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1828 :: named booleans

• ephja (orginal) [2015-11-26T11:53:00+01:00] view original

  What do you think about this construct? I do find it useful

  template genNamedBoolType*(name, field: expr, exportType = true): stmt =
      when exportType:
          type
              name* = object
                  field*: bool
      else:
          type
              name = object
                  field*: bool
      
      converter `to name`*(yes: bool): name =
          result = name(field: yes)
  
  genNamedBoolType DidFail, didFail
  
  proc doStuff(): DidFail =
      result = false
  
  if doStuff().didFail:
      discard
  Run

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• Araq (orginal) [2015-11-26T12:35:45+01:00] view original

  Hrm, did you just reinvent enum?

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• ephja (orginal) [2015-11-26T14:44:30+01:00] view original

  A restricted form perhaps, with a more concise usage, if you take case coverage into consideration.

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• Jehan (orginal) [2015-11-26T14:48:50+01:00] view original

  I am not sure if the (relative) conciseness is an advantage; will you be able to easily understand code that you wrote months ago if you first have to decipher the semantics of the type (especially if a converter is involved and implicit stuff is going on under the hood)?

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• ephja (orginal) [2015-11-26T15:00:41+01:00] view original

  I think so, if the name actually indicates that it's a bool

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