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remove_pointer and pointers to members?
by John Maddock 29 Jul '08

29 Jul '08

Folks, I'm trying to decide how to fix this bug report: https://svn.boost.org/trac/boost/ticket/2011 Basically what should: remove_pointer<int (foo::*)>::type be? Should it produce an int, or have no effect? TR1 explicitly says that it has no effect, so I guess I vote to stick with that behaviour. In which case, anyone object to a remove_member_pointer trait that transforms: int (foo::*) --> int int (foo::*)(double) --> int (double) etc. It's also tempting to add a "member_object" trait at the same time that transforms: int (foo::*) --> foo int (foo::*)(double) --> foo thoughts? Thanks, John.

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Test machines available
by Ruediger Berlich 29 Jul '08

29 Jul '08

Hi there, I was wondering whether there would be a need for additional systems for automated, nightly builds. My employer would agree to make a few (3-4) machines available, with Linux-based operating systems. This would be a VMWare ESX-based setup, although on high-performance hardware (8-core blades). I would personally be most interested in a test environment with the OpenSUSE 11 64 bit / g++ 4.3.1 combo. It might be possible to also have an OpenSolaris/Intel installation there, or an installation with Intel's C++ compiler. A pre-condition would be that no external access to the machines is needed, i.e. it would not be possible for Boost members to log in. Instead, I would set up the test environment as needed, and of course it would be possible for these machines to contact the outside world and transmit test results. Thus my question, what needs to be done to set up such a test environment. Note that I cannot give a guaranty for long-term availability, as a) I do not know how much work is involved in running such an environment and b) it might become necessary for the systems to be used in other contexts. If this turns out to be pretty much self-hosting (i.e. the build-environment is self-sustained on a normally configured Linux system), I would aim to ensure that the systems are available for a longer period. Best Regards, Ruediger /*************************************************************************/ The Steinbuch Centre for Computing of Karlsruhe Institute of Technology (the Cooperation of Forschungszentrum Karlsruhe GmbH and Universitaet Karlsruhe TH) will run its annual GridKa School from September 8th to 12th, 2008. Please find further information at http://www.fzk.de/gks08 . /*************************************************************************/ Forschungszentrum Karlsruhe GmbH Sitz: Weberstraße 5 76133 Karlsruhe Amtsgericht Mannheim HRB 100302 Vorsitzende des Aufsichtsrats: Baerbel Brumme-Bothe Vors. der Geschäftsführung: Prof. Dr. Eberhard Umbach

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[1.37] When this will start?
by vicente.botet 29 Jul '08

29 Jul '08

Hi, Release 1.36 will have soon 2 weeks behind schedule. In order to maintain a quarterly release, when do you plan to start the 1.37 release? IMO it is time to start with it (1/08/2008), but without a named branch by release this is impossible. Could you share with us which is the plan to avoid that the quarterly release become a wish? Vicente

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All tools code frozen!
by Rene Rivera 29 Jul '08

29 Jul '08

Since I don't enjoy reverting changes when I don't have the time (I'm in the middle of my own product release). And since Boost is nearing the end of a release cycle. *ALL* tool changes are hereby *FROZEN* except for emergency fixes. Any changes must be approved by Beman or myself. And such changes must include making sure Boost testing runs adequately in *both* a Windows platform and a Unix platform. This means going to the boost-root/status directory and running the tests for *at least one* library, but preferably all of them. Thank you for paying attention. -- -- Grafik - Don't Assume Anything -- Redshift Software, Inc. - http://redshift-software.com -- rrivera/acm.org (msn) - grafik/redshift-software.com -- 102708583/icq - grafikrobot/aim,yahoo,skype,efnet,gmail

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[iostreams] File times on POSIX systems
by Markus Schöpflin 29 Jul '08

29 Jul '08

Hello, currently iostreams has a number of failures on POSIX systems because of the use of the non-existent function futimes(). futimes() conforms to 4.2BSD and is unknown to POSIX, which only has utime() to set file access and modification times. Unfortunately utime() works in term of path names and not file descriptors, and I'm not aware of any suitable replacement, so perhaps the interface for the functionality in question needs to be changed. Regards, Markus

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[spirit] files missing on trunk
by Juergen Hunold 29 Jul '08

