Logical XOR operator

Introduction

Occasionally I come to a need of a logical xor operator (^^) that, obviously, doesn't exist in C++. However, it can be rather easily implemented.

Code listing

#define log_xor || log_xor_helper() ||


struct log_xor_helper {
    bool value;
};

template<typename LEFT>
log_xor_helper &operator ||(const LEFT &left, log_xor_helper &xor) {
    xor.value = (bool)left;
    return xor;
}

template<typename RIGHT>
bool operator ||(const log_xor_helper &xor, const RIGHT &right) {
    return xor.value ^ (bool)right;
}

Examples

0 log_xor 0 == false
0 log_xor 5 == true
8 log_xor 0 == true
8 log_xor 5 == false

Other details

• Although they don't have to have the same type, operands should be castable into a simple boolean.
• Precedence of log_xor operator is the same as logical or's (||) one.
• If you decide to use it, I suggest you to add log_xor keyword to the usertype.dat file and insert somewhere the #pragma warning(disable: 4800) line.

This article has no explicit license attached to it but may contain usage terms in the article text or the download files themselves. If in doubt please contact the author via the discussion board below.

A list of licenses authors might use can be found here