[thread] using Boost.Thread with move-only arguments

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Re: [boost] GSoC 2013 :...

Fernando Pelliccioni

4 Apr 2013 4 Apr '13

2:40 a.m.

Hi Vicente, I have an issue with Boost.Thread contructor using move-only type arguments. The "Thread Constructor with arguments" section of the documentation says ... template thread(F f,A1 a1,A2 a2,...); Preconditions: F and each An must by copyable or movable. http://www.boost.org/doc/libs/1_53_0/doc/html/thread/thread_management.html#... "An" could be copyable or movable, but the following example fails to compile... error: use of deleted function 'A::A(const A&)' //Begin code ------------------------------------ #include struct A { A() = default; A( const A& other) = delete; A& operator=( const A& other) = delete; A( A&& other) = default; A& operator=( A&& other) = default; void run() {} }; void f( A a ) { a.run(); } void exec_boost() { A a; boost::thread t( f, std::move(a) ); t.join(); } //End code -------------------------------------- I think we should modify ... template thread(F f,A1 a1,typename disable_if, dummy* >::type=0): thread_info(make_thread_info(boost::bind(boost::type<void>(),f,a1))) { start_thread(); } ... by ... template thread(F&& f,A1&& a1,typename disable_if, dummy* >::type=0): thread_info(make_thread_info(boost::bind(boost::type<void>(),f,boost::forward<A1>(a1)))) { start_thread(); } ( In the all family of related ctors in "boost/thread/detail/thread.hpp" ) But, I don't know if boost::bind is forwarding its arguments I think we should modify Boost.Bind to be similar to std::bind. Is there any reason why Bind has not changed so far? Have you found any limitations? If Bind can not be changed, I think Boost.Thread should use some other tool similar to Bind to make forwarding parameters. GCC Libstdc++ use a Bind-lite tool for std::thread. I can work on this if you want. What do you think? Environment: Windows 7 64bits MinGW - GCC 4.7.2 MSVC 2010 MSVC 2012 Boost 1.53.0 Non-Variadic template code branch Regards, Fernando Pelliccioni

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Vicente J. Botet Escriba

4 Apr 4 Apr

6:19 a.m.

Le 04/04/13 04:40, Fernando Pelliccioni a écrit :

...

Hi Vicente,

I have an issue with Boost.Thread contructor using move-only type arguments.

The "Thread Constructor with arguments" section of the documentation says ...

template thread(F f,A1 a1,A2 a2,...);

Preconditions: F and each An must by copyable or movable.

http://www.boost.org/doc/libs/1_53_0/doc/html/thread/thread_management.html#...

"An" could be copyable or movable, but the following example fails to compile...

error: use of deleted function 'A::A(const A&)'

Sorry, if the documentation is not clear. I should add a link to the Move emulation section (http://www.boost.org/doc/libs/1_53_0/doc/html/thread/emulations.html#thread....) for each function having rvalue references if the documentation is not clear. Please could you create a Ticket for that? Which Boost.Thread version are you using? That is, BOOST_THREAD_VERSION is 2, 3 or 4? Could you try by defining BOOST_THREAD_USES_MOVE, BOOST_THREAD_VERSION 3 or BOOST_THREAD_VERSION 4?

...

I think we should modify ...

template thread(F f,A1 a1,typename disable_if, dummy* >::type=0): thread_info(make_thread_info(boost::bind(boost::type<void>(),f,a1))) { start_thread(); }

... by ...

template thread(F&& f,A1&& a1,typename disable_if, dummy* >::type=0):

thread_info(make_thread_info(boost::bind(boost::type<void>(),f,boost::forward<A1>(a1)))) { start_thread(); }

( In the all family of related ctors in "boost/thread/detail/thread.hpp" )

But, I don't know if boost::bind is forwarding its arguments

...

I think we should modify Boost.Bind to be similar to std::bind. Is there any reason why Bind has not changed so far? Have you found any limitations? IIRC, I requested the feature long-long time ago.

If Bind can not be changed, I think Boost.Thread should use some other tool similar to Bind to make forwarding parameters. GCC Libstdc++ use a Bind-lite tool for std::thread. I have taken in account some cases, but not everything works yet. E.g

No. The problem is that boost::bind doesn't supports move semantics (Boost.Move). the prototype that you need is template <class F> explicit thread(BOOST_THREAD_RV_REF(F) f , typename disable_if, dummy* >::type=0 ); I suspect that you need to follow the instructions given in http://www.boost.org/doc/libs/1_53_0/doc/html/thread/emulations.html#thread.... to make your class A movable :(

...

I can work on this if you want. What do you think?

I'm all for a boost::bind or boost::bind-lite supporting boost semantics (using Boost.Move). If you can work on this a propose a patch to boost bind I'm sure all the Boost community will thank you. There are a lot of basic Boost libraries that need an update to support move semantics (as Tuple, Fusion, SmartPtr, Exception?) so that other libraries can built on them. Any effort on this sens will be much appreciated. Please, let me know if you have some trouble after defining one of the following #define BOOST_THREAD_USES_MOVE #define BOOST_THREAD_VERSION 3 #define BOOST_THREAD_VERSION 4 Best, Vicente

Fernando Pelliccioni

7 Apr 7 Apr

10:15 p.m.

On Thu, Apr 4, 2013 at 3:19 AM, Vicente J. Botet Escriba < vicente.botet@wanadoo.fr> wrote:

...

Le 04/04/13 04:40, Fernando Pelliccioni a écrit :

Hi Vicente,

...
I have an issue with Boost.Thread contructor using move-only type arguments.

The "Thread Constructor with arguments" section of the documentation says ...

template thread(F f,A1 a1,A2 a2,...);

Preconditions: F and each An must by copyable or movable.

http://www.boost.org/doc/libs/**1_53_0/doc/html/thread/thread_** management.html#thread.thread_**management.thread.multiple_** argument_constructorhttp://www.boost.org/doc/libs/1_53_0/doc/html/thread/thread_management.html#...

"An" could be copyable or movable, but the following example fails to compile...

error: use of deleted function 'A::A(const A&)'

Sorry, if the documentation is not clear. I should add a link to the

Move emulation section (http://www.boost.org/doc/** libs/1_53_0/doc/html/thread/**emulations.html#thread.**emulations.movehttp://www.boost.org/doc/libs/1_53_0/doc/html/thread/emulations.html#thread....) for each function having rvalue references if the documentation is not clear. Please could you create a Ticket for that?

