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12755 :: Object Variant - no variable in one variant

• fryorcraken (orginal) [2025-04-01T05:49:17+02:00] view original

  Hi,

  I am using object variant and one variant below does not need any variable:

  
  type
    NodeKind = enum
      nkInt,
      nkNil        # a leaf with no value
    Node = ref NodeObj
    NodeObj = object
      case kind: NodeKind
      of nkInt: intVal: int
      of nkNil: # no var needed
  Run

  Is it possible to do?

  Above returns

  
  Error: identifier expected, but got 'keyword of'
  Run

  If I remove the line:

  
      case kind: NodeKind
      of nkInt: intVal: int
  Run

  
  Error:  not all cases are covered; missing: ...
  Run

  I tried to just declare a nil var using type type(nil) but it did not work out either

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• PMunch (orginal) [2025-04-01T07:14:33+02:00] view original

  You need to use discard:

  
  type
    NodeKind = enum
      nkInt,
      nkNil        # a leaf with no value
    Node = ref NodeObj
    NodeObj = object
      case kind: NodeKind
      of nkInt: intVal: int
      of nkNil: discard
  Run

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• xigoi (orginal) [2025-04-02T23:45:28+02:00] view original

  To be honest, I don’t like this C++-style nonsensical keyword overloading.

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• Araq (orginal) [2025-04-03T01:58:31+02:00] view original

  It used to be nil, believe it or not.

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