Ren'Py, the DSE, and How Events Work

So, I have mentioned in the past that programming is hard.

What a surprise, right?

Well, today's bit of weirdness comes from the way the DSE framework in Ren'Py handles events, the way it processes those events, and the way that it determines when to execute an event.

So here was my issue: When setting up the core events for my game, I came across a truly strange interaction where the game began to execute a specific event, despite the fact that it was in neither the correct location, nor the correct time, or even the correct day within the game.

My first instinct was that maybe it was a typo. I was visiting the laboratory, but for some reason one of the character's generic events was playing out that occurred in the library! So maybe I'd just made a spelling error in the event.

Turns out it wasn't so simple. Or rather, it was simple, but not in the way I had expected.

After turning it over and over, I finally managed to hammer down what was going on, and in the process learned something about how it processes variables.

See, here's what the event code looked like:  

$ event("cyn_base_library", "act == 'library', tod == '3', dow == '3'", event.only(), priority=175)

$ event("cyn_base_library", "act == 'library', tod == '1', dow == '1'", event.only(), priority=175)

$ event("cyn_base_library", "act == 'library', tod == '1', dow == '7'", event.only(), priority=175)

$ event("cyn_base_garden", "act == 'garden', tod == '3', dow == '2', day >= '5', cyn_rel >= '1'", event.only(), priority=175)

$ event("cyn_base_garden", "act == 'garden', tod == '3', dow == '6', cyn_rel >= '1'", event.only(), priority=175)

$ event("cyn_base_lab", "act == 'laboratory', tod == '4', dow == '4', cyn_rel >= '1'", event.only(), priority=175)

Turns out, what I was doing was totally wrong, because none of those conditions was actually causing the event to play. What I should have typed was this:

$ event("cyn_base_library", "act == 'library' and tod == '3' and dow == '3'", event.only(), priority=175)
$ event("cyn_base_library", "act == 'library' and tod == '1' and dow == '1'", event.only(), priority=175)
$ event("cyn_base_library", "act == 'library' and tod == '1' and dow == '7'", event.only(), priority=175)
$ event("cyn_base_garden", "act == 'garden' and tod == '3' and dow == '2' and day >= '5' and cyn_rel >= '1'", event.only(), priority=175)
$ event("cyn_base_garden", "act == 'garden' and tod == '3' and dow == '6' and cyn_rel >= '1'", event.only(), priority=175)
$ event("cyn_base_lab", "act == 'laboratory' and tod == '4' and dow == '4' and cyn_rel >= '1'", event.only(), priority=175)

Instead of triggering the events when all of the conditions were met, it seemed more than happy to select the events based on their priority, totally ignoring the variable block.

All because I didn't use the word 'and' to separate my variables.

Hopefully someone finds this useful someday. In the meantime, it's back to the grind with me. There's so much work left to do, but this seemed like one of those major things that was really just a minor thing. Really though, I felt proud when I figured it out on my own, and without needing to consult the Internet for help.

**EDIT**

I AM AN IDIOT AND YOU SHOULD IGNORE THAT STUFF ABOVE BECAUSE IT'S STILL WRONG.

So after spending almost literally my entire night, here's the way the code blocks should really look:

    

$ event("cyn_base_library", "act == 'library'", event.only(), "tod == 3", "dow == 3", priority=175)
$ event("cyn_base_library", "act == 'library'", event.only(), "tod == 1", "dow == 1", priority=175)
$ event("cyn_base_library", "act == 'library'", event.only(), "tod == 1", "dow == 7", priority=175)
$ event("cyn_base_garden", "act == 'garden'", event.only(), "tod == 3", "dow == 2", "day >= 5", "cyn_rel >= 1", priority=175)
$ event("cyn_base_garden", "act == 'garden'", event.only(), "tod == 3", "dow == 6", "cyn_rel >= 1", priority=175)
$ event("cyn_base_lab", "act == 'laboratory'", event.only(), "tod == 4", "dow == 4", "cyn_rel >= 1", priority=175)

You will note that the variables have been moved outside of the second block. It's because the 'and' statement may or may not work. But it probably won't, so don't use it in that context.

LESSONS CONTINUE TO BE LEARNED!