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Boost-Commit : |
Subject: [Boost-commit] svn:boost r84771 - trunk/libs/thread/doc
From: vicente.botet_at_[hidden]
Date: 2013-06-14 01:50:29
Author: viboes
Date: 2013-06-14 01:50:29 EDT (Fri, 14 Jun 2013)
New Revision: 84771
URL: http://svn.boost.org/trac/boost/changeset/84771
Log:
Thread: update history, compliance and fix some parts in external locking doc.
Text files modified:
trunk/libs/thread/doc/changes.qbk | 23 +++++++++++++++------
trunk/libs/thread/doc/compliance.qbk | 41 ++++++++++++++++++++++-----------------
trunk/libs/thread/doc/external_locking.qbk | 38 ++++++++++++++++++++++--------------
trunk/libs/thread/doc/mutex_concepts.qbk | 20 +++++++++---------
trunk/libs/thread/doc/shared_mutex_ref.qbk | 18 ++++++++--------
5 files changed, 81 insertions(+), 59 deletions(-)
Modified: trunk/libs/thread/doc/changes.qbk
==============================================================================
--- trunk/libs/thread/doc/changes.qbk Fri Jun 14 01:46:11 2013 (r84770)
+++ trunk/libs/thread/doc/changes.qbk 2013-06-14 01:50:29 EDT (Fri, 14 Jun 2013) (r84771)
@@ -13,11 +13,14 @@
[*New Features:]
-* [@http://svn.boost.org/trac/boost/ticket/8273 #8273] Add externally locked streams
-* [@http://svn.boost.org/trac/boost/ticket/8274 #8274] Add concurrent queue
-* [@http://svn.boost.org/trac/boost/ticket/8515 #8515] Async: Add shared_future::then
-* [@http://svn.boost.org/trac/boost/ticket/8518 #8518] Sync: Add a latch class
-* [@http://svn.boost.org/trac/boost/ticket/8615 #8615] Async: Replace make_future/make_shared_future by make_ready_future
+* [@http://svn.boost.org/trac/boost/ticket/8273 #8273] Synchro:Add externally locked streams.
+* [@http://svn.boost.org/trac/boost/ticket/8274 #8274] Synchro:Add concurrent queue.
+* [@http://svn.boost.org/trac/boost/ticket/8515 #8515] Async: Add shared_future::then.
+* [@http://svn.boost.org/trac/boost/ticket/8518 #8518] Synchro: Add a latch class.
+* [@http://svn.boost.org/trac/boost/ticket/8615 #8615] Async: Replace make_future/make_shared_future by make_ready_future.
+* [@http://svn.boost.org/trac/boost/ticket/8627 #8627] Async: Add future<>::unwrap.
+* [@http://svn.boost.org/trac/boost/ticket/8677 #8677] Async: Add future<>::get_or.
+* [@http://svn.boost.org/trac/boost/ticket/8678 #8678] Async: Add future<>::fallback_to.
[*Fixed Bugs:]
@@ -52,8 +55,10 @@
* [@http://svn.boost.org/trac/boost/ticket/8323 #8323] boost::thread::try_join_for/try_join_until may block indefinitely due to a combination of problems in Boost.Thread and Boost.Chrono
* [@http://svn.boost.org/trac/boost/ticket/8337 #8337] The internal representation of "std::string(this->code()->message())" escapes, but is destroyed when it exits scope.
* [@http://svn.boost.org/trac/boost/ticket/8371 #8371] C++11 once_flag enabled when constexpr is not available
+* [@http://svn.boost.org/trac/boost/ticket/8422 #8422] Assertion in win32::WaitForSingleObject()
* [@http://svn.boost.org/trac/boost/ticket/8443 #8443] Header file inclusion order may cause crashes
* [@http://svn.boost.org/trac/boost/ticket/8451 #8451] Missing documented function 'boost::scoped_thread::joinable'
+* [@http://svn.boost.org/trac/boost/ticket/8458 #8458] -DBOOST_THREAD_DONT_USE_CHRONO in thread.obj.rsp but not explicitly set
* [@http://svn.boost.org/trac/boost/ticket/8530 #8530] [Coverity] Unused variable thread_handle, uninitialized variable cond_mutex in thread/pthread/thread_data.hpp
* [@http://svn.boost.org/trac/boost/ticket/8550 #8550] static linking of Boost.Thread with an MFC-Dll
* [@http://svn.boost.org/trac/boost/ticket/8576 #8576] "sur parolle" should be "sur parole".
