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Expected unqualified identifier before "xor" token

Why does g ++ compiler say: error: expected unqualified-id before 'xor' token

class BigInteger{
public:
    unsigned *array;

    BigInteger xor(BigInteger bi){    // g++ indicates error this line
        BigInteger n;
        if(bi.array == (unsigned*)0){
            return n;
        }
        return n;
    }
};
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2 answers


xor

is an alternative token for ^

in C ++, you cannot use it as an identifier. Same for or

/ bitor

and and

/ bitand

( ||

, |

, &&

, and &

, respectively), and several others. They are essentially keywords like if

or for

.

Choose a different name for your function.



Complete list of alternative tokens (C ++ standard §2.12 Keywords, see section 6.2 Alternative tokens for collations):

  • and
  • and_eq
  • bitand
  • bitor
  • set
  • not
  • not_eq
  • or
  • or_eq
  • exclusive
  • xor_eq
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Moan. Yes, it is this one who chases your tail and then realizes "What?" and shake your heads.

Similarly in my case, I have a class definition that defines a class method:

List* xor(List* list)

And I get the error g ++: error: expected unqualified id before '^ token



Eventually, it turns out that xor is a synonym for ^ and as such cannot be a function name.

What's worse (in my case) is that this works great FINE on MS Windows in Visual Studio (in my case in 2010). And this is the code that has been developed with various versions of Visual Studio since 1999 (Visual Studio 6).

So now I need to rename the function and rebuild on Windows as well as g ++ on linux ... one of these issues gets bigger as you work on it.

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