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9215 :: Default values for type(object) fields

• TKD (orginal) [2022-06-07T17:09:42+02:00] view original

  I was just coding up an object that theoretically should have about 50 fields with well-defined initial values. Then, I found out that Nim does not support initial values for type (object) fields, e.g.,

  
  type
    Foo = object
      a: float = 11.0  # Error
      b: float = 0.001 # Error
      ...
      ...
  Run

  With 50 fields, I would have to list these in the type and then write a proc to initialise all 50 fields again.

  I am fine if this is a deliberate philosophical stance in Nim but I was just wondering what the technical reasons are for it.

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• Yardanico (orginal) [2022-06-07T17:13:28+02:00] view original

  The RFC about this is accepted, and there's a WIP PR by flywind already.

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• Zoom (orginal) [2022-06-07T17:14:07+02:00] view original

  See these RFCs:

  https://github.com/nim-lang/RFCs/issues/126 https://github.com/nim-lang/RFCs/issues/233 https://github.com/nim-lang/RFCs/issues/252

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• DeletedUser (orginal) [2022-06-07T17:19:12+02:00] view original

  See also https://github.com/beef331/constructor#defaults which supports default values for fields using macros.

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• TKD (orginal) [2022-06-07T17:22:37+02:00] view original

  Excellent. I will subscribe to the PR. Thanks.

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• TKD (orginal) [2022-06-07T17:46:15+02:00] view original

  Thanks for this. I will use this in the interim whilst the RFC is being worked on.

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• TKD (orginal) [2022-06-07T17:48:31+02:00] view original

  Thanks. These are very useful.

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