@@ -62,6 +67,7 @@
* [@http://svn.boost.org/trac/boost/ticket/8645 #8645] Typo in Strict lock definition
* [@http://svn.boost.org/trac/boost/ticket/8671 #8671] promise: set_..._at_thread_exit
* [@http://svn.boost.org/trac/boost/ticket/8672 #8672] future<>::then(void()) doesn't works
+* [@http://svn.boost.org/trac/boost/ticket/8674 #8674] Futures as local named objects can't be returned with implicit move.
[heading Version 4.0.0 - boost 1.53]
@@ -422,12 +428,15 @@
* [@http://svn.boost.org/trac/boost/ticket/7446 #7446] Async: Add when_any.
* [@http://svn.boost.org/trac/boost/ticket/7447 #7447] Async: Add when_all.
* [@http://svn.boost.org/trac/boost/ticket/7448 #7448] Async: Add async taking a scheduler parameter.
- * [@http://svn.boost.org/trac/boost/ticket/8515 #8515] Async: Add shared_future::then
+ * [@http://svn.boost.org/trac/boost/ticket/8515 #8515] Async: Add shared_future::then.
* [@http://svn.boost.org/trac/boost/ticket/8516 #8516] Async: Add future/shared_future::then taking a scheduler as parameter.
- * [@http://svn.boost.org/trac/boost/ticket/8517 #8517] Async: Add a variadic shared_future::then
* [@http://svn.boost.org/trac/boost/ticket/8627 #8627] Async: Add future<>::unwrap.
+# And some additional extensions related to futures as:
+ * [@http://svn.boost.org/trac/boost/ticket/8677 #8677] Async: Add future<>::get_or.
+ * [@http://svn.boost.org/trac/boost/ticket/8678 #8678] Async: Add future<>::fallback_to.
+ * [@http://svn.boost.org/trac/boost/ticket/8517 #8517] Async: Add a variadic shared_future::then.
[endsect]
Modified: trunk/libs/thread/doc/compliance.qbk
==============================================================================
--- trunk/libs/thread/doc/compliance.qbk Fri Jun 14 01:46:11 2013 (r84770)
+++ trunk/libs/thread/doc/compliance.qbk 2013-06-14 01:50:29 EDT (Fri, 14 Jun 2013) (r84771)
@@ -53,7 +53,7 @@
[[30.4.2.2.1] [unique_lock constructors, destructor, and assignment] [Yes] [-] [-]]
[[30.4.2.2.2] [unique_lock locking] [Yes] [-] [-]]
[[30.4.2.2.3] [unique_lock modifiers] [Yes] [-] [-]]
- [[30.4.2.2.4] [unique_lock observers] [Yes] [] [-]]
+ [[30.4.2.2.4] [unique_lock observers] [Yes] [ - ] [-]]
[[30.4.3] [Generic locking algorithms] [Partial] [variadic] [#6227]]
[[30.4.4] [Call once] [Yes] [-] [-]]
[[30.4.4.1] [Struct once_flag] [Yes] [-] [-]]
@@ -107,6 +107,7 @@
[section:latch C++ Latches and Barriers]
[note [@http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2013/n3600.html N3659 C++ Latches and Barriers]]
+[note [@http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2013/n3666.html N3659 C++ Latches and Barriers]]
[table C++ Latches and Barriers Conformance
[[Section] [Description] [Status] [Comments]]
@@ -125,10 +126,10 @@
[[X.1.1] [Basic Operations] [Partial] [ - ]]
[[X.1.1.1] [push] [yes] [ - ]]
[[X.1.1.2] [value_pop] [no] [ renamed pull with two flavors + a ptr_pull that returns a sharted_ptr<>. ]]
- [[X.1.2] [Non-waiting operations] [] [ - ]]
+ [[X.1.2] [Non-waiting operations] [ - ] [ - ]]
[[X.1.2.1] [try_push] [Partial] [ return bool instead ]]
