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287 :: Any reason recursive or multi-level generics shouldn't work?

• MFlamer (orginal) [2013-10-22T17:24:48+02:00] view original

  The following code seems to confuse the compiler.

  
  import typetraits
  
  type
    TFix[T] = distinct T
  
  var t0 = cast[TFix[TFix[int]]](10)
  var t1 = cast[TFix[TFix[float]]](69.69)
  
  echo(t0.type.name)
  echo(t1.type.name)
  Run

  The following types are echoed.....

  TFix[TFix[int]]

  TFix[TFix[int]]

  The second should be TFix[TFix[float]]

  I have already filed a bug for this. I'm wondering if any of the experts(Zahary :-)) have any comments on this. Should the compiler be able to support this?

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• Araq (orginal) [2013-10-22T20:00:00+02:00] view original

  Should the compiler be able to support this?

  It doesn't make too much sense, but it should be allowed for generic programming.

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• MFlamer (orginal) [2013-10-23T00:32:40+02:00] view original

  In this case it doesn't seem to make much sense, but I have a few ideas for how it might be useful.

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• MFlamer (orginal) [2013-10-23T01:43:24+02:00] view original

  This should be working for the actors lib also.

  
    TActor[TIn, TOut] = object{.pure, final.}
      i: TChannel[TTask[TIn, TOut]]
      t: TThread[ptr TActor[TIn, TOut]]
  Run

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