Which Boost.Thread version are you using? That is, BOOST_THREAD_VERSION is 2, 3 or 4? Could you try by defining BOOST_THREAD_USES_MOVE, BOOST_THREAD_VERSION 3 or BOOST_THREAD_VERSION 4?

...
I think we should modify ...

template thread(F f,A1 a1,typename disable_if
...
, dummy* >::type=0): thread_info(make_thread_info(**boost::bind(boost::type<void>(** ),f,a1))) { start_thread(); }

... by ...

template thread(F&& f,A1&& a1,typename disable_if
...
, dummy* >::type=0):

thread_info(make_thread_info(**boost::bind(boost::type<void>(** ),f,boost::forward<A1>(a1)))) { start_thread(); }

( In the all family of related ctors in "boost/thread/detail/thread.**hpp" )

But, I don't know if boost::bind is forwarding its arguments

No. The problem is that boost::bind doesn't supports move semantics (Boost.Move).

I think we should modify Boost.Bind to be similar to std::bind.

...
Is there any reason why Bind has not changed so far? Have you found any limitations?

IIRC, I requested the feature long-long time ago.

...
If Bind can not be changed, I think Boost.Thread should use some other tool similar to Bind to make forwarding parameters. GCC Libstdc++ use a Bind-lite tool for std::thread.

I have taken in account some cases, but not everything works yet. E.g the prototype that you need is

template <class F> explicit thread(BOOST_THREAD_RV_REF(F) f , typename disable_if, dummy* >::type=0 );

I suspect that you need to follow the instructions given in http://www.boost.org/doc/libs/**1_53_0/doc/html/thread/** emulations.html#thread.**emulations.move.portablehttp://www.boost.org/doc/libs/1_53_0/doc/html/thread/emulations.html#thread....to make your class A movable :(

...
What do you think?

I'm all for a boost::bind or boost::bind-lite supporting boost semantics (using Boost.Move). If you can work on this a propose a patch to boost bind I'm sure all the Boost community will thank you. There are a lot of basic Boost libraries that need an update to support move semantics (as Tuple, Fusion, SmartPtr, Exception?) so that other

I can work on this if you want. libraries can built on them. Any effort on this sens will be much appreciated.

Please, let me know if you have some trouble after defining one of the following

#define BOOST_THREAD_USES_MOVE #define BOOST_THREAD_VERSION 3 #define BOOST_THREAD_VERSION 4

Best, Vicente

______________________________**_________________ Unsubscribe & other changes: http://lists.boost.org/** mailman/listinfo.cgi/boosthttp://lists.boost.org/mailman/listinfo.cgi/boost

Hi Vicente, I had not set BOOST_THREAD_VERSION. I just realized that is set to 2 by default. Sorry, I had no idea about Boost Thread Move emulations. I tested the code using a C++11 movable-only type and a Boost.Move movable-only type. Same compilation error if I define BOOST_THREAD_USES_MOVE and BOOST_THREAD_VERSION to 3 or 4 ( using Boost Thread Move Emulation ) #define BOOST_THREAD_USES_MOVE //#define BOOST_THREAD_VERSION 3 #define BOOST_THREAD_VERSION 4 #include <iostream> #include struct A { BOOST_THREAD_MOVABLE_ONLY(A) A() {} void run() { } }; void f( A a ) { a.run(); } void exec_boost() { A a; boost::thread t( f, std::move(a) ); t.join(); } error: use of deleted function 'A::A(const A&)' I'll wok on Boost.Bind trying to make it move-enabled. Thank you for your dedication and patience. Regards, Fernando.

Vicente J. Botet Escriba

10:33 p.m.

Le 08/04/13 00:15, Fernando Pelliccioni a écrit :

...

On Thu, Apr 4, 2013 at 3:19 AM, Vicente J. Botet Escriba < vicente.botet@wanadoo.fr> wrote:

...
Le 04/04/13 04:40, Fernando Pelliccioni a écrit :

...
I have an issue with Boost.Thread contructor using move-only type arguments.

The "Thread Constructor with arguments" section of the documentation says ...

template thread(F f,A1 a1,A2 a2,...);

Preconditions: F and each An must by copyable or movable.

http://www.boost.org/doc/libs/**1_53_0/doc/html/thread/thread_** management.html#thread.thread_**management.thread.multiple_** argument_constructorhttp://www.boost.org/doc/libs/1_53_0/doc/html/thread/thread_management.html#...

"An" could be copyable or movable, but the following example fails to compile...

error: use of deleted function 'A::A(const A&)'

Sorry, if the documentation is not clear. I should add a link to the Move emulation section (http://www.boost.org/doc/**

Hi Vicente, libs/1_53_0/doc/html/thread/**emulations.html#thread.**emulations.movehttp://www.boost.org/doc/libs/1_53_0/doc/html/thread/emulations.html#thread....) for each function having rvalue references if the documentation is not clear. Please could you create a Ticket for that?

Which Boost.Thread version are you using? That is, BOOST_THREAD_VERSION is 2, 3 or 4? Could you try by defining BOOST_THREAD_USES_MOVE, BOOST_THREAD_VERSION 3 or BOOST_THREAD_VERSION 4?

...
I think we should modify ...

template thread(F f,A1 a1,typename disable_if
...
, dummy* >::type=0): thread_info(make_thread_info(**boost::bind(boost::type<void>(** ),f,a1))) { start_thread(); }

... by ...

template thread(F&& f,A1&& a1,typename disable_if
...
, dummy* >::type=0):

thread_info(make_thread_info(**boost::bind(boost::type<void>(** ),f,boost::forward<A1>(a1)))) { start_thread(); }

( In the all family of related ctors in "boost/thread/detail/thread.**hpp" )

But, I don't know if boost::bind is forwarding its arguments

No. The problem is that boost::bind doesn't supports move semantics (Boost.Move).

I think we should modify Boost.Bind to be similar to std::bind.

...
Is there any reason why Bind has not changed so far? Have you found any limitations?

IIRC, I requested the feature long-long time ago.

...
If Bind can not be changed, I think Boost.Thread should use some other tool similar to Bind to make forwarding parameters. GCC Libstdc++ use a Bind-lite tool for std::thread.

