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5942 :: unable to deference pointer and assign? Nim 1.0.6

• lotzz (orginal) [2020-02-17T23:20:27+01:00] view original

  So I'm just messing around and from what I understand this code should be fine, but for some reason I'm getting an error. I am wondering if there is something I don't understand about pointers in Nim and how to use them

  proc newLead[T](oldData:T):Lead =
      #copy the data if the old data is not mutable
      result.desc = T.name
      result.data = alloc0(sizeof(T))
      result.data[] = 10 #THIS is where im getting the error at the `=`, also here we are assuming T == int
      echo result.data.repr
      dealloc(result.data) ##this is just to clean up because im testing
  Run

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• DeletedUser (orginal) [2020-02-17T23:38:04+01:00] view original

  The type of alloc0 is pointer, you cannot assign to these directly. You need to cast it to ptr int to assign int to it. So cast[ptr int](result.data)[] = 10

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• lotzz (orginal) [2020-02-18T01:02:44+01:00] view original

  ah thank you so much

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