Re: [Boost-users] [logic] boost::logical_xor

Subject: Re: [Boost-users] [logic] boost::logical_xor
From: Roman Perepelitsa (roman.perepelitsa_at_[hidden])
Date: 2010-08-13 07:11:31

2010/8/12 gast128 <gast128_at_[hidden]>

> > Hello all,
> > small question: there seems no xor operator in c++ but there is also no
> Boost
> > xor functor (like the std::logical_and)?
> > Scenario: I have 2 data members used in variant like way: only 1 may be
> valid.
> > Both valid or both invalid is incorrect.
> >
> > Can't you use !!A != !!B? (or !!A ^ !!B)
>
> ah quite brilliant! I was thinking about the (a ? !b : b). Still a
> logical_xor
> does also has a documentation value.

operator^ works fine for booleans, and I guess that's what you want to apply
logical_xor to.

bool a, b;
bool c = a ^ b;  // Fine.

Roman Perepelitsa.