what is the advantage of using negative enums

Posted by Naveen on Stack Overflow See other posts from Stack Overflow or by Naveen
Published on 2010-04-26T03:06:39Z Indexed on 2010/04/26 3:13 UTC
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enums

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In the kaleidoscope parser / AST example at LLVM, the enum is given all negative values. Why the minus sign ?

enum Token {
  tok_eof = -1,
  // commands
  tok_def = -2, tok_extern = -3,
  // primary
  tok_identifier = -4, tok_number = -5
};

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