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12900 :: Is this a bug when using pragma "requiresInit" ?

• beyonddd (orginal) [2025-05-10T19:09:25+02:00] view original

  Hi folks, Im a newcomer here and today is the second day of using Nim. Everything is great so far, but i encounter something weird when using pragma {.requiresInit.}. Here's the code.

  
  
  type
      EntityId = distinct int
      Entity = object
          id {.requiresInit.} : EntityId
          name: string
          transformId = ComponentId(-1)
          rectangleDataId = ComponentId(-1)
  var
      entities: seq[Entity]
  
  proc findEntityById(id: EntityId): Entity =
      for e in entities:
          if e.id == id:
              return e
  Run

  The loop generate this error message, and if i remove the {.reqiuresInit.} pragma, the code compiled.

  Error: The Entity type requires the following fields to be initialized: id.

  im looking for an explanation why is this happen and solution to work around this without removing the pragma.

  Thank you in advance !

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