[[X.1.2.2] [try_pop] [Partial] [ renamed try_pull, returns null ]]
- [[X.1.3] [Non-blocking operations] [] [ - ]]
+ [[X.1.3] [Non-blocking operations] [ - ] [ - ]]
[[X.1.3.1] [nonblocking_push] [Partial] [ renamed try_push(no_block, ]]
[[X.1.3.2] [nonblocking_pop] [Partial] [ renamed try_pop(no_block, ]]
[[X.1.4] [Push-front operations] [No] [ - ]]
@@ -148,15 +149,15 @@
[[X.1.9] [Exception Handling] [Yes?] [ - ]]
[[X.1.10] [Queue Ordering] [Yes?] [ - ]]
[[X.1.11] [Lock-Free Implementations] [No] [ waiting to stabilize the lock-based interface. Will use Boost.LockFree once it is Move aware. ]]
- [[X.2] [Concrete queues] [Partial] [ ]]
+ [[X.2] [Concrete queues] [Partial] [ - ]]
[[X.2.1] [Locking Buffer Queue] [Partial] [ classes sync_queue and a sync_bounded_queue. ]]
- [[X.2.1] [Lock-Free Buffer Queue] [No] [ ]]
- [[X.3] [Additional Conceptual Tools] [No] [ ]]
- [[X.3.1] [Fronts and Backs] [No] [ ]]
- [[X.3.2] [Streaming Iterators] [No] [ ]]
- [[X.3.3] [Storage Iterators] [No] [ ]]
- [[X.3.4] [Binary Interfaces] [No] [ ]]
- [[X.3.4] [Managed Indirection] [No] [ ]]
+ [[X.2.1] [Lock-Free Buffer Queue] [No] [ - ]]
+ [[X.3] [Additional Conceptual Tools] [No] [ - ]]
+ [[X.3.1] [Fronts and Backs] [No] [ - ]]
+ [[X.3.2] [Streaming Iterators] [No] [ - ]]
+ [[X.3.3] [Storage Iterators] [No] [ - ]]
+ [[X.3.4] [Binary Interfaces] [No] [ - ]]
+ [[X.3.4] [Managed Indirection] [No] [ - ]]
]
[endsect]
@@ -192,17 +193,18 @@
[section:async A Standardized Representation of Asynchronous Operations]
[note [@http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2013/n3558.pdf N3558 A Standardized Representation of Asynchronous Operations]]
+[note These functions are based on the [@http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2013/n3634.pdf [*N3634 - Improvements to std::future<T> and related APIs]] C++1y proposal by N. Gustafsson, A. Laksberg, H. Sutter, S. Mithani.]
-[table A Standardized Representation of Asynchronous Operations Conformance
+[table Improvements to std::future<T> and related APIs]
[[Section] [Description] [Status] [Comments]]
[[30.6.6] [Class template future] [Partial] [ - ]]
[[30.6.6.1] [then] [Partial] [ executor interface missing #8516 ]]
- [[30.6.6.2] [unwrap] [No] [ #XXXX ]]
- [[30.6.6.3] [ready] [yes] [ is_ready ]]
+ [[30.6.6.2] [unwrap] [Yes] [ - ]]
+ [[30.6.6.3] [ready] [Partial] [ is_ready ]]
[[30.6.7] [Class template shared_future] [Partial] [ - ]]
- [[30.6.7.1] [then] [No] [ #8515 ]]
+ [[30.6.7.1] [then] [Yes] [ executor interface missing #8516 ]]
[[30.6.7.2] [unwrap] [No] [ #XXXX ]]
- [[30.6.7.3] [ready] [Yes] [ is_ready ]]
+ [[30.6.7.3] [ready] [Partial] [ is_ready ]]
[[30.6.X] [Function template when_any] [No] [ #7446 ]]
[[30.6.X] [Function template when_all] [No] [ #7447 ]]
[[30.6.X] [Function template make_ready_future] [Yes] [ - ]]
@@ -211,11 +213,11 @@
[endsect]
-[section:stream_mutex C++ Stream Mutexes]
+[section:stream_mutex C++ Stream Mutexes - C++ Stream Guards]
While Boost.Thread implementation of stream mutexes differ in the approach, it is worth comparing with the current trend on the standard.
