On Sun, Apr 02, 2017 at 01:18:58AM +0300, Ville Voutilainen wrote:
> Tested on Linux-x64.
>
> 2017-04-02 Ville Voutilainen <ville.voutilai...@gmail.com>
>
> Implement std::is_aggregate.
> * include/std/type_traits (is_aggregate): New.
> * testsuite/20_util/is_aggregate/requirements/explicit_instantiation.cc:
> New.
> * testsuite/20_util/is_aggregate/requirements/typedefs.cc: Likewise.
> * testsuite/20_util/is_aggregate/value.cc: Likewise.
>
> diff --git a/libstdc++-v3/include/std/type_traits
> b/libstdc++-v3/include/std/type_traits
> index 6707caa..89a3738 100644
> --- a/libstdc++-v3/include/std/type_traits
> +++ b/libstdc++-v3/include/std/type_traits
> @@ -3062,6 +3062,25 @@ template <typename _From, typename _To>
> #endif
> #undef _GLIBCXX_NO_BUILTIN_HAS_UNIQ_OBJ_REP
>
> +#ifdef __has_builtin
> +# if !__has_builtin(__is_aggregate)
> +// Try not to break non-GNU compilers that don't support the built-in:
> +# define _GLIBCXX_NO_BUILTIN_IS_AGGREGATE 1
> +# endif
> +#endif
> +
> +#ifndef _GLIBCXX_NO_BUILTIN_IS_AGGREGATE
> +#define __cpp_lib_is_aggregate 201703
> + /// is_aggregate
> + template<typename _Tp>
> + struct is_aggregate
> + : bool_constant<__is_aggregate(
> + remove_cv_t<_Tp>
> + )>
Any reason for the wrapping?
> + : bool_constant<__is_aggregate(remove_cv_t<_Tp>)>
Would fit on one line.
I admit I know next to nothing about libstdc++ code formatting.
> + { };
Also, shouldn't there be also:
/// is_aggregate_v
template<typename _Tp>
_GLIBCXX17_INLINE constexpr bool is_aggregate_v =
is_aggregate<_Tp>::value;
somewhere with appropriate guards (or within the same ones)?
> +#endif
> +#undef _GLIBCXX_NO_BUILTIN_IS_AGGREGATE
> +
> #endif // C++17
>
> _GLIBCXX_END_NAMESPACE_VERSION
I'm surprised tests for the is_*_v variable templates are only in
experimental/type_traits/value.cc when they are now apparently
part of C++17.
Jakub
