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1568 :: Error: 'object' is not a concrete type.

• Stefan_Salewski (orginal) [2015-08-22T23:00:43+02:00] view original

  I was just going to remove some dummy types from my gtk3 module, simple to remove clutter and save some lines... For example, AccelGroupPrivateObj is an opaque dummy type, field priv1 is not exported, so I thought just to replace it with a plain object, see below. I am surprised by the compiler error message. So what to do? Define one single dummy object type and use that for all the priv filelds?

  type
    GObjectObj{.inheritable.} = object
      i: int
  
  type
    AccelGroupPrivateObj = object
    
    AccelGroup* =  ptr AccelGroupObj
    AccelGroupPtr* = ptr AccelGroupObj
    AccelGroupObj*{.final.} = object of GObjectObj
      priv1: ptr AccelGroupPrivateObj
  
  type
    #AccelGroupPrivateObj = object
    XAccelGroup* =  ptr XAccelGroupObj
    XAccelGroupPtr* = ptr XAccelGroupObj
    XAccelGroupObj*{.final.} = object of GObjectObj
      priv1: ptr object
  Run

  t.nim(18, 5) Error: 'object' is not a concrete type.

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• Araq (orginal) [2015-08-23T00:46:53+02:00] view original

  object is a nominal type construction, so you need to give it a name. Otherwise it's considered a type-class and thus it's "not concrete". For your purposes just use pointer instead of ptr object.

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• Stefan_Salewski (orginal) [2015-08-23T00:56:30+02:00] view original

  OK, thanks.

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• nimluckybull (orginal) [2015-08-25T10:33:18+02:00] view original

  type ClassA{.inheritable.} = object i: int type ClassB = object ptrClassSon* = ptr ClassSon ClassSon*{.final.} = object of ClassA ptrClassB: ptr ClassB type ptrClassSon2* = ptr ClassSon2 myPtrObj = ptr object # Look at here ClassSon2*{.final.} = object of ClassA ptrClassB: myPtrObj #OK #ptr RootObj #OK #pointer #OK #ptr object #Error

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• Araq (orginal) [2015-08-25T13:51:24+02:00] view original

  Well yes, this is the expected behaviour. Objects need a name, otherwise it's a type-class.

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