Re: [Boost-users] [mpl] cross product and gcc specific compiler error

Subject: Re: [Boost-users] [mpl] cross product and gcc specific compiler error
From: Steven Watanabe (watanabesj_at_[hidden])
Date: 2012-05-14 09:02:09

AMDG

On 05/13/2012 04:45 PM, Josh Quigley wrote:
>  Hi,
> 
>  I grabbed an mpl cross product implementation (product_view) of this
>  mailing list. It works fine in MSVC but fails in gcc:
> 

It doesn't work because you're relying on
implementation details.  Use boost::mpl::at_c<XXX, 0>::type
instead of XXX::item0.

> <snip>
> BOOST_AUTO_TEST_CASE_TEMPLATE(MyTest, DecimalIntegralT,
> EachDecimalWithEachIntegralT)
> {
>     {
>         typename DecimalIntegralT::item1 r(1234567);   // Fails on
> gcc: no type named ‘item0’ in ‘struct boost::mpl::v_item<long long
> unsigned int, boost::mpl::v_item<ext::decimal::decimal128,
> boost::mpl::vector0<mpl_::na>, 0>, 0>
>         typename DecimalIntegralT::item0 d(r);
> 
>         BOOST_CHECK_EQUAL(static_cast<long long>(d), r);
>     }
> }
> 
> 

In Christ,
Steven Watanabe