29 Jul '08

Hi ! It seems that the files changed/added in revision 47602 (see http://svn.boost.org/trac/boost/changeset/47602 ) are missing from trunk and are causing the regression tests to fail. (at least locally here...) Yours, Jürgen -- * Dipl.-Math. Jürgen Hunold ! Ingenieurgesellschaft für * voice: ++49 511 262926 57 ! Verkehrs- und Eisenbahnwesen mbH * fax : ++49 511 262926 99 ! Lister Straße 15 * juergen.hunold(a)ivembh.de ! www.ivembh.de * * Geschäftsführer: ! Sitz des Unternehmens: Hannover * Prof. Dr.-Ing. Thomas Siefer ! Amtsgericht Hannover, HRB 56965 * PD Dr.-Ing. Alfons Radtke !

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[Serialization] [1.36.0] extended_type_info_typeid::destroy should use boost::serialization::access
by Doug Gregor 28 Jul '08

28 Jul '08

Somewhere between Boost 1.35.0 and 1.36.0, Boost.Serialization lost the ability to (de-)serialize a pointer to a class with a protected or private destructor. The problem is in extended_type_info_typeid::destroy, which tries to delete a pointer directly rather than using boost::serialization::access::destroy. This is unfortunate, because it's breaking a use of the serialization library in VTK. The patch below fixes the problem and passes all regression tests. Okay to commit to trunk and the 1.36.0 branch? - Doug Index: extended_type_info_typeid.hpp =================================================================== --- extended_type_info_typeid.hpp (revision 47849) +++ extended_type_info_typeid.hpp (working copy) @@ -28,6 +28,7 @@ #include <boost/type_traits/is_polymorphic.hpp> #include <boost/type_traits/remove_const.hpp> +#include <boost/serialization/access.hpp> #include <boost/serialization/singleton.hpp> #include <boost/serialization/extended_type_info.hpp> #include <boost/serialization/factory.hpp> @@ -113,7 +114,7 @@ public: } } void destroy(void const * const p) const{ - delete static_cast<T const *>(p) ; + boost::serialization::access::destroy(static_cast<T const *>(p)); } };

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Question about boost.extension
by Noah Roberts 28 Jul '08

28 Jul '08

Does this library address the problems associated with calling conventions when using different compilers? Can I compile an application with one compiler and allow users to provide plugins compiled with another? I have my doubts that this is even possible to solve, but I ask anyway.

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[filesystem] two-minute tutorial uses deprecated functions
by Michael Marcin 28 Jul '08

28 Jul '08

The two-minute tutorial section of the filesystem documentation calls leaf() from a dereferenced directory_iterator. The reference documentation shows that dereferencing a directory_iterator yields a directory_entry but the reference documentation for directory_entry shows no leaf member. Eventually I had to track it down in the source code and found out that leaf does exist but is deprecated and not documented. It is probably bad to have the introduction to a library use undocumented functions. Thanks, Michael Marcin

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data_binding library for boost... Any interest?
by Brian Davis 27 Jul '08