I have taken in account some cases, but not everything works yet. E.g the prototype that you need is

template <class F> explicit thread(BOOST_THREAD_RV_REF(F) f , typename disable_if, dummy* >::type=0 );

I suspect that you need to follow the instructions given in http://www.boost.org/doc/libs/**1_53_0/doc/html/thread/** emulations.html#thread.**emulations.move.portablehttp://www.boost.org/doc/libs/1_53_0/doc/html/thread/emulations.html#thread....to make your class A movable :(

...
What do you think?

I'm all for a boost::bind or boost::bind-lite supporting boost semantics (using Boost.Move). If you can work on this a propose a patch to boost bind I'm sure all the Boost community will thank you. There are a lot of basic Boost libraries that need an update to support move semantics (as Tuple, Fusion, SmartPtr, Exception?) so that other

I can work on this if you want. libraries can built on them. Any effort on this sens will be much appreciated.

Please, let me know if you have some trouble after defining one of the following

#define BOOST_THREAD_USES_MOVE #define BOOST_THREAD_VERSION 3 #define BOOST_THREAD_VERSION 4

Best, Vicente

______________________________**_________________ Unsubscribe & other changes: http://lists.boost.org/** mailman/listinfo.cgi/boosthttp://lists.boost.org/mailman/listinfo.cgi/boost

Hi Vicente,

I had not set BOOST_THREAD_VERSION. I just realized that is set to 2 by default. Sorry, I had no idea about Boost Thread Move emulations. I tested the code using a C++11 movable-only type and a Boost.Move movable-only type.

Same compilation error if I define BOOST_THREAD_USES_MOVE and BOOST_THREAD_VERSION to 3 or 4 ( using Boost Thread Move Emulation )

#define BOOST_THREAD_USES_MOVE //#define BOOST_THREAD_VERSION 3 #define BOOST_THREAD_VERSION 4

#include <iostream> #include

struct A { BOOST_THREAD_MOVABLE_ONLY(A)

A() {}

void run() { } };

void f( A a ) { a.run(); }

void exec_boost() { A a; boost::thread t( f, std::move(a) ); t.join(); }

error: use of deleted function 'A::A(const A&)'

I'll wok on Boost.Bind trying to make it move-enabled.

Thank you for your dedication and patience. You are welcome.

Could you try with class A : public noncopyable { BOOST_THREAD_MOVABLE_ONLY(A) public: A(int ) {} A(BOOST_THREAD_RV_REF(A) ) {} A& operator=(BOOST_THREAD_RV_REF(A) ) { return *this;} }; BOOST_THREAD_DCL_MOVABLE_BEG(T) A BOOST_THREAD_DCL_MOVABLE_END Vicente

Vicente J. Botet Escriba

10:36 p.m.

Le 08/04/13 00:33, Vicente J. Botet Escriba a écrit :

...

Le 08/04/13 00:15, Fernando Pelliccioni a écrit :

...
On Thu, Apr 4, 2013 at 3:19 AM, Vicente J. Botet Escriba < vicente.botet@wanadoo.fr> wrote:

...
Le 04/04/13 04:40, Fernando Pelliccioni a écrit :

...
I have an issue with Boost.Thread contructor using move-only type arguments.

The "Thread Constructor with arguments" section of the documentation says ...

template thread(F f,A1 a1,A2 a2,...);

Preconditions: F and each An must by copyable or movable.

http://www.boost.org/doc/libs/**1_53_0/doc/html/thread/thread_** management.html#thread.thread_**management.thread.multiple_** argument_constructorhttp://www.boost.org/doc/libs/1_53_0/doc/html/thread/thread_management.html#...

"An" could be copyable or movable, but the following example fails to compile...

error: use of deleted function 'A::A(const A&)'

Sorry, if the documentation is not clear. I should add a link to the Move emulation section (http://www.boost.org/doc/**

Hi Vicente, libs/1_53_0/doc/html/thread/**emulations.html#thread.**emulations.movehttp://www.boost.org/doc/libs/1_53_0/doc/html/thread/emulations.html#thread....)

for each function having rvalue references if the documentation is not clear. Please could you create a Ticket for that?

Which Boost.Thread version are you using? That is, BOOST_THREAD_VERSION is 2, 3 or 4? Could you try by defining BOOST_THREAD_USES_MOVE, BOOST_THREAD_VERSION 3 or BOOST_THREAD_VERSION 4?

...
I think we should modify ...

template thread(F f,A1 a1,typename disable_if
...
, dummy* >::type=0): thread_info(make_thread_info(**boost::bind(boost::type<void>(** ),f,a1))) { start_thread(); }

... by ...

template thread(F&& f,A1&& a1,typename disable_if
...
, dummy* >::type=0):

thread_info(make_thread_info(**boost::bind(boost::type<void>(** ),f,boost::forward<A1>(a1)))) { start_thread(); }

( In the all family of related ctors in "boost/thread/detail/thread.**hpp" )

But, I don't know if boost::bind is forwarding its arguments

No. The problem is that boost::bind doesn't supports move semantics (Boost.Move).

I think we should modify Boost.Bind to be similar to std::bind.

...
Is there any reason why Bind has not changed so far? Have you found any limitations?

IIRC, I requested the feature long-long time ago.

...
If Bind can not be changed, I think Boost.Thread should use some other tool similar to Bind to make forwarding parameters. GCC Libstdc++ use a Bind-lite tool for std::thread.

I have taken in account some cases, but not everything works yet. E.g the prototype that you need is

template <class F> explicit thread(BOOST_THREAD_RV_REF(F) f , typename disable_if, dummy* >::type=0 );

I suspect that you need to follow the instructions given in http://www.boost.org/doc/libs/**1_53_0/doc/html/thread/** emulations.html#thread.**emulations.move.portablehttp://www.boost.org/doc/libs/1_53_0/doc/html/thread/emulations.html#thread....to make your class A movable :(

...
What do you think?

I'm all for a boost::bind or boost::bind-lite supporting boost semantics (using Boost.Move). If you can work on this a propose a patch to boost bind I'm sure all the Boost community will thank you. There are a lot of basic Boost libraries that need an update to support move semantics (as Tuple, Fusion, SmartPtr, Exception?) so that other

I can work on this if you want. libraries can built on them. Any effort on this sens will be much appreciated.

