It seems like the main difference with a reducer is that the reducer just returns `state`, not `(state, action)`. I'm reading this for the first time but that's how I'm reading it.
But y'all must be storing this `(point-in-time-state, action-that-produced-state)` somewhere, because the Redux Chrome plugin displays this data. Was I wrong in thinking the Chrome plugin was just visualizing data already stored by Redux?
No, the core Redux store does _not_ store any action history by itself. It's simply:
function createStore(reducer) {
var state
var listeners = []
function getState() { return state }
function dispatch(action) {
state = reducer(state, action)
listeners.forEach(listener => listener())
}
}
It's the Redux DevTools that do the real work of actually saving an action log, like what was described above. In fact, canceling actions does actually work by re-running the actions in the same sequence, minus the ones that are being skipped, to generate the new state.
Very vaguely related side note: earlier this year, I spent a couple days to add an "action stack trace" tab to the Redux DevTools Extension. When you click on an action, in addition to seeing the action contents, state tree, and diff, you can now also see an actual formatted stack trace that shows you exactly where the action was dispatched from (including the actual code if you've got sourcemaps enabled). Sadly, the extension maintainer has been MIA recently, so we're considering forking it into the Redux org. Until then, you can download my custom build of the extension here: https://github.com/zalmoxisus/redux-devtools-extension/issue...
That's really interesting. I honestly haven't given Redux DevTools much thought despite the fact I use it daily as a core part of my workflow. I thought, like I said before, it was mostly just visualizing artifacts produced normally by Redux. Makes the browser extension much more interesting!
But y'all must be storing this `(point-in-time-state, action-that-produced-state)` somewhere, because the Redux Chrome plugin displays this data. Was I wrong in thinking the Chrome plugin was just visualizing data already stored by Redux?