27 Jul '08

I looked through boost and if there is a library or facility for data binding in boost I could not find it... So I created and am submitting a simple example for review. Please take a look and give some feedback. I understand that there is quiet a process of review before a library is included in boost. If there is interest or if there is already on going work on the concept than I am interested in helping. Here goes: Data binding should allow for 1 value of primitive type to be changed in code and have 1 to N values be modified based on the event and optional conversion functions. i.e. fanout should be allowed Data binding should allow for cascading changes. Where a->b->c->d where -> represents a binding link when 'a' changes 'c', 'b', and 'd' should change. Data binding should be recursion save where a->b->c->a where a change in 'a' causes a change in 'c', but will not cause a recursive change in 'a' creating a recursive loop. Data binding would be useful in the dataflow library and for work being done on cppgui or for that fact any UI development. This is my first submittal to this list so please bear with me. I have taken the liberty to add the boost license to this code... so it is boost's if the project so chooses to incorporate or enhance the concept. I am not the originator of data binding concept and make no claim to this. I am only providing a simple example for discussion and hopefull inclusion of data binding concept in boost and ....ultimately modify the C++ compiler to provide for a lighter weight solution (events based on modifications of integral types) - Ouch ... yes I know what I am asking here... see the last part of the example output for why I ask this. // Start snip bind_value.hpp ======================================= // // (C) Copyright Brian Davis. // // Distributed under the Boost Software License, Version 1.0. (See accompanying // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) // // Revision history: // 19 July 2008 // Created - to support and assist in dataflow and dataflow concepts // // This is not currently part of boost! The only reason for the above copyright is to // keep these concepts part of the boost development. boost::data_binding is not // officially part of boost. The goal of this demo code is to elaborate on data binding // and give a simple implementation and an example on how the concept can be applied within C++. #ifndef BOOST_DATA_BINDING_HPP #include <boost/cast.hpp> #include <boost/function.hpp> #include <boost/bind.hpp> #include <boost/foreach.hpp> #include <vector> namespace boost { namespace data_binding { template < class T1, class T2> class bind_values; template <class T> class value { friend class bind_values< class T1, class T2>; public: typedef boost::function< T& (T&) > set_value_function; std::vector<set_value_function> set_value_functions; T& mv_value; // To prevent infinite recursion on a group of three linked variables a->b->c->a. bool mv_entered; protected: private: public: value( T& invalue ) : mv_value( invalue ){ mv_entered = false; }; // Sets require action event handling to update value of binded type.. gets are transparent value& operator=( T& rhs ) { if( set_value_functions.size() && !mv_entered ) { mv_entered = true; BOOST_FOREACH( set_value_function set_value, set_value_functions ) { mv_value = set_value( rhs ); } } else { // Otherwise simple type cast convert mv_value = boost::numeric_cast<T>( rhs ); } mv_entered = false; return *this; } value& operator=( T rhs ) { if( set_value_functions.size() && !mv_entered ) { mv_entered = true; BOOST_FOREACH( set_value_function set_value, set_value_functions ) { mv_value = set_value( rhs ); } } else { // Otherwise simple type cast convert mv_value = boost::numeric_cast<T>( rhs ); } mv_entered = false; return *this; } void add_set_function( set_value_function set_function ) { set_value_functions.push_back( set_function ); } T& operator&( value<T>& value ) { return value.mv_value; } protected: private: }; template < class T1, class T2> class bind_values { friend class value<T1>; friend class value<T2>; public: typedef T1 type1; typedef T2 type2; typedef boost::function< T1& (T1, T2)> convert_to_function; typedef boost::function< T2& (T2, T1)> convert_from_function; convert_to_function convert_to; convert_from_function convert_from; protected: value<T1>& mv_value1; value<T2>& mv_value2; private: public: bind_values ( value<T1>& value1, value<T2>& value2, convert_to_function convertTo, convert_from_function convertFrom ) : convert_to(convertTo), convert_from(convertFrom), mv_value1( value1 ), mv_value2( value2 ) { // Hook up set for value 1 mv_value1.add_set_function( boost::bind( &bind_values::set_value1, this, _1 ) ); // Hook up set for value 2 mv_value2.add_set_function( boost::bind( &bind_values::set_value2, this, _1 ) ); } bind_values( value<T1>& value1, value<T2>& value2 ) : mv_value1( value1 ), mv_value2( value2 ) { // Hook up set for value 1 mv_value1.set_value = boost::bind( &bind_values::set_value1, _1 ); // Hook up set for value 2 mv_value2.set_value = boost::bind( &bind_values::set_value2, _1 ); } protected: T1& set_value1( T1& value ) { if( convert_from ) { // Convert and set value 2 mv_value2 = boost::numeric_cast<T2>( convert_from( mv_value2.mv_value, value ) ); } else { // Otherwise simple type cast convert mv_value2 = boost::numeric_cast<T2>( value ); } // return the value unmodified to the original container return value; } T2& set_value2( T2& value ) { if( convert_to ) { // Convert and set value 1 mv_value1 = boost::numeric_cast<T1>( convert_to( mv_value1.mv_value, value ) ); } else { // Otherwise simple type cast convert mv_value1 = boost::numeric_cast<T1>( value ); } // return the value unmodified to the original container return value; } private: }; } } // namespace boost::data_binding template <class T> std::ostream& operator<<( std::ostream& os, boost::data_binding::value<T>& rhs ) { os << rhs.mv_value;; return os; } #endif // end snip bind_value.hpp ======================================= // Start snip bind_value_test.hpp ======================================= // // (C) Copyright Brian Davis. // // Distributed under the Boost Software License, Version 1.0. (See accompanying // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) // // Revision history: // 19 July 2008 // Created - to support and assist in dataflow and dataflow concepts // // This is not currently part of boost! The only reason for the above copyright is to // keep these concepts part of the boost development. boost::data_binding is not // officially part of boost. The goal of this demo code is to elaborate on data binding // and give a simple implementation and an example on how the concept can be applied within C++. #include <iostream> #include <boost/cstdint.hpp> #include <boost/bind.hpp> #include <boost/data_binding/bind_value.hpp> #define MAX_CELSIUS 100 #define MIN_CELSIUS -17.8 #define MAX_RAW_SENSOR_COUNTS 4095 // use of a class is not necessary it is only shown to prove it is possible. It may // make more sense just to have conversion functions class AClass_That_Is_A_Converter { public: protected: boost::data_binding::value<boost::uint32_t> rawCelsiusCountsFromSensor; boost::data_binding::value<float> calibratedCelsiusDataFromSensor; boost::data_binding::value<float> calibratedFahrenheit; boost::uint32_t rawSensorValue; float fahrenheit; float celsius; boost::data_binding::bind_values<float, boost::uint32_t> mv_celsiusToSensorBinder; boost::data_binding::bind_values<float, float> mv_celsiusToFahrenheitBinder; private: public: AClass_That_Is_A_Converter( void ) : rawCelsiusCountsFromSensor(rawSensorValue), calibratedCelsiusDataFromSensor(celsius), calibratedFahrenheit(fahrenheit), mv_celsiusToSensorBinder ( calibratedCelsiusDataFromSensor, rawCelsiusCountsFromSensor, boost::bind( &AClass_That_Is_A_Converter::convertCelsiusRawToCalibrated, this, _1, _2 ), boost::bind( &AClass_That_Is_A_Converter::convertCelsiusCalibratedToRaw, this, _1, _2 ) ), mv_celsiusToFahrenheitBinder ( calibratedCelsiusDataFromSensor, calibratedFahrenheit, boost::bind( &AClass_That_Is_A_Converter::convertFahrenheitToCelsius, this, _1, _2 ), boost::bind( &AClass_That_Is_A_Converter::convertCelsiusToFahrenheit, this, _1, _2 ) ) {} virtual ~AClass_That_Is_A_Converter( void ){} void test( void ) { std::cout << "Starting test of data binding" << std::endl; try { std::cout<< "Note raw temp represents the raw value of an Analog to Digital Converter" << std::endl; std::cout<< "The range is from 0-4095 which represents -17.8 - 100 degrees on the Celsius" << std::endl; std::cout<< "scale and 0 - 212 degrees on the Fahrenheit" << std::endl; std::cout<< "Setting calibratedFahrenheit to 70.0 degrees fahrenheit" << std::endl; std::cout<< "calibratedFahrenheit = 70.0f;" << std::endl; calibratedFahrenheit = 70.0f; std::cout << "What does the celsius value contain? ... should be ~21.1" << std::endl; showValues(); std::cout << "Now change the raw sensor value and see what happens to Celsius and Fahrenheit" << std::endl; std::cout<< "rawCelsiusCountsFromSensor = 4095;" << std::endl; rawCelsiusCountsFromSensor = 4095; std::cout << "Celsius should equal ~100" << std::endl; std::cout << "Fahrenheit should equal ~212" << std::endl; showValues(); std::cout << "Now change celsius see what happens to raw and farenheit" << std::endl; std::cout<< "calibratedCelsiusDataFromSensor = 