Please, let me know if you have some trouble after defining one of the following

#define BOOST_THREAD_USES_MOVE #define BOOST_THREAD_VERSION 3 #define BOOST_THREAD_VERSION 4

Best, Vicente

______________________________**_________________ Unsubscribe & other changes: http://lists.boost.org/** mailman/listinfo.cgi/boosthttp://lists.boost.org/mailman/listinfo.cgi/boost

Hi Vicente,

I had not set BOOST_THREAD_VERSION. I just realized that is set to 2 by default. Sorry, I had no idea about Boost Thread Move emulations. I tested the code using a C++11 movable-only type and a Boost.Move movable-only type.

Same compilation error if I define BOOST_THREAD_USES_MOVE and BOOST_THREAD_VERSION to 3 or 4 ( using Boost Thread Move Emulation )

#define BOOST_THREAD_USES_MOVE //#define BOOST_THREAD_VERSION 3 #define BOOST_THREAD_VERSION 4

#include <iostream> #include

struct A { BOOST_THREAD_MOVABLE_ONLY(A)

A() {}

void run() { } };

void f( A a ) { a.run(); }

void exec_boost() { A a; boost::thread t( f, std::move(a) ); t.join(); }

error: use of deleted function 'A::A(const A&)'

I'll wok on Boost.Bind trying to make it move-enabled.

Thank you for your dedication and patience. You are welcome.

Could you try with

class A : public noncopyable { BOOST_THREAD_MOVABLE_ONLY(A)

public: A(int ) {}

A(BOOST_THREAD_RV_REF(A) ) {}

A& operator=(BOOST_THREAD_RV_REF(A) ) { return *this;}

};

BOOST_THREAD_DCL_MOVABLE_BEG(T) A BOOST_THREAD_DCL_MOVABLE_END

Sorry I meant BOOST_THREAD_DCL_MOVABLE(A) Vicente

Fernando Pelliccioni

10:59 p.m.

On Sun, Apr 7, 2013 at 7:36 PM, Vicente J. Botet Escriba < vicente.botet@wanadoo.fr> wrote:

...

Le 08/04/13 00:33, Vicente J. Botet Escriba a écrit :

Le 08/04/13 00:15, Fernando Pelliccioni a écrit :

...
...
On Thu, Apr 4, 2013 at 3:19 AM, Vicente J. Botet Escriba < vicente.botet@wanadoo.fr> wrote:

Le 04/04/13 04:40, Fernando Pelliccioni a écrit :

...
Hi Vicente,

...
I have an issue with Boost.Thread contructor using move-only type arguments.

The "Thread Constructor with arguments" section of the documentation says ...

template thread(F f,A1 a1,A2 a2,...);

Preconditions: F and each An must by copyable or movable.

http://www.boost.org/doc/libs/****1_53_0/doc/html/thread/**thread_**http://www.boost.org/doc/libs/**1_53_0/doc/html/thread/thread_** management.html#thread.thread_****management.thread.multiple_**** argument_constructor<http://**www.boost.org/doc/libs/1_53_0/** doc/html/thread/thread_**management.html#thread.thread_** management.thread.multiple_**argument_constructorhttp://www.boost.org/doc/libs/1_53_0/doc/html/thread/thread_management.html#...>

"An" could be copyable or movable, but the following example fails to compile...

error: use of deleted function 'A::A(const A&)'

Sorry, if the documentation is not clear. I should add a link to the

Move emulation section (http://www.boost.org/doc/** libs/1_53_0/doc/html/thread/****emulations.html#thread.**** emulations.move<http://www.**boost.org/doc/libs/1_53_0/doc/** html/thread/emulations.html#**thread.emulations.movehttp://www.boost.org/doc/libs/1_53_0/doc/html/thread/emulations.html#thread....>)

for each function having rvalue references if the documentation is not clear. Please could you create a Ticket for that?

Which Boost.Thread version are you using? That is, BOOST_THREAD_VERSION is 2, 3 or 4? Could you try by defining BOOST_THREAD_USES_MOVE, BOOST_THREAD_VERSION 3 or BOOST_THREAD_VERSION 4?

...
I think we should modify ...

template thread(F f,A1 a1,typename disable_if
...
,

dummy* >::type=0): thread_info(make_thread_info(****boost::bind(boost::type<void>**(** ),f,a1))) { start_thread(); }

... by ...

template thread(F&& f,A1&& a1,typename disable_if
...
,

dummy* >::type=0):

thread_info(make_thread_info(****boost::bind(boost::type<void>**(** ),f,boost::forward<A1>(a1)))) { start_thread(); }

( In the all family of related ctors in "boost/thread/detail/thread.** **hpp" )

But, I don't know if boost::bind is forwarding its arguments

No. The problem is that boost::bind doesn't supports move semantics (Boost.Move).

I think we should modify Boost.Bind to be similar to std::bind.

...
Is there any reason why Bind has not changed so far? Have you found any limitations?

IIRC, I requested the feature long-long time ago.

...
tool similar to Bind to make forwarding parameters. GCC Libstdc++ use a Bind-lite tool for std::thread.

I have taken in account some cases, but not everything works yet. E.g

If Bind can not be changed, I think Boost.Thread should use some other the prototype that you need is

template <class F> explicit thread(BOOST_THREAD_RV_REF(F) f , typename disable_if, dummy* >::type=0 );

I suspect that you need to follow the instructions given in http://www.boost.org/doc/libs/****1_53_0/doc/html/thread/**http://www.boost.org/doc/libs/**1_53_0/doc/html/thread/** emulations.html#thread.****emulations.move.portablehttp://www.boost.org/doc/libs/1_53_0/doc/html/thread/emulations.html#thread....>to make your class A movable :(

I can work on this if you want.

...
What do you think?

I'm all for a boost::bind or boost::bind-lite supporting boost semantics

(using Boost.Move). If you can work on this a propose a patch to boost bind I'm sure all the Boost community will thank you. There are a lot of basic Boost libraries that need an update to support move semantics (as Tuple, Fusion, SmartPtr, Exception?) so that other libraries can built on them. Any effort on this sens will be much appreciated.

Please, let me know if you have some trouble after defining one of the following

#define BOOST_THREAD_USES_MOVE #define BOOST_THREAD_VERSION 3 #define BOOST_THREAD_VERSION 4

Best, Vicente

______________________________****_________________ Unsubscribe & other changes: http://lists.boost.org/** mailman/listinfo.cgi/boosthttp://lists.boost.org/mailman/listinfo.cgi/boost>

Hi Vicente,

I had not set BOOST_THREAD_VERSION. I just realized that is set to 2 by default. Sorry, I had no idea about Boost Thread Move emulations. I tested the code using a C++11 movable-only type and a Boost.Move movable-only type.

