[boost] Re: question regarding vacpp tests and mpl

From: Toon Knapen (toon.knapen_at_[hidden])
Date: 2004-07-26 08:02:27

Aleksey Gurtovoy wrote:

> Robert Ramey writes:
> 
>>The serialization library is failing all tests with IBM visual age compiler.
>>Errors occur within mpl.
> 
> 
> Not quite, I am afraid. Considering that the 'apply_if' test itself
> compiles without an error, this looks more like a problem with the
> particular context where the facility is used:
> 
> "/home/tk/boost_regression/boost/boost/serialization/level.hpp", line
> 44.9: 1540-0038 (S) The name "typename mpl::apply_if<
> boost::is_base_and_derived< boost::serialization::basic_traits,
> boost::serialization::nvp<A[9]> >,
> boost::serialization::implementation_level<
> boost::serialization::nvp<A[9]> >::traits_class_level<
> boost::serialization::nvp<A[9]> >, boost::mpl::int_<3> >::type" is
> not a type.
> 
> Looking at the code in "level.hpp", this is one complicated typedef!
> 
>     typedef
>         BOOST_DEDUCED_TYPENAME mpl::apply_if<
>             is_base_and_derived<basic_traits, T>,
>             traits_class_level<T>,
>         //else
>         BOOST_DEDUCED_TYPENAME mpl::apply_if<
>             is_fundamental<T>,
>             mpl::int_<primitive_type>,
>         //else
>         BOOST_DEDUCED_TYPENAME mpl::apply_if<
>             is_class<T>,
>             mpl::int_<object_class_info>,
>         //else
>         BOOST_DEDUCED_TYPENAME mpl::apply_if<
>             is_array<T>,
>             #if BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x564))
>                 mpl::int_<not_serializable>,
>             #else
>                 mpl::int_<object_serializable>,
>             #endif
>         //else
>         BOOST_DEDUCED_TYPENAME mpl::apply_if<
>             is_enum<T>,
>             #if BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x564))
>                 mpl::int_<not_serializable>,
>             #else
>                 mpl::int_<object_serializable>,
>             #endif
>         //else
>             mpl::int_<not_serializable>
>         >::type
>         >::type
>         >::type
>         >::type
>         >::type type;
> 
> 
> It's inefficient, too (you don't need all these '::type's except the
> very last one), but in any case: I think the most practical way to
> approach the error is to simplify the above to the bare minimum
> (ignoring the semantics for now), and see how the compiler reacts. For
> instance,
> 
> #if BOOST_WORKAROUND(__IBMCPP__, BOOST_TESTED_AT(600))
>     typedef
>         BOOST_DEDUCED_TYPENAME mpl::apply_if<
>             is_base_and_derived<basic_traits, T>,
>             traits_class_level<T>,
>             mpl::int_<object_serializable>
>             >::type type;
> #else
>     // original code ...
> 
> #endif
> 

I tried Aleksey's suggestion above and it seems to improve the situation
for the serialization lib on vacpp. I suggest to apply the suggested modif.

Sorry for the late response but I was on vacation.

Toon