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3384 :: Problems with empty arrays

• cdome (orginal) [2017-11-30T16:25:32+01:00] view original

  I have the macro that produces const arrays, unfortunately when array comes out of macro as empty, it doesn't compile:

  const required_fields: array[0, tuple[f1: int, f2: string]] = []
  
  Run

  Compiler complains:

  Error: type mismatch: got (array[0..-1, empty]) but expected 'array[0..-1, tuple[f1: string, f2: stri
  ng]]'
  Run

  Any quick hack I can use to make it work?

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• Araq (orginal) [2017-11-30T16:50:18+01:00] view original

  Give us the definition of your macro please.

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• andrea (orginal) [2017-11-30T16:59:11+01:00] view original

  No need for the macro - the code does not compile even if written manually

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• cdome (orginal) [2017-11-30T17:25:36+01:00] view original

  I have shown the output of the macro. If array was written manually, I could simply remove the empty array as it is of no use. But this one is autogenerated.

  Also const can't be left without initializer. It doesn't compile, which make sense:

  const required_fields: array[0, tuple[f1: int, f2: string]]
  Run

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• Udiknedormin (orginal) [2017-12-02T09:52:14+01:00] view original

  Seems like a bug to me but it can be hacked quite easily:

  const required_fields: array[0, tuple[f1: int, f2: string]] =
    static(var a: array[0, tuple[f1: int, f2: string]]; a)
  Run

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• cdome (orginal) [2017-12-02T10:59:12+01:00] view original

  Thanks, didn't know that static can also be an expression. Nim is fun to deal with.

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• Udiknedormin (orginal) [2017-12-02T19:43:48+01:00] view original

  I don't remember who it was, but someone here on the forums complained about indentiation-based syntax as they preffered braces. The answer was using parentheses and semicolons, just like I did right now.

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