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8241 :: Base method when returning an iterator

• rtrn (orginal) [2021-07-18T11:11:10+02:00] view original

  I'm pretty much a beginner

  method fetchDataInterval(self : dbHandle): iterator {.base.} =
      return iterator (): coldata =
          for i in self.db.fastRows(sql(self.fetchstring)):
              yield i.mapIt(parseInt(it))
  Run

  I get a warning

  Warning: generic methods are deprecated [Deprecated]

  Warning: use {.base.} for base methods; baseless methods are deprecated [UseBase]

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• rtrn (orginal) [2021-07-18T12:18:30+02:00] view original

  Ok, by changing method to proc fixes the problem.

  Is this something about proc vs method ?

  static vs dynamic dispatch ?

  https://matthiashager.com/proc-method-nim

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• ynfle (orginal) [2021-07-18T13:54:30+02:00] view original

  See this example https://play.nim-lang.org/#ix=3tlq. The warning comes from the fact that the return type is a generic iterator. If you change the return type to an iterator that returns coldata then the warning isn't issued, ie. the warning is only issued on the second getIter method (you can check this by clicking on the debug button)

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