} // namespace futures
+/**
+ Make a completed SemiFuture by moving in a value. e.g.
+
+ string foo = "foo";
+ auto f = makeSemiFuture(std::move(foo));
+
+ or
+
+ auto f = makeSemiFuture<string>("foo");
+*/
+template <class T>
+SemiFuture<typename std::decay<T>::type> makeSemiFuture(T&& t);
+
+/** Make a completed void SemiFuture. */
+SemiFuture<Unit> makeSemiFuture();
+
+/**
+ Make a SemiFuture by executing a function.
+
+ If the function returns a value of type T, makeSemiFutureWith
+ returns a completed SemiFuture<T>, capturing the value returned
+ by the function.
+
+ If the function returns a SemiFuture<T> already, makeSemiFutureWith
+ returns just that.
+
+ Either way, if the function throws, a failed Future is
+ returned that captures the exception.
+*/
+
+// makeSemiFutureWith(SemiFuture<T>()) -> SemiFuture<T>
+template <class F>
+typename std::enable_if<isSemiFuture<typename std::result_of<F()>::type>::value,
+ typename std::result_of<F()>::type>::type
+makeSemiFutureWith(F&& func);
+
+// makeSemiFutureWith(T()) -> SemiFuture<T>
+// makeSemiFutureWith(void()) -> SemiFuture<Unit>
+template <class F>
+typename std::enable_if<
+ !(isSemiFuture<typename std::result_of<F()>::type>::value),
+ SemiFuture<typename Unit::Lift<typename std::result_of<F()>::type>::type>>::type
+makeSemiFutureWith(F&& func);
+
+/// Make a failed Future from an exception_ptr.
+/// Because the Future's type cannot be inferred you have to specify it, e.g.
+///
+/// auto f = makeSemiFuture<string>(std::current_exception());
+template <class T>
+FOLLY_DEPRECATED("use makeSemiFuture(exception_wrapper)")
+SemiFuture<T> makeSemiFuture(std::exception_ptr const& e);
+
+/// Make a failed SemiFuture from an exception_wrapper.
+template <class T>
+SemiFuture<T> makeSemiFuture(exception_wrapper ew);
+
+/** Make a SemiFuture from an exception type E that can be passed to
+ std::make_exception_ptr(). */
+template <class T, class E>
+typename std::enable_if<std::is_base_of<std::exception, E>::value,
+ SemiFuture<T>>::type
+makeSemiFuture(E const& e);
+
+/** Make a Future out of a Try */
+template <class T>
+SemiFuture<T> makeSemiFuture(Try<T>&& t);
+
/**
Make a completed Future by moving in a value. e.g.
class Result = typename futures::detail::resultOf<F, ItT&&>::value_type>
std::vector<Future<Result>> window(Collection input, F func, size_t n);
+template <
+ class Collection,
+ class F,
+ class ItT = typename std::iterator_traits<
+ typename Collection::iterator>::value_type,
+ class Result = typename futures::detail::resultOf<F, ItT&&>::value_type>
+std::vector<Future<Result>>
+window(Executor* executor, Collection input, F func, size_t n);
+
template <typename F, typename T, typename ItT>
using MaybeTryArg = typename std::conditional<
futures::detail::callableWith<F, T&&, Try<ItT>&&>::value,
std::forward<T>(initial),
std::forward<F>(func));
}
-
-namespace futures {
-
-/**
- * retrying
- *
- * Given a policy and a future-factory, creates futures according to the
- * policy.
- *
- * The policy must be moveable - retrying will move it a lot - and callable of
- * either of the two forms:
- * - Future<bool>(size_t, exception_wrapper)
- * - bool(size_t, exception_wrapper)
- * Internally, the latter is transformed into the former in the obvious way.
- * The first parameter is the attempt number of the next prospective attempt;
- * the second parameter is the most recent exception. The policy returns a
- * Future<bool> which, when completed with true, indicates that a retry is
- * desired.
- *
- * We provide a few generic policies:
- * - Basic
- * - CappedJitteredexponentialBackoff
- *
- * Custom policies may use the most recent try number and exception to decide
- * whether to retry and optionally to do something interesting like delay
- * before the retry. Users may pass inline lambda expressions as policies, or
- * may define their own data types meeting the above requirements. Users are
- * responsible for managing the lifetimes of anything pointed to or referred to
- * from inside the policy.
- *
- * For example, one custom policy may try up to k times, but only if the most
- * recent exception is one of a few types or has one of a few error codes
- * indicating that the failure was transitory.
- *
- * Cancellation is not supported.
- *
- * If both FF and Policy inline executes, then it is possible to hit a stack
- * overflow due to the recursive nature of the retry implementation
- */
-template <class Policy, class FF>
-typename std::result_of<FF(size_t)>::type
-retrying(Policy&& p, FF&& ff);
-
-/**
- * generic retrying policies
- */
-
-inline
-std::function<bool(size_t, const exception_wrapper&)>
-retryingPolicyBasic(
- size_t max_tries);
-
-template <class Policy, class URNG>
-std::function<Future<bool>(size_t, const exception_wrapper&)>
-retryingPolicyCappedJitteredExponentialBackoff(
- size_t max_tries,
- Duration backoff_min,
- Duration backoff_max,
- double jitter_param,
- URNG&& rng,
- Policy&& p);
-
-inline
-std::function<Future<bool>(size_t, const exception_wrapper&)>
-retryingPolicyCappedJitteredExponentialBackoff(
- size_t max_tries,
- Duration backoff_min,
- Duration backoff_max,
- double jitter_param);
-
-}
-
-} // namespace
+} // namespace folly
projects / folly.git / blobdiff