/*
- * Copyright 2014 Facebook, Inc.
+ * Copyright 2017 Facebook, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
#pragma once
-#include <folly/futures/Deprecated.h>
-#include <folly/futures/Try.h>
+#include <folly/Portability.h>
+#include <folly/Try.h>
#include <functional>
namespace folly {
// forward declaration
+template <class T>
+class SemiFuture;
template <class T> class Future;
+namespace futures {
+namespace detail {
+template <class T>
+class FutureBase;
+struct EmptyConstruct {};
+template <typename T, typename F>
+class CoreCallbackState;
+} // namespace detail
+} // namespace futures
+
template <class T>
class Promise {
-public:
+ public:
+ static Promise<T> makeEmpty() noexcept; // equivalent to moved-from
+
Promise();
~Promise();
once, thereafter Future already retrieved exception will be raised. */
Future<T> getFuture();
- /** Fulfil the Promise with an exception_wrapper */
+ /** Fulfill the Promise with an exception_wrapper */
void setException(exception_wrapper ew);
- /** Fulfil the Promise with an exception_ptr, e.g.
+ /** Fulfill the Promise with an exception_ptr, e.g.
try {
...
} catch (...) {
p.setException(std::current_exception());
}
*/
- void setException(std::exception_ptr const&) DEPRECATED;
+ FOLLY_DEPRECATED("use setException(exception_wrapper)")
+ void setException(std::exception_ptr const&);
- /** Fulfil the Promise with an exception type E, which can be passed to
+ /** Fulfill the Promise with an exception type E, which can be passed to
std::make_exception_ptr(). Useful for originating exceptions. If you
caught an exception the exception_wrapper form is more appropriate.
*/
/// Set an interrupt handler to handle interrupts. See the documentation for
/// Future::raise(). Your handler can do whatever it wants, but if you
- /// bother to set one then you probably will want to fulfil the promise with
+ /// bother to set one then you probably will want to fulfill the promise with
/// an exception (or special value) indicating how the interrupt was
/// handled.
void setInterruptHandler(std::function<void(exception_wrapper const&)>);
- /** Fulfil this Promise (only for Promise<void>) */
- void setValue();
+ /// Sugar to fulfill this Promise<Unit>
+ template <class B = T>
+ typename std::enable_if<std::is_same<Unit, B>::value, void>::type
+ setValue() {
+ setTry(Try<T>(T()));
+ }
/** Set the value (use perfect forwarding for both move and copy) */
template <class M>
void setValue(M&& value);
- void fulfilTry(Try<T> t);
+ void setTry(Try<T>&& t);
- /** Fulfil this Promise with the result of a function that takes no
+ /** Fulfill this Promise with the result of a function that takes no
arguments and returns something implicitly convertible to T.
Captures exceptions. e.g.
- p.fulfil([] { do something that may throw; return a T; });
+ p.setWith([] { do something that may throw; return a T; });
*/
template <class F>
- void fulfil(F&& func);
+ void setWith(F&& func);
+
+ bool isFulfilled() const noexcept;
-private:
+ private:
typedef typename Future<T>::corePtr corePtr;
+ template <class>
+ friend class futures::detail::FutureBase;
+ template <class>
+ friend class SemiFuture;
+ template <class>
+ friend class Future;
+ template <class, class>
+ friend class futures::detail::CoreCallbackState;
// Whether the Future has been retrieved (a one-time operation).
bool retrieved_;
// shared core state object
corePtr core_;
+ explicit Promise(futures::detail::EmptyConstruct) noexcept;
+
void throwIfFulfilled();
void throwIfRetrieved();
void detach();
};
-}
+} // namespace folly
#include <folly/futures/Future.h>
#include <folly/futures/Promise-inl.h>