Re: [Boost-users] phoenix function problem

Subject: Re: [Boost-users] phoenix function problem
From: Joel de Guzman (joel_at_[hidden])
Date: 2010-04-23 01:58:08

On 4/23/2010 1:49 AM, Olaf Peter wrote:
> Hi,
>
> in the example attached, the 1st test case fails on runtime:
>
> test_phoenix_fcn.cpp(105): test 'at_c<0>( rlc )&&  at_c<1>( rlc )&&
> at_c<2>( rlc )' failed in function 'int main(int, char**)'
> test_phoenix_fcn:
> /home/olaf/Projects/programming/cpp/boost/trunk/boost/optional/optional.hpp:591:
> typename boost::optional_detail::optional_base<T>::reference_type
> boost::optional<T>::get() [with T = double]: Assertion
> `this->is_initialized()' failed.
> Aborted
>
>
> the 2nd (with defined WANT_TO_HAVE) doesn't compile. This is the goal.
>
> Where is my misunderstanding here? To to get it working correctly?

Your operator()s are wrong (C++ error, unrelated to phoenix).
Try this:

#if WANT_TO_HAVE
     template <typename T, typename ID>
     struct result { typedef vector_type type; };

     vector_type operator()( const vector_type& v, rlc ) const
     {
         return fusion::as_nview<0, 1, 2>( v );
     }

     vector_type operator()( const vector_type& v, lcr ) const
     {
         return fusion::as_nview<2, 0, 1>( v );
     }

#else

Regards,
-- 
Joel de Guzman
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