David M. Lary

> Looks to be well thought out. Love the unit tests. I'd like to see some tests with multiple copies of the same system in a schedule, and some with...

> Does this support time travel? Or I should say, going back into the past? No, for that you either need to implement the command pattern (for undo), or use...

Looking at the changes I made to both single-thread and multi-thread executors, I think the stepping state (which is the same between the two) should be moved into the `SystemSchedule`....

TL;DR: To implement stepping, there must be some complexity added. For the broadest benefit to users, that complexity should be on the system-implementers for render, input, and windowing, otherwise stepping...

> After implementing pause functionality in my game, it's struck me that, by and large, I want to group this stepping (and pause) behavior based on the data that the...

> > BUT! Oh, does this mean there's a way to tell from the System object that a system reads some events? If so, we could automatically handle the ignore_stepping()...

> > I've set up the following test to print the Access values for an event-based system, and both Access methods contain nothing: > > > let system = IntoSystem::into_system(event_system);...

Followup on the detecting event reader systems; I got it working, but it requires `World`. Dropping the code here so I don't lose it: ```rust /// helper function to determine...

Note, this is only the unix implementation. I do not have access to a windows development environment to add the implementation for that side. It's not a complicated change, but...

TL;DR: Pushing a change to reduce processing when prompt changes. Linenoise approach is out-of-scope for this PR, but I am looking at how to do something similar. ### Reduce computation...