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13030 :: Setting bit flags with nim enum; C/C++ interop.

• xrfez1 (orginal) [2025-05-28T09:00:04+02:00] view original

  Is there a place in system/basic_types.nim for a bitwise or of an enum? A user can write the helper but should it already be there?

  
  template `or`(a, b: enum): typeof(a) =
    ## Bitwise `or` of enum types
    ## Returns the value as the first enum type.
    when typeof(a) isnot typeof(b):
      {.warning: "Bitwise `or` is unsafe for different enum types".}
    typeof(a)(ord(a) or ord(b))
  Run

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• Araq (orginal) [2025-05-28T09:35:10+02:00] view original

  Instead map the enum to the "proper" values (aka their log2 values) and use set[TheEnum] on the Nim side. That might not always be possible though and then you're better off with a distinct intT with an or operator.

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• xrfez1 (orginal) [2025-05-28T10:15:23+02:00] view original

  No place. Fair enough.

  Most wrappers I see map C enums to HolyEnums and I feel like I have to jump through hoops to send a bit flag back.

  Ill think on your suggestions.

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