Chris Russell

Whoops, these types got changed by #7905 after my last fetch. Let me rebase and try again.

Would it make sense to have a function that creates a `SystemState` from a `SystemBuilder`? I think you have all the necessary values available. That would make dynamic system params...

This has an unfortunate interaction with `impl Clone for FunctionSystem`, which will reset the `param_state` of a cloned system and lose the data passed in by the builder. (I don't...

I think you need `fn foo() -> impl Fn() + Sync + Send + 'static {`. `System` requires those trait bounds, and for `ConcreteFoo` the compiler can see the actual...

> In general, not a fan of how we are going back-and-forth on the failure behavior of `Single`. Yeah, I agree that the constant breaking changes are bad! I'm optimistic...

I see two basic ways to fix this: either prevent dense to sparse transmutes, or make `Option` and `Has` always work on dense queries. Preventing dense to sparse transmutes could...

Looking at this again, I have no idea why I thought #14628 had the same root cause! That one doesn't involve sparse set components at all. I'll remove that from...

The changes look reasonable, but it seems like a rebase would change enough that I should wait before clicking Approve. I don't quite follow the motivation. It seems like the...

> The core issue is that we cannot validate params anywhere, but directly before running a system. In case of `a.pipe(b)` system `a` can invalidate `b`s params. With this restraint,...

Ooh, this would be really cool! This might enable us to define pipe systems using ordinary function systems: ```rust fn pipe(input: S1::Input, runners: ParamSet) -> S2::Out { let value =...