Same compilation error if I define BOOST_THREAD_USES_MOVE and BOOST_THREAD_VERSION to 3 or 4 ( using Boost Thread Move Emulation )

#define BOOST_THREAD_USES_MOVE //#define BOOST_THREAD_VERSION 3 #define BOOST_THREAD_VERSION 4

#include <iostream> #include

struct A { BOOST_THREAD_MOVABLE_ONLY(A)

A() {}

void run() { } };

void f( A a ) { a.run(); }

void exec_boost() { A a; boost::thread t( f, std::move(a) ); t.join(); }

error: use of deleted function 'A::A(const A&)'

I'll wok on Boost.Bind trying to make it move-enabled.

Thank you for your dedication and patience.

You are welcome.

Could you try with

class A : public noncopyable { BOOST_THREAD_MOVABLE_ONLY(A)

public: A(int ) {}

A(BOOST_THREAD_RV_REF(A) ) {}

A& operator=(BOOST_THREAD_RV_REF(**A) ) { return *this;}

};

BOOST_THREAD_DCL_MOVABLE_BEG(**T) A BOOST_THREAD_DCL_MOVABLE_END

Sorry I meant

BOOST_THREAD_DCL_MOVABLE(A)

Vicente

______________________________**_________________ Unsubscribe & other changes: http://lists.boost.org/** mailman/listinfo.cgi/boosthttp://lists.boost.org/mailman/listinfo.cgi/boost

Hi Vicente, Same error... //Begin code ------------------------------------------------------ #define BOOST_THREAD_USES_MOVE //#define BOOST_THREAD_VERSION 3 #define BOOST_THREAD_VERSION 4 #include class A : public boost::noncopyable { BOOST_THREAD_MOVABLE_ONLY(A) public: A( int ) {} A(BOOST_THREAD_RV_REF(A) ) {} A& operator=(BOOST_THREAD_RV_REF(A) ) { return *this; } void run() { } }; //BOOST_THREAD_DCL_MOVABLE_BEG(T) A BOOST_THREAD_DCL_MOVABLE_END BOOST_THREAD_DCL_MOVABLE(A) void f( A a ) { a.run(); } void exec_boost() { A a(1); boost::thread t( f, std::move(a) ); //t.join(); } //End code ------------------------------------------------------ The error occurs in boost/thread/detail/thread.hpp line 389 Trunk revision 83652 template thread(F f,A1 a1,typename disable_if, dummy* >::type=0): line 389: thread_info(make_thread_info(boost::bind(boost::type<void>(),f,a1))) { start_thread(); } parameter a1 is not a BOOST_THREAD_RV_REF(A1) and is not moved. I think it should be: template thread(F f, BOOST_THREAD_RV_REF(A1) a1,typename disable_if, dummy* >::type=0): line 389: thread_info(make_thread_info(boost::bind(boost::type<void>(),f, boost::move(a1) ))) { start_thread(); } But in this case the error will occur within Boost.Bind Thanks and regards, Fernando.

Vicente J. Botet Escriba

11:16 p.m.

Le 08/04/13 00:59, Fernando Pelliccioni a écrit :

...

On Sun, Apr 7, 2013 at 7:36 PM, Vicente J. Botet Escriba < vicente.botet@wanadoo.fr> wrote:

...
Le 08/04/13 00:33, Vicente J. Botet Escriba a écrit :

Le 08/04/13 00:15, Fernando Pelliccioni a écrit :

...
...
On Thu, Apr 4, 2013 at 3:19 AM, Vicente J. Botet Escriba < vicente.botet@wanadoo.fr> wrote:

Le 04/04/13 04:40, Fernando Pelliccioni a écrit :

...
Hi Vicente,

...
I have an issue with Boost.Thread contructor using move-only type arguments.

The "Thread Constructor with arguments" section of the documentation says ...

template thread(F f,A1 a1,A2 a2,...);

Preconditions: F and each An must by copyable or movable.

http://www.boost.org/doc/libs/****1_53_0/doc/html/thread/**thread_**http://www.boost.org/doc/libs/**1_53_0/doc/html/thread/thread_** management.html#thread.thread_****management.thread.multiple_**** argument_constructor<http://**www.boost.org/doc/libs/1_53_0/** doc/html/thread/thread_**management.html#thread.thread_** management.thread.multiple_**argument_constructorhttp://www.boost.org/doc/libs/1_53_0/doc/html/thread/thread_management.html#...>

"An" could be copyable or movable, but the following example fails to compile...

error: use of deleted function 'A::A(const A&)'

Sorry, if the documentation is not clear. I should add a link to the

Move emulation section (http://www.boost.org/doc/** libs/1_53_0/doc/html/thread/****emulations.html#thread.**** emulations.move<http://www.**boost.org/doc/libs/1_53_0/doc/** html/thread/emulations.html#**thread.emulations.movehttp://www.boost.org/doc/libs/1_53_0/doc/html/thread/emulations.html#thread....>)

for each function having rvalue references if the documentation is not clear. Please could you create a Ticket for that?

Which Boost.Thread version are you using? That is, BOOST_THREAD_VERSION is 2, 3 or 4? Could you try by defining BOOST_THREAD_USES_MOVE, BOOST_THREAD_VERSION 3 or BOOST_THREAD_VERSION 4?

...
I think we should modify ...

template thread(F f,A1 a1,typename disable_if
> , > dummy* >::type=0): thread_info(make_thread_info(****boost::bind(boost::type<void>**(** ),f,a1))) { start_thread(); }

... by ...

template thread(F&& f,A1&& a1,typename disable_if
> , > dummy* >::type=0):

thread_info(make_thread_info(****boost::bind(boost::type<void>**(** ),f,boost::forward<A1>(a1)))) { start_thread(); }

( In the all family of related ctors in "boost/thread/detail/thread.** **hpp" )

But, I don't know if boost::bind is forwarding its arguments

No. The problem is that boost::bind doesn't supports move semantics (Boost.Move).

I think we should modify Boost.Bind to be similar to std::bind.

