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5616 :: Returning a `var` inside of a tuple

• iocat (orginal) [2019-11-30T02:04:06+01:00] view original

  Hi folks!

  So I had the following proc signature

  proc insertsOrUpdates*[K, V](rbt: RedBlackTree[K, V], key: K, value: V): tuple[
      inserted: bool, value: var V]
  Run

  .

  But it seems the returned value inside of the tuple wasn't functioning. Is this a valid syntax? Did an echo repr against the returned tuple. Here's what it prints: [Field0 = false, Field1 = (invalid data!)]

  Thanks!

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• mratsim (orginal) [2019-11-30T10:42:23+01:00] view original

  I think the whole tuple needs to be var.

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• iocat (orginal) [2019-11-30T11:20:40+01:00] view original

  Thanks for replying.

  Sorry but that's kinda not what I intended the function to return :(. Because I don't have a lvalue for "inserted" part of the tuple so that it can fit in into a var. Right (?)

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• Araq (orginal) [2019-11-30T13:32:40+01:00] view original

  The signature is weird anyway, how about:

  proc insertsOrUpdates*[K, V](rbt: RedBlackTree[K, V], key: K, value: var V): bool
  Run

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• cumulonimbus (orginal) [2019-11-30T14:15:19+01:00] view original

  ... and, not entirely related to your question, but in some circles this operation is referred to as an "upsert" (update-or-insert)

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