- template<class F>
- auto then(F continuation)
- -> typename std::enable_if<
- is_future<decltype(continuation(std::move(*this)))>::value,
- decltype(continuation(std::move(*this)))
- >::type
+ template <class F>
+ auto then(F continuation) -> typename std::enable_if_t<is_future<decltype(continuation(std::move(*this)))>::value,
+ decltype(continuation(std::move(*this)))>