is_gather_signature.h

/*  This file is part of the Vc library. {{{
Copyright © 2014 Matthias Kretz <kretz@kde.org>
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}}}*/

template <std::size_t, typename... Args> struct is_gather_signature_impl;
template <std::size_t N_, typename Arg0, typename Arg1, typename... MoreArguments>
struct is_gather_signature_impl<N_, Arg0, Arg1, MoreArguments...>
    : public std::integral_constant<bool, has_subscript_operator<Arg0>::value &&
                                              !is_loadstoreflag_internal<Arg1>::value &&
                                              has_subscript_operator<Arg1>::value> {
};
template<typename... Args> struct is_gather_signature_impl<0, Args...> : public std::false_type {};
template<typename... Args> struct is_gather_signature_impl<1, Args...> : public std::false_type {};

template <typename... Args> struct is_gather_signature : public is_gather_signature_impl<sizeof...(Args), decay<Args>...> {};