...
Is there any reason why Bind has not changed so far? Have you found any limitations?

IIRC, I requested the feature long-long time ago.

...
tool similar to Bind to make forwarding parameters. GCC Libstdc++ use a Bind-lite tool for std::thread.

I have taken in account some cases, but not everything works yet. E.g

If Bind can not be changed, I think Boost.Thread should use some other the prototype that you need is

template <class F> explicit thread(BOOST_THREAD_RV_REF(F) f , typename disable_if, dummy* >::type=0 );

I suspect that you need to follow the instructions given in http://www.boost.org/doc/libs/****1_53_0/doc/html/thread/**http://www.boost.org/doc/libs/**1_53_0/doc/html/thread/** emulations.html#thread.****emulations.move.portablehttp://www.boost.org/doc/libs/1_53_0/doc/html/thread/emulations.html#thread....>to make your class A movable :(

I can work on this if you want.

...
What do you think?

I'm all for a boost::bind or boost::bind-lite supporting boost semantics

(using Boost.Move). If you can work on this a propose a patch to boost bind I'm sure all the Boost community will thank you. There are a lot of basic Boost libraries that need an update to support move semantics (as Tuple, Fusion, SmartPtr, Exception?) so that other libraries can built on them. Any effort on this sens will be much appreciated.

Please, let me know if you have some trouble after defining one of the following

#define BOOST_THREAD_USES_MOVE #define BOOST_THREAD_VERSION 3 #define BOOST_THREAD_VERSION 4

Best, Vicente

______________________________****_________________ Unsubscribe & other changes: http://lists.boost.org/** mailman/listinfo.cgi/boosthttp://lists.boost.org/mailman/listinfo.cgi/boost>

Hi Vicente,

I had not set BOOST_THREAD_VERSION. I just realized that is set to 2 by default. Sorry, I had no idea about Boost Thread Move emulations. I tested the code using a C++11 movable-only type and a Boost.Move movable-only type.

Same compilation error if I define BOOST_THREAD_USES_MOVE and BOOST_THREAD_VERSION to 3 or 4 ( using Boost Thread Move Emulation )

#define BOOST_THREAD_USES_MOVE //#define BOOST_THREAD_VERSION 3 #define BOOST_THREAD_VERSION 4

#include <iostream> #include

struct A { BOOST_THREAD_MOVABLE_ONLY(A)

A() {}

void run() { } };

void f( A a ) { a.run(); }

void exec_boost() { A a; boost::thread t( f, std::move(a) ); t.join(); }

error: use of deleted function 'A::A(const A&)'

I'll wok on Boost.Bind trying to make it move-enabled.

Thank you for your dedication and patience.

You are welcome.

Could you try with

class A : public noncopyable { BOOST_THREAD_MOVABLE_ONLY(A)

public: A(int ) {}

A(BOOST_THREAD_RV_REF(A) ) {}

A& operator=(BOOST_THREAD_RV_REF(**A) ) { return *this;}

};

BOOST_THREAD_DCL_MOVABLE_BEG(**T) A BOOST_THREAD_DCL_MOVABLE_END

Sorry I meant

BOOST_THREAD_DCL_MOVABLE(A)

Vicente

______________________________**_________________ Unsubscribe & other changes: http://lists.boost.org/** mailman/listinfo.cgi/boosthttp://lists.boost.org/mailman/listinfo.cgi/boost

Hi Vicente,

Same error...

//Begin code ------------------------------------------------------ #define BOOST_THREAD_USES_MOVE //#define BOOST_THREAD_VERSION 3 #define BOOST_THREAD_VERSION 4

#include

class A : public boost::noncopyable { BOOST_THREAD_MOVABLE_ONLY(A)

public: A( int ) {}

A(BOOST_THREAD_RV_REF(A) ) {} A& operator=(BOOST_THREAD_RV_REF(A) ) { return *this; }

void run() { } };

//BOOST_THREAD_DCL_MOVABLE_BEG(T) A BOOST_THREAD_DCL_MOVABLE_END BOOST_THREAD_DCL_MOVABLE(A)

void f( A a ) { a.run(); }

void exec_boost() { A a(1); boost::thread t( f, std::move(a) ); //t.join(); }

//End code ------------------------------------------------------

The error occurs in boost/thread/detail/thread.hpp line 389 Trunk revision 83652

template thread(F f,A1 a1,typename disable_if, dummy* >::type=0): line 389: thread_info(make_thread_info(boost::bind(boost::type<void>(),f,a1))) { start_thread(); }

parameter a1 is not a BOOST_THREAD_RV_REF(A1) and is not moved.

I think it should be:

template thread(F f, BOOST_THREAD_RV_REF(A1) a1,typename disable_if, dummy* >::type=0): line 389: thread_info(make_thread_info(boost::bind(boost::type<void>(),f, boost::move(a1) ))) { start_thread(); }

But in this case the error will occur within Boost.Bind

With which compiler? Vicente

Fernando Pelliccioni

11:37 p.m.

El abr 7, 2013 8:17 PM, "Vicente J. Botet Escriba" escribió:

...

Le 08/04/13 00:59, Fernando Pelliccioni a écrit :

...
On Sun, Apr 7, 2013 at 7:36 PM, Vicente J. Botet Escriba < vicente.botet@wanadoo.fr> wrote:

...
Le 08/04/13 00:33, Vicente J. Botet Escriba a écrit :

Le 08/04/13 00:15, Fernando Pelliccioni a écrit :

...
...
On Thu, Apr 4, 2013 at 3:19 AM, Vicente J. Botet Escriba < vicente.botet@wanadoo.fr> wrote:

Le 04/04/13 04:40, Fernando Pelliccioni a écrit :

...
Hi Vicente,

> I have an issue with Boost.Thread contructor using move-only type > arguments. > > The "Thread Constructor with arguments" section of the documentation > says > ... > > template > thread(F f,A1 a1,A2 a2,...); > > Preconditions: > F and each An must by copyable or movable. > > http://www.boost.org/doc/libs/****1_53_0/doc/html/thread/**thread_**

...

...
...
...
...
...
> management.html#thread.thread_****management.thread.multiple_**** > argument_constructor<http://**www.boost.org/doc/libs/1_53_0/** > doc/html/thread/thread_**management.html#thread.thread_** > management.thread.multiple_**argument_constructor< http://www.boost.org/doc/libs/1_53_0/doc/html/thread/thread_management.html#...