-[note [@http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2013/n3535.html N3535 - C++ Stream Mutexes]]
+[note [@http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2013/n3535.html N3535 - C++ Stream Mutexes]. This has been replaced already by N3678 - C++ Stream Guards.]
[table C++ C++ Stream MutexesConformance
[[Section] [Description] [Status] [Comments]]
@@ -234,6 +236,9 @@
[[X.4] [Predefined Objects] [No] [.]]
]
+[note [@http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2013/n3678.html N3678 - C++ Stream Guards]]
+
+
[endsect]
Modified: trunk/libs/thread/doc/external_locking.qbk
==============================================================================
--- trunk/libs/thread/doc/external_locking.qbk Fri Jun 14 01:46:11 2013 (r84770)
+++ trunk/libs/thread/doc/external_locking.qbk 2013-06-14 01:50:29 EDT (Fri, 14 Jun 2013) (r84771)
@@ -182,10 +182,12 @@
We'll call the enhanced version `strict_lock`. Essentially, a `strict_lock`'s role is only to live on the stack as an automatic variable.
`strict_lock` must adhere to a non-copy and non-alias policy.
`strict_lock` disables copying by making the copy constructor and the assignment operator private.
-While we're at it, let's disable operator new and operator delete;
+While we're at it, let's disable operator new and operator delete.
+
+[/
`strict_lock` are not intended to be allocated on the heap.
`strict_lock` avoids aliasing by using a slightly less orthodox and less well-known technique: disable address taking.
-
+]
template <typename Lockable>
class strict_lock {
@@ -229,6 +231,7 @@
// ok, Bar takes a reference to strict_lock<BankAccount>
extern void Bar(strict_lock<BankAccount>&);
+[/
* You cannot allocate a `strict_lock` on the heap. However, you still can put `strict_lock`s on the heap if they're members of a class.
strict_lock<BankAccount>* pL =
@@ -250,7 +253,7 @@
strict_lock<BankAccount>& rAlias = myLock; // ok
Fortunately, references don't engender as bad aliasing as pointers because they're much less versatile (references cannot be copied or reseated).
-
+]
[/* You can even make `strict_lock` final; that is, impossible to derive from. This task is left in the form of an exercise to the reader.
]
@@ -399,7 +402,7 @@
T& get(strict_lock<Lockable>& lock) {
- #ifndef BOOST_THREAD_EXTERNALLY_LOCKED_DONT_CHECK_SAME // define BOOST_THREAD_EXTERNALLY_LOCKED_DONT_CHECK_SAME if you don't want to check locker check the same lockable
+ #ifdef BOOST_THREAD_THROW_IF_PRECONDITION_NOT_SATISFIED
if (!lock.owns_lock(&lockable_)) throw lock_error(); run time check throw if not locks the same
#endif
return obj_;
@@ -479,7 +482,7 @@
In order to make this code compilable we need to store either a Lockable or a `unique_lock<Lockable>` reference depending on the constructor. Store which kind of reference we have stored,and in the destructor call either to the Lockable `unlock` or restore the ownership.
-This seams too complicated to me. Another possibility is to define a nested strict lock class. The drawback is that instead of having only one strict lock we have two and we need either to duplicate every function taking a `strict\_lock` or make these function templates functions. The problem with template functions is that we don't profit anymore of the C++ type system. We must add some static metafunction that check that the Locker parameter is a strict lock. The problem is that we can not really check this or can we?. The `is_strict_lock` metafunction must be specialized by the strict lock developer. We need to belive it "sur parole". The advantage is that now we can manage with more than two strict locks without changing our code. Ths is really nice.
+This seams too complicated to me. Another possibility is to define a nested strict lock class. The drawback is that instead of having only one strict lock we have two and we need either to duplicate every function taking a `strict_lock` or make these function templates functions. The problem with template functions is that we don't profit anymore of the C++ type system. We must add some static metafunction that check that the Locker parameter is a strict lock. The problem is that we can not really check this or can we?. The `is_strict_lock` metafunction must be specialized by the strict lock developer. We need to belive it "sur parole". The advantage is that now we can manage with more than two strict locks without changing our code. Ths is really nice.
Now we need to state that both classes are `strict_lock`s.
