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4015 :: Rust style enums. How?

• playX (orginal) [2018-07-04T21:51:56+02:00] view original

  Hello everyone! I want to convert that code to Nim but i don't know how :(

  
  enum Opcode {
          Push(i64),
           Add,
          PopN(usize),
  }
  Run

  Any ideas?

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• dom96 (orginal) [2018-07-04T22:22:14+02:00] view original

  Something like this:

  type
    OpcodeKind = enum
      Push, Add, PopN
    
    Opcode = object
      case kind: OpcodeKind
      of Push:
        i: int64
      of Add:
        discard
      of PopN:
        u: uint
  
  
  Run

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• mashingan (orginal) [2018-07-05T02:47:27+02:00] view original

  and that's know as object variant so if later someone say just use object variant , you can refer to @dom's code ;)

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• playX (orginal) [2018-07-05T07:57:15+02:00] view original

  Thanks!

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• Araq (orginal) [2018-07-05T08:17:06+02:00] view original

  There is also https://github.com/andreaferretti/patty

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• cumulonimbus (orginal) [2018-07-05T11:27:30+02:00] view original

  Related: @dom96's example uses "discard" to mark "nothing here", whereas the patty documentation (from @Araq's link) uses "nil"; Is there a difference? Is there a blessed way?

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• DeletedUser (orginal) [2018-07-05T18:29:49+02:00] view original

  There is no difference, except discard is easier to understand in my opinion

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• gudmundv (orginal) [2018-07-05T22:12:37+02:00] view original

  (as someone not familiar with the language), I'm curious if it would be possible to get a nicer syntax for these through macros?

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• dom96 (orginal) [2018-07-05T23:03:14+02:00] view original

  Welcome to Nim :)

  I'm curious if it would be possible to get a nicer syntax for these through macros?

  Yep, it's possible. The patty package provides this:

  https://github.com/andreaferretti/patty#constructing-variant-objects

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• gudmundv (orginal) [2018-07-06T01:41:12+02:00] view original

  Awesome

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