...
...
...
...
> > > > "An" could be copyable or movable, but the following example fails to > compile... > > error: use of deleted function 'A::A(const A&)' > > Sorry, if the documentation is not clear. I should add a link to > the > Move emulation section (http://www.boost.org/doc/** libs/1_53_0/doc/html/thread/****emulations.html#thread.**** emulations.move<http://www.**boost.org/doc/libs/1_53_0/doc/** html/thread/emulations.html#**thread.emulations.move< http://www.boost.org/doc/libs/1_53_0/doc/html/thread/emulations.html#thread.... )

for each function having rvalue references if the documentation is not clear. Please could you create a Ticket for that?

Which Boost.Thread version are you using? That is, BOOST_THREAD_VERSION is 2, 3 or 4? Could you try by defining BOOST_THREAD_USES_MOVE, BOOST_THREAD_VERSION 3 or BOOST_THREAD_VERSION 4?

> I think we should modify ... > > template > thread(F f,A1 a1,typename > disable_if > >> , >> > dummy* >::type=0): > thread_info(make_thread_info(****boost::bind(boost::type<void>**(** > > ),f,a1))) > { > start_thread(); > } > > > ... by ... > > template > thread(F&& f,A1&& a1,typename > disable_if > >> , >> > dummy* >::type=0): > > thread_info(make_thread_info(****boost::bind(boost::type<void>**(** > > ),f,boost::forward<A1>(a1)))) > { > start_thread(); > } > > ( In the all family of related ctors in "boost/thread/detail/thread.** > **hpp" > ) > > But, I don't know if boost::bind is forwarding its arguments > > No. The problem is that boost::bind doesn't supports move semantics

(Boost.Move).

I think we should modify Boost.Bind to be similar to std::bind.

> Is there any reason why Bind has not changed so far? Have you found any > limitations? > > IIRC, I requested the feature long-long time ago.

If Bind can not be changed, I think Boost.Thread should use some other > > tool > similar to Bind to make forwarding parameters. > GCC Libstdc++ use a Bind-lite tool for std::thread. > > I have taken in account some cases, but not everything works yet. E.g

the prototype that you need is

template <class F> explicit thread(BOOST_THREAD_RV_REF(F) f , typename disable_if

...

...
...
...
...
...
dummy* >::type=0 );

I suspect that you need to follow the instructions given in http://www.boost.org/doc/libs/****1_53_0/doc/html/thread/**< http://www.boost.org/doc/libs/**1_53_0/doc/html/thread/**> emulations.html#thread.****emulations.move.portablehttp://www.boost.org/doc/libs/1_53_0/doc/html/thread/emulations.html#thread.... to

make your class A movable :(

I can work on this if you want.

> What do you think? > > I'm all for a boost::bind or boost::bind-lite supporting boost > semantics > (using Boost.Move). If you can work on this a propose a patch to boost bind I'm sure all the Boost community will thank you. There are a lot of basic Boost libraries that need an update to support move semantics (as Tuple, Fusion, SmartPtr, Exception?) so that other libraries can built on them. Any effort on this sens will be much appreciated.

Please, let me know if you have some trouble after defining one of

http://www.boost.org/doc/libs/**1_53_0/doc/html/thread/thread_** thread>, the

...

...
...
...
...
...
following

#define BOOST_THREAD_USES_MOVE #define BOOST_THREAD_VERSION 3 #define BOOST_THREAD_VERSION 4

Best, Vicente

______________________________****_________________

Unsubscribe & other changes: http://lists.boost.org/** mailman/listinfo.cgi/boosthttp://lists.boost.org/mailman/listinfo.cgi/boost

...
...
...
...
Hi Vicente,

I had not set BOOST_THREAD_VERSION. I just realized that is set to 2 by default. Sorry, I had no idea about Boost Thread Move emulations. I tested the code using a C++11 movable-only type and a Boost.Move movable-only type.

Same compilation error if I define BOOST_THREAD_USES_MOVE and BOOST_THREAD_VERSION to 3 or 4 ( using Boost Thread Move Emulation )

#define BOOST_THREAD_USES_MOVE //#define BOOST_THREAD_VERSION 3 #define BOOST_THREAD_VERSION 4

#include <iostream> #include

struct A { BOOST_THREAD_MOVABLE_ONLY(A)

A() {}

void run() { } };

void f( A a ) { a.run(); }

void exec_boost() { A a; boost::thread t( f, std::move(a) ); t.join(); }

error: use of deleted function 'A::A(const A&)'

I'll wok on Boost.Bind trying to make it move-enabled.

Thank you for your dedication and patience.

You are welcome.

Could you try with

class A : public noncopyable { BOOST_THREAD_MOVABLE_ONLY(A)

public: A(int ) {}

A(BOOST_THREAD_RV_REF(A) ) {}

A& operator=(BOOST_THREAD_RV_REF(**A) ) { return *this;}

};

BOOST_THREAD_DCL_MOVABLE_BEG(**T) A BOOST_THREAD_DCL_MOVABLE_END

Sorry I meant

BOOST_THREAD_DCL_MOVABLE(A)

Vicente

______________________________**_________________ Unsubscribe & other changes: http://lists.boost.org/** mailman/listinfo.cgi/boost< http://lists.boost.org/mailman/listinfo.cgi/boost>

Hi Vicente,

Same error...

//Begin code ------------------------------------------------------ #define BOOST_THREAD_USES_MOVE //#define BOOST_THREAD_VERSION 3 #define BOOST_THREAD_VERSION 4

#include

class A : public boost::noncopyable { BOOST_THREAD_MOVABLE_ONLY(A)

public: A( int ) {}

A(BOOST_THREAD_RV_REF(A) ) {} A& operator=(BOOST_THREAD_RV_REF(A) ) { return *this; }

void run() { } };

//BOOST_THREAD_DCL_MOVABLE_BEG(T) A BOOST_THREAD_DCL_MOVABLE_END BOOST_THREAD_DCL_MOVABLE(A)

void f( A a ) { a.run(); }

void exec_boost() { A a(1); boost::thread t( f, std::move(a) ); //t.join(); }

//End code ------------------------------------------------------

The error occurs in boost/thread/detail/thread.hpp line 389 Trunk revision 83652

template thread(F f,A1 a1,typename disable_if, dummy* >::type=0): line 389: thread_info(make_thread_info(boost::bind(boost::type<void>(),f,a1))) { start_thread(); }

parameter a1 is not a BOOST_THREAD_RV_REF(A1) and is not moved.

