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9546 :: How to instantiate a `DateTime` object at compile time?

• Isofruit (orginal) [2022-10-24T21:35:39+02:00] view original

  I asked the same question on [stackOverflow]https://stackoverflow.com/questions/74185889/how-to-instantiate-a-datetime-object-at-compile-time):

  I'm pretty sure at this point I'm just overlooking something obvious. Anyway, Nim 2 will have the ability to instantiate objects with default values for its fields. The feature is already available on nim's devel branch. Given that, I would like to be able to have this default instantiation for fields with DateTime types.

  Something like this:

  import std/times
  
  type A = object
    d: DateTime = times.now()
  
  let x = default(d)
  Run

  However, this can not work, as now() can not work at compiletime. Similarly, dateTime and initDateTime break at compiletime.

  It is unlikely that the actual value will ever be used, I just need a way to instantiate objects so that other packages can replace the values later on (e.g. norm when parsing data from a database into that object). Given that, how can I instantiate a DateTime to make objects with such fields default initializable?

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