Alright, let me walk you through this thing I tinkered with recently, setting up some watches to fire one after another. It wasn’t anything groundbreaking, just a little exercise I wanted to get hands-on with.
Getting Started
So, the basic idea was simple: make something happen, have a watcher catch it, which then makes another thing happen, caught by a second watcher, and so on. Like a little Rube Goldberg machine in code.
First up, I needed a place to run this. Just spun up a simple environment, nothing fancy. Grabbed a basic setup I use for these kinds of tests. The goal wasn’t complexity, just seeing the sequence work.
I started by defining the first thing to watch. Let’s say it was a simple variable, `status_A`. I wrote a small piece of code that would change this `status_A` from ‘idle’ to ‘triggered’. Then, I attached the first watcher to it. The watcher’s job was just to log a message like “Watcher A fired!” and then immediately change another variable, `status_B`.
Building the Chain
Okay, step one done. `status_A` changes, Watcher A notices and logs, then flips `status_B`. Now for the “in succession” part. I basically repeated the process.
I set up Watcher B. This one’s target was `status_B`. Its instructions were similar: log “Watcher B fired!” and then change a third variable, `status_C`.
I did this one more time, setting up Watcher C to watch `status_C`. When `status_C` changed, Watcher C would log its message, “Watcher C fired!”, and that was the end of my planned chain for this little test.
It was pretty straightforward, really. Just making sure each watcher was looking at the right variable and triggered the next variable change correctly. Had to double-check the variable names a couple of times, easy to make a typo there.
Seeing it Run
Time for the test. All I needed to do was kick off the whole thing by changing `status_A` manually. So I did that. Just set `status_A` to ‘triggered’.
And then I watched the console output. It was actually quite satisfying to see it work exactly as planned:
- First, “Watcher A fired!” popped up.
- Almost immediately after, “Watcher B fired!” appeared.
- And right on cue, “Watcher C fired!” showed up.
Success! The dominoes fell just like they were supposed to. Each watch waited for its turn, triggered by the action of the previous one. No weird overlaps or missed steps.
So yeah, that was the practice. Nothing too complicated, just setting up a sequence of watches. It’s a neat little pattern, useful to understand how you can chain reactions together. Good exercise in managing state changes and their effects step-by-step. Got it working, saw the output, job done.
