Re: [Boost-users] [range_ex] range_ex conflicts with non_copyable

Subject: Re: [Boost-users] [range_ex] range_ex conflicts with non_copyable
From: Roman Perepelitsa (roman.perepelitsa_at_[hidden])
Date: 2009-04-06 03:31:27

2009/4/5 Igor R <boost.lists_at_[hidden]>

> > struct A : boost::noncopyable {
> >    int a;
> >    A(int _a) : a(_a) {}
> >    bool operator == (const A& r) const { return a == r.a; }
> > };
> >
> > int main()
> > {
> >    boost::ptr_vector<A> pva;
> >    A a(0);
> >    std::find(pva.begin(), pva.end(), a);  // ok
> >    boost::find(pva, a);   // cause an error
> > }
> >
> > compiler: msvc2008
> >
> > error message:
> > e:\zxg\boost\range_ex\range.cpp(8) : error C2248:
> 'boost::noncopyable_::noncopyable::noncopyable' : cannot access private
> member declared in class 'boost::noncopyable_::noncopyable'
> >        d:\software\boost_1_37_0\boost\noncopyable.hpp(27) : see
> declaration of 'boost::noncopyable_::noncopyable::noncopyable'
> >        d:\software\boost_1_37_0\boost\noncopyable.hpp(22) : see
> declaration of 'boost::noncopyable_::noncopyable'
> >        This diagnostic occurred in the compiler generated function
> 'A::A(const A &)'
>
> What's the benefit of providing assignment operator but blocking the
> copy-constructor?

There is no assignment operator in the provided code snippet.

Roman Perepelitsa.