I think it should be:

template thread(F f, BOOST_THREAD_RV_REF(A1) a1,typename disable_if, dummy* >::type=0): line 389: thread_info(make_thread_info(boost::bind(boost::type<void>(),f, boost::move(a1) ))) { start_thread(); }

But in this case the error will occur within Boost.Bind

With which compiler?

MinGW - GCC 4.7.1 MinGW - GCC 4.7.2

Vicente J. Botet Escriba

8 Apr 8 Apr

6:15 a.m.

Le 08/04/13 01:37, Fernando Pelliccioni a écrit :

...

El abr 7, 2013 8:17 PM, "Vicente J. Botet Escriba" escribió:

...
Le 08/04/13 00:59, Fernando Pelliccioni a écrit :

...
The error occurs in boost/thread/detail/thread.hpp line 389 Trunk revision 83652

template thread(F f,A1 a1,typename disable_if, dummy* >::type=0): line 389: thread_info(make_thread_info(boost::bind(boost::type<void>(),f,a1))) { start_thread(); }

parameter a1 is not a BOOST_THREAD_RV_REF(A1) and is not moved.

I think it should be:

template thread(F f, BOOST_THREAD_RV_REF(A1) a1,typename disable_if, dummy* >::type=0): line 389: thread_info(make_thread_info(boost::bind(boost::type<void>(),f, boost::move(a1) ))) { start_thread(); }

But in this case the error will occur within Boost.Bind

With which compiler?

MinGW - GCC 4.7.1 MinGW - GCC 4.7.2

Yes, the current implementation works only when ! defined(BOOST_NO_SFINAE_EXPR) && \ ! defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES) && \ ! defined(BOOST_NO_CXX11_DECLTYPE) && \ ! defined(BOOST_NO_CXX11_DECLTYPE_N3276) && \ ! defined(BOOST_NO_CXX11_AUTO) && \ ! defined(BOOST_NO_CXX11_RVALUE_REFERENCES) && \ ! defined(BOOST_NO_CXX11_HDR_TUPLE) Let me know if I can help you with Boost.bind. BTW, I needs just an implementation of invoke (see boost/thread/detail/invoke.hpp) and result_of. Sorry for over-quoting lastly. Vicente

Fernando Pelliccioni

10 Apr 10 Apr

12:48 a.m.

On Mon, Apr 8, 2013 at 3:15 AM, Vicente J. Botet Escriba < vicente.botet@wanadoo.fr> wrote:

...

Le 08/04/13 01:37, Fernando Pelliccioni a écrit :

...
El abr 7, 2013 8:17 PM, "Vicente J. Botet Escriba" < vicente.botet@wanadoo.fr> escribió:

...
Le 08/04/13 00:59, Fernando Pelliccioni a écrit :

...
The error occurs in boost/thread/detail/thread.hpp line 389 Trunk revision 83652

...
, dummy* >::type=0): line 389:

template thread(F f,A1 a1,typename disable_if
parameter a1 is not a BOOST_THREAD_RV_REF(A1) and is not moved.

I think it should be:

...
, dummy* >::type=0): line 389:

template thread(F f, BOOST_THREAD_RV_REF(A1) a1,typename disable_if
But in this case the error will occur within Boost.Bind

With which compiler?

MinGW - GCC 4.7.1 MinGW - GCC 4.7.2

Yes, the current implementation works only when

! defined(BOOST_NO_SFINAE_EXPR) && \ ! defined(BOOST_NO_CXX11_**VARIADIC_TEMPLATES) && \ ! defined(BOOST_NO_CXX11_**DECLTYPE) && \ ! defined(BOOST_NO_CXX11_**DECLTYPE_N3276) && \ ! defined(BOOST_NO_CXX11_AUTO) && \ ! defined(BOOST_NO_CXX11_RVALUE_**REFERENCES) && \ ! defined(BOOST_NO_CXX11_HDR_**TUPLE)

The only unsupported feature of the list is DECLTYPE_N3276 for GCC >= 4.7 http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2011/n3276.pdf ! defined(BOOST_NO_CXX11_**DECLTYPE_N3276) is not fulfilled Are we sure that GCC 4.7 does not fulfill it? Is Boost.Config right? I could not read N3276. Is it absolutely necessary to this requirement to the compiler?

...

Let me know if I can help you with Boost.bind. BTW, I needs just an implementation of invoke (see boost/thread/detail/invoke.**hpp) and result_of.

Sorry for over-quoting lastly. Vicente

Regards, Fernando.

Vicente J. Botet Escriba

5:46 a.m.

Le 10/04/13 02:48, Fernando Pelliccioni a écrit :

...

On Mon, Apr 8, 2013 at 3:15 AM, Vicente J. Botet Escriba < vicente.botet@wanadoo.fr> wrote:

...
Le 08/04/13 01:37, Fernando Pelliccioni a écrit :

...
El abr 7, 2013 8:17 PM, "Vicente J. Botet Escriba" < vicente.botet@wanadoo.fr> escribió:

Yes, the current implementation works only when

! defined(BOOST_NO_SFINAE_EXPR) && \ ! defined(BOOST_NO_CXX11_**VARIADIC_TEMPLATES) && \ ! defined(BOOST_NO_CXX11_**DECLTYPE) && \ ! defined(BOOST_NO_CXX11_**DECLTYPE_N3276) && \ ! defined(BOOST_NO_CXX11_AUTO) && \ ! defined(BOOST_NO_CXX11_RVALUE_**REFERENCES) && \ ! defined(BOOST_NO_CXX11_HDR_**TUPLE)

The only unsupported feature of the list is DECLTYPE_N3276 for GCC >= 4.7

http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2011/n3276.pdf

! defined(BOOST_NO_CXX11_**DECLTYPE_N3276) is not fulfilled

Are we sure that GCC 4.7 does not fulfill it? Is Boost.Config right?

I could not read N3276. Is it absolutely necessary to this requirement to the compiler?

It is announce for gcc-4.8.1. See the boost/thread/detail/invoke.hpp file. I have not tried to implement it using result_of, but I think that we have the same issue with the current result_of. Whether this is possible in c++03 is an open point. Best, Vicente

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