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

Subject: Re: [Boost-users] [range_ex] range_ex conflicts with non_copyable
From: Thorsten Ottosen (thorsten.ottosen_at_[hidden])
Date: 2009-04-05 16:52:38

041021042 skrev:
> Hi，
> 
> The following code works well with old version of range_ex (Dec 2008), but when I update range_ex to an newer version (after Feb 2009), the code cannot compile.
> 
> code:
> #include <boost/range/algorithm.hpp>
> #include <boost/ptr_container/ptr_vector.hpp>
> 
> 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 &)'
> 

Perhaps the argument of find() is taken by value? I guess we should use 
const T& here.

-Thorsten