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8166 :: Why other templates stop working if the T -> Option[T] converter defined?

• alexeypetrushin (orginal) [2021-06-28T09:43:45+02:00] view original

  The code works if the T -> Option[T] converter commented out

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• shirleyquirk (orginal) [2021-06-28T10:33:22+02:00] view original

  My guess is because it's turning map[T, S](s: openArray[T]; op: proc (x: T): S into map[T, R](self: Option[T]; callback: proc (input: T): R): Option[R]

  Works if you change pick to list.mapIt(it.field) which also happens to be more efficient, if that's important.

  But the lesson is really: don't use converters, crazy things like this happen

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• alexeypetrushin (orginal) [2021-06-28T11:11:45+02:00] view original

  Thanks, after your explanation I tried to limit the scope of converter, and it works.

  
  converter to_option*[T: object | tuple | int | float | bool](v: T): Option[T] =
    v.some
  Run

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