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13778 :: How do I destroy an object in Nim?

• warehouse_enjoyer (orginal) [2026-03-11T00:41:18+01:00] view original

  If I have something like:

  
  type Timer = object
    time: float = 0
    duration: float
  Run

  And I want to destroy the timer when time > duration, how would I do that?

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• darkestpigeon (orginal) [2026-03-11T01:11:04+01:00] view original

  What are you trying to do? Give more context, or an example in other programming language.

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• Ghazali (orginal) [2026-03-11T01:30:37+01:00] view original

  Most of time Nim's ARC or ORC is used in most of codes objects are destroyed automatically as soon as they are no longer needed.

  So You don't need to destroy them manually

  Stack Objects are will be destroyed automatically via a =destroy hook when the procedure returns.

  Heap Objects (ref object) it is destroyed when the last reference to it is removed settingvvalue holding to nil.

  
  type Timer = object
    time: float
    duration: float
  
  var timers: seq[Timer] = @[Timer(time: 0, duration: 5.0)]
  
  # To destroy expired one:
  for i in countdown(timers.high, 0):
    if timers[i].time > timers[i].duration:
      timers.delete(i) # This destroy the object ARC then calls =destroy no need to do it manually.
  Run

  You can also see when it get destroyed:

  
  proc `=destroy`(x: var Timer) =
    # This runs automatically
    echo "Timer resources being cleaned ..."
  Run

  Only If you are using raw pointers (like ptr Timer) and manual allocation via alloc, you must use dealloc to free the memory

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• morturo (orginal) [2026-03-11T01:56:12+01:00] view original

  
  proc drop[T](obj: sink T) =
    discard
  Run

  https://play.nim-lang.org/#pasty=FSLcHWGS

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• warehouse_enjoyer (orginal) [2026-03-11T12:00:46+01:00] view original

  I want to create multiple Timer objects and store them in an array or similar structure. Every frame, I'll iterarate over the structure and call some procedure for each timer present, for as long as time is not greater than duration. I don't want the program to continue storing/updating Timer objects once they've completed their duration, so I was asking for a way to prevent that. Though if I'm understanding @Ghazali correctly, the correct way to do this might be to just remove objects from the structure?

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• darkestpigeon (orginal) [2026-03-11T14:56:12+01:00] view original

  Unless you're doing manual memory management, you don't need to do anything to destroy objects in nim. They are destroyed automatically when they go out of scope (no longer reachable from the stack).

  In your case, you probably have some collection of timers you iterate over. All you need to do is to remove the unwanted timers from the collection.

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