@@ -509,7 +512,7 @@
: lock_(lock) // Store reference to locker
, tmp_lock_(lock.move()) // Move ownership to temporaty locker
{
- #ifndef BOOST_THREAD_STRCIT_LOCKER_DONT_CHECK_OWNERSHIP // Define BOOST_THREAD_EXTERNALLY_LOCKED_DONT_CHECK_OWNERSHIP if you don't want to check locker ownership
+ #ifdef BOOST_THREAD_THROW_IF_PRECONDITION_NOT_SATISFIED
if (tmp_lock_.mutex()==0) {
lock_=tmp_lock_.move(); // Rollback for coherency purposes
throw lock_error();
@@ -520,24 +523,29 @@
~nested_strict_lock() {
lock_=tmp_lock_.move(); // Move ownership to nesting locker
}
- typedef bool (nested_strict_lock::*bool_type)() const;
- operator bool_type() const { return &nested_strict_lock::owns_lock; }
- bool operator!() const { return false; }
bool owns_lock() const { return true; }
lockable_type* mutex() const { return tmp_lock_.mutex(); }
bool owns_lock(lockable_type* l) const { return l==mutex(); }
- BOOST_ADRESS_OF_DELETE(nested_strict_lock)
- BOOST_HEAP_ALLOCATEION_DELETE(nested_strict_lock)
- BOOST_DEFAULT_CONSTRUCTOR_DELETE(nested_strict_lock) 8
- BOOST_COPY_CONSTRUCTOR_DELETE(nested_strict_lock) 9
- BOOST_COPY_ASSIGNEMENT_DELETE(nested_strict_lock) 10
private:
Locker& lock_;
Locker tmp_lock_;
};
+[/
+ typedef bool (nested_strict_lock::*bool_type)() const;
+ operator bool_type() const { return &nested_strict_lock::owns_lock; }
+ bool operator!() const { return false; }
+
+ BOOST_ADRESS_OF_DELETE(nested_strict_lock)
+ BOOST_HEAP_ALLOCATEION_DELETE(nested_strict_lock)
+ BOOST_DEFAULT_CONSTRUCTOR_DELETE(nested_strict_lock)
+ BOOST_COPY_CONSTRUCTOR_DELETE(nested_strict_lock)
+ BOOST_COPY_ASSIGNEMENT_DELETE(nested_strict_lock)
+
+]
+
The `externally_locked` get function is now a template function taking a Locker as parameters instead of a `strict_lock`.
We can add test in debug mode that ensure that the Lockable object is locked.
@@ -555,7 +563,7 @@
#ifndef BOOST_THREAD_EXTERNALLY_LOCKED_DONT_CHECK_OWNERSHIP // define BOOST_THREAD_EXTERNALLY_LOCKED_NO_CHECK_OWNERSHIP if you don't want to check locker ownership
if (! lock ) throw lock_error(); // run time check throw if no locked
#endif
- #ifndef BOOST_THREAD_EXTERNALLY_LOCKED_DONT_CHECK_SAME
+ #ifdef BOOST_THREAD_THROW_IF_PRECONDITION_NOT_SATISFIED
if (!lock.owns_lock(&lockable_)) throw lock_error();
#endif
return obj_;
Modified: trunk/libs/thread/doc/mutex_concepts.qbk
==============================================================================
--- trunk/libs/thread/doc/mutex_concepts.qbk Fri Jun 14 01:46:11 2013 (r84770)
+++ trunk/libs/thread/doc/mutex_concepts.qbk 2013-06-14 01:50:29 EDT (Fri, 14 Jun 2013) (r84771)
@@ -344,14 +344,14 @@
[endsect]
-[section:shared_lockable `SharedLockable` Concept -- EXTENSION]
+[section:shared_lockable `SharedLockable` Concept -- C++14]
// #include <boost/thread/lockable_concepts.hpp>
namespace boost
{
template<typename L>
- class SharedLockable; // EXTENSION
+ class SharedLockable; // C++14
}
@@ -1205,9 +1205,9 @@
template<typename Mutex>
void swap(unique_lock <Mutex>& lhs, unique_lock <Mutex>& rhs);
template<typename Lockable>
- class shared_lock; // EXTENSION
+ class shared_lock; // C++14
template<typename Mutex>
- void swap(shared_lock<Mutex>& lhs,shared_lock<Mutex>& rhs); // EXTENSION
