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#pragma once

#include <type_traits>
#include <tuple>

namespace mbgl {

template <class...>
class TypeList {};

namespace detail {

template <class, class>
struct TypeCons;

template <class T, class... Ts>
struct TypeCons<T, TypeList<Ts...>> {
    using Type = TypeList<T, Ts...>;
};

template <class, template <class> class>
struct TypeFilter;

template <template <class> class Predicate>
struct TypeFilter<TypeList<>, Predicate> {
    using Type = TypeList<>;
};

template <template <class> class Predicate, class T, class... Ts>
struct TypeFilter<TypeList<T, Ts...>, Predicate> {
    using Tail = typename TypeFilter<TypeList<Ts...>, Predicate>::Type;
    using Type = std::conditional_t<Predicate<T>::value, typename TypeCons<T, Tail>::Type, Tail>;
};

} // namespace detail

template <class TypeList, template <class> class Predicate>
using FilteredTypeList = typename detail::TypeFilter<TypeList, Predicate>::Type;

} // namespace mbgl