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6322 :: Q: An object variant case with no field?

• snej (orginal) [2020-05-12T20:20:53+02:00] view original

  I'm implementing a variant object type, where one of the enum cases has no fields associated with it, but get a syntax error:

  type
      AuthenticatorType = enum
          None,
          Basic,
          Session,
          Cookie
      Authenticator = object
          case type: AuthenticatorType:
              of None:
  # Error: identifier expected, but got 'keyword of'
              of Basic:   username, password: string
              of Session: sessionID: string
              of Cookie:  name, value: string
  Run

  What can I put after of None: to satisfy the parser? Or is it impossible to have a case with no associated value?

  (I've checked the manual but it says nothing about this possibility.)

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• doofenstein (orginal) [2020-05-12T20:26:09+02:00] view original

  it works this way:

  type
      AuthenticatorType = enum
          None,
          Basic,
          Session,
          Cookie
      Authenticator = object
          case type: AuthenticatorType:
              of None: discard
              of Basic:   username, password: string
              of Session: sessionID: string
              of Cookie:  name, value: string
  Run

  you can't just let of None: dangle around, you need to add a discard

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