+ void swap(shared_lock<Mutex>& lhs,shared_lock<Mutex>& rhs); // C++14
template<typename Lockable>
class upgrade_lock; // EXTENSION
template<typename Mutex>
@@ -1235,13 +1235,13 @@
unique_lock(Lockable& m_,try_to_lock_t);
#ifdef BOOST_THREAD_PROVIDES_SHARED_MUTEX_UPWARDS_CONVERSION
- unique_lock(shared_lock<mutex_type>&& sl, try_to_lock_t)
+ unique_lock(shared_lock<mutex_type>&& sl, try_to_lock_t); // C++14
template <class Clock, class Duration>
unique_lock(shared_lock<mutex_type>&& sl,
- const chrono::time_point<Clock, Duration>& abs_time);
+ const chrono::time_point<Clock, Duration>& abs_time); // C++14
template <class Rep, class Period>
unique_lock(shared_lock<mutex_type>&& sl,
- const chrono::duration<Rep, Period>& rel_time)
+ const chrono::duration<Rep, Period>& rel_time); // C++14
#endif
template <class Clock, class Duration>
@@ -1253,7 +1253,7 @@
unique_lock(unique_lock const&) = delete;
unique_lock& operator=(unique_lock const&) = delete;
unique_lock(unique_lock<Lockable>&& other) noexcept;
- explicit unique_lock(upgrade_lock<Lockable>&& other) noexcept;
+ explicit unique_lock(upgrade_lock<Lockable>&& other) noexcept; // EXTENSION
unique_lock& operator=(unique_lock<Lockable>&& other) noexcept;
@@ -1583,7 +1583,7 @@
[endsect]
-[section:shared_lock Class template `shared_lock` - EXTENSION]
+[section:shared_lock Class template `shared_lock` - C++14]
// #include <boost/thread/locks.hpp>
// #include <boost/thread/lock_types.hpp>
@@ -1621,7 +1621,7 @@
void unlock();
// Conversion from upgrade locking
- explicit shared_lock(upgrade_lock<Lockable> && other);
+ explicit shared_lock(upgrade_lock<Lockable> && other); // EXTENSION
// Conversion from exclusive locking
explicit shared_lock(unique_lock<Lockable> && other);
Modified: trunk/libs/thread/doc/shared_mutex_ref.qbk
==============================================================================
--- trunk/libs/thread/doc/shared_mutex_ref.qbk Fri Jun 14 01:46:11 2013 (r84770)
+++ trunk/libs/thread/doc/shared_mutex_ref.qbk 2013-06-14 01:50:29 EDT (Fri, 14 Jun 2013) (r84771)
@@ -5,7 +5,7 @@
http://www.boost.org/LICENSE_1_0.txt).
]
-[section:shared_mutex Class `shared_mutex` -- EXTENSION]
+[section:shared_mutex Class `shared_mutex` -- C++14]
#include <boost/thread/shared_mutex.hpp>
@@ -36,18 +36,18 @@
#if defined BOOST_THREAD_PROVIDES_DEPRECATED_FEATURES_SINCE_V3_0_0
// use upgrade_mutex instead.
- void lock_upgrade();
- void unlock_upgrade();
+ void lock_upgrade(); // EXTENSION
+ void unlock_upgrade(); // EXTENSION
- void unlock_upgrade_and_lock();
- void unlock_and_lock_upgrade();
- void unlock_and_lock_shared();
- void unlock_upgrade_and_lock_shared();
+ void unlock_upgrade_and_lock(); // EXTENSION
+ void unlock_and_lock_upgrade(); // EXTENSION
+ void unlock_and_lock_shared(); // EXTENSION
+ void unlock_upgrade_and_lock_shared(); // EXTENSION
#endif
#if defined BOOST_THREAD_USES_DATETIME
- bool timed_lock_shared(system_time const& timeout);
- bool timed_lock(system_time const& timeout);
+ bool timed_lock_shared(system_time const& timeout); // DEPRECATED
+ bool timed_lock(system_time const& timeout); // DEPRECATED
#endif
};
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