I am sure this also will break some code (and perhaps even uncover a bug here or there), or it might even turn out to be infeasible after all.

The idea came to me during some debugging last night and I thought I'd give it a quick try...

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 88.15%. Comparing base (e271241) to head (7c6ee86).

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #2286      +/-   ##
==========================================
+ Coverage   88.12%   88.15%   +0.03%     
==========================================
  Files         126      126              
  Lines       32108    32108              
==========================================
+ Hits        28294    28305      +11     
+ Misses       3814     3803      -11     

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[lgoettgens]

Is this "breaking" as in it actually breaks some of our code, or is it just "theoretically breaking"? Or do we need to wait for working downstream tests to see that?

[fingolfin]

It should not be breaking in practice. But we know how it is ... I'd not be surprised if some code out there is broken. So I really would like to wait till the upstream tests are restored.

[lgoettgens]

Downstream tests seem unhappy, but it is not immediately clear to me why

[lgoettgens]

Downstream tests seem unhappy, but it is not immediately clear to me why

The current error seems to be due to a typo in a signature in Oscar, which will be fixed by oscar-system/Oscar.jl#5724. Let's re-run CI again once that is in to see if it breaks anything more.

But nonetheless, the "breaking" label should now stay, even if with future patches to Oscar the CI becomes green.

[lgoettgens]

good to go in the next breaking release