How to find objects that don't share certain values?

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- pandabear7413
- - Joined 9 May, 2021
  - 102 topics • 203 posts
- 1
- 27 Feb, 2022
- Quote
I have 2 object types, A and B, and both have an instance variable called matchID.

At certain points in the game, every B instance should be destroyed if there isn't an A instance whose matchID equals B.matchID.

Here’s my pseudocode:

- IF there is a B instance whose matchID instance variable does not equal the matchID instance variable of any A instances, THEN Destroy B instance

What’s a clean way to implement this with C3? I'm probably overthinking this but I cant come up with something elegant.

Thanks
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R0J0hound
- Joined 15 Jun, 2009
- 90 topics • 7,300 posts
2

27 Feb, 2022
Quote

Cleanest way I can come up with is to also add a Boolean variable to A and B, and do this:

A: set paired to false
B: set paired to false

for each A
B: matchID = A.matchID
pick B instance 0
-- A: set paired to true
-- B: set paired to true

A: [inverted] is paired
-- A: destroy

B: [inverted] is paired
-- B: destroy

- pandabear7413
- - Joined 9 May, 2021
  - 102 topics • 203 posts
- 1
- 1 Mar, 2022
- Quote
Thanks R0J0hound for the suggestion, similar to what I was thinking - but better!

I was curious if there was a way to use elegant pick logic to do this in a 1- or 2-line event. I've seen some beautiful code suggestions in these forums that I never would have come up with, mainly because my brain just doesn't think that way.
- R0J0hound
- - Joined 15 Jun, 2009
  - 90 topics • 7,300 posts
- 1
- 1 Mar, 2022
- Quote
I’m always trying to find ways to simplify the events if I can.

Another idea instead of the Booleans is to use a dictionary. I’ll call the dictionary “pairs”. Nice way to use less variables, probably faster for a large amount of objects. The only downside is it doesn’t handle if multiple A or multiple B have the same matchId. But that may not be an issue if that can’t happen.
for each A -- pairs: add key A.matchId with value A.uid for each B -- pairs: has key B.matchId -- -- pairs: remove key B.matchId -- else -- -- B: destroy pairs: for each key A: pick by uid pairs.curValue -- A: destroy -- pairs: remove key pairs.curKey