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1381 :: Noob question - adding to seq in objects

• Swend (orginal) [2015-06-29T11:31:19+02:00] view original

  I'm having what seems to be a very simple problem that I simply can't figure out. I have an object containing a seq. If I try to add to that seq I get:

  "Error: type mismatch: got (seq[SomeType], SomeType) [...] but expected one of: [...] system.add(x: var seq[T], y: T)"

  So I try to change it to 'var seq[SomeType]', but then get:

  "Error: invalid type: 'var seq[SomeType]' in this context: 'SomeObject'"

  Is there no way to have variable sequences in objects?

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• andrea (orginal) [2015-06-29T11:45:41+02:00] view original

  It would be more clear if you posted exactly what you are trying to do (code included), but I think that in this case you are declaring the object like this let obj = ..., which makes it immutable, while you would need var obj = ...

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• Swend (orginal) [2015-06-29T12:54:14+02:00] view original

  Okay, the code looks something like this.

  type
    SomeObject = object
      s: (var) seq[SomeType]
  
  var
    obj = SomeObject(s: @[])
  
  proc someProc(o: SomeObject, a: SomeType) =
    o.s.add(a)

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• def (orginal) [2015-06-29T13:02:42+02:00] view original

  What's missing is the var in the someProc proc definition:

  type
    SomeType = object
    SomeObject = object
      s: seq[SomeType]
  
  var
    obj = SomeObject(s: @[])
  
  proc someProc(o: var SomeObject, a: SomeType) =
    o.s.add(a)
  Run

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• Swend (orginal) [2015-06-29T13:08:09+02:00] view original

  Wow, I knew it would be something simple like that. Thanks a lot :D

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