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12763 :: A quickie object identifer?

• forkbomb (orginal) [2025-04-03T01:45:21+02:00] view original

  I implemented a deep copy for an object, and trying to test it.

  Feels like repr used to emit something unique, but no longer.

  Some fast googlin' hasn't helped me, so I reach out to you, the fine Nim community.

  Is there some sort of object identifier I can access easily for something like:

  
  var original = new AmazingObject
  var copied   = original.copy
  
  assert original.id != copied.id
  Run

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• forkbomb (orginal) [2025-04-03T01:54:43+02:00] view original

  ......... I guess I can just modify the original and test against that.

  Question remains otherwise.

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• janAkali (orginal) [2025-04-03T08:38:52+02:00] view original

  If I get this right, you can compare addresses:

  
  type
    Foo = ref object
      id: int
  
  var foo = Foo()
  var foobar = foo
  var bar = foo.id
  
  echo cast[int64](foo.id.addr)    # 139738486407248
  echo cast[int64](foobar.id.addr) # 139738486407248
  echo cast[int64](bar.addr)       # 4272560
  Run

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• Araq (orginal) [2025-04-03T11:08:58+02:00] view original

  No, as these are all ref their true identity is just cast[int](foo) etc.

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• PMunch (orginal) [2025-04-03T14:07:14+02:00] view original

  However if you want to debug a deep copy implementation you should traverse the whole object and check all ptr/ref instances. You can simply collect them and hash them into a single id though.

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• forkbomb (orginal) [2025-04-03T19:05:39+02:00] view original

  Good to go, thanks for the responses all.

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