32.2;" << std::endl; calibratedCelsiusDataFromSensor = 32.2; std::cout << "Fahrenheit should equal ~90 degress" << std::endl; showValues(); std::cout << "Note changing original values will not have any affect in C++ " << std::endl; std::cout << "this makes me sad :-( as a class wrapper and operator overloading" << std::endl; std::cout << "is necessary... without changing the compiler... hint.... hint..." << std::endl; std::cout << "fahrenheit = 10;" << std::endl; fahrenheit = 10; showValues(); std::cout << "No change in values :-( !!!" << std::endl; // Note one to many fanout is possible and the example shows 1 to 2 fanout with Celsius // fanning out to Raw and Fahrenheit values. A more advanced implementation is also possible // which includes the use of the lamda library and place holders. This is just a simple // example which I hope will "prime the pump" for work on a data_binding library with in // the Boost development. Most direct use for this library is within data_flow library. // Another use is within the cppgui library which would allow modification of data to directly // affect values of UI controls and display values. } catch( std::exception& ex ) { std::cout << "Failed with exception: " << ex.what(); } std::cout << "End of data binding test" << std::endl; } void showValues( void ) { std::cout << std::endl; std::cout << "Fahrenheit : " << calibratedFahrenheit << std::endl; std::cout << "Celsius : " << calibratedCelsiusDataFromSensor << std::endl; std::cout << "Raw Temp To/From Sensor A/D converter : " << rawCelsiusCountsFromSensor << std::endl; std::cout << std::endl; std::cout << "fahrenheit : " << fahrenheit << std::endl; std::cout << "celsius : " << celsius << std::endl; std::cout << "rawSensorValue : " << rawSensorValue << std::endl; std::cout << std::endl; std::cout << "====================================================================" << std::endl; } protected: float& convertFahrenheitToCelsius ( float& celsius , float& fahrenheit ) { return celsius = ((fahrenheit - 32.0) * 5.0) / 9.0; } float& convertCelsiusToFahrenheit ( float& fahrenheit, float& celsius ) { return fahrenheit = celsius * (9.0 / 5.0) + 32.0; } float& convertCelsiusRawToCalibrated ( float& calibratedValue, boost::uint32_t& rawValue ) { return calibratedValue = ( MAX_CELSIUS - MIN_CELSIUS ) * (rawValue / MAX_RAW_SENSOR_COUNTS) + MIN_CELSIUS; } boost::uint32_t& convertCelsiusCalibratedToRaw ( boost::uint32_t& rawValue, float& calibratedValue ) { // Raw is from 0 to 4095 ( a 12 bit number of an // Analog to Digital converter // map zero (fahrenheit) to water boiling to raw value of 4095 return rawValue = MAX_RAW_SENSOR_COUNTS * ( calibratedValue - MIN_CELSIUS) / ( MAX_CELSIUS - MIN_CELSIUS ); } private: }; int main(int argc, char **argv) { AClass_That_Is_A_Converter anExampleOfDataBinding; anExampleOfDataBinding.test(); } // end snip bind_value_test.hpp ======================================= // Start snip program output ======================================= Starting test of data binding Note raw temp represents the raw value of an Analog to Digital Converter The range is from 0-4095 which represents -17.8 - 100 degrees on the Celsius scale and 0 - 212 degrees on the Fahrenheit Setting calibratedFahrenheit to 70.0 degrees fahrenheit calibratedFahrenheit = 70.0f; What does the celsius value contain? ... should be ~21.1 Fahrenheit : 70 Celsius : 21.1111 Raw Temp To/From Sensor A/D converter : 1352 fahrenheit : 70 celsius : 21.1111 rawSensorValue : 1352 ==================================================================== Now change the raw sensor value and see what happens to Celsius and Fahrenheit rawCelsiusCountsFromSensor = 4095; Celsius should equal ~100 Fahrenheit should equal ~212 Fahrenheit : 212 Celsius : 100 Raw Temp To/From Sensor A/D converter : 4095 fahrenheit : 212 celsius : 100 rawSensorValue : 4095 ==================================================================== Now change celsius see what happens to raw and farenheit calibratedCelsiusDataFromSensor = 32.2; Fahrenheit should equal ~90 degress Fahrenheit : 89.96 Celsius : 32.2 Raw Temp To/From Sensor A/D converter : 1738 fahrenheit : 89.96 celsius : 32.2 rawSensorValue : 1738 ==================================================================== Note changing original values will not have any affect in C++ this makes me sad :-( as a class wrapper and operator overloading is necessary... without changing the compiler... hint.... hint... fahrenheit = 10; Fahrenheit : 10 Celsius : 32.2 Raw Temp To/From Sensor A/D converter : 1738 fahrenheit : 10 celsius : 32.2 rawSensorValue : 1738 ==================================================================== No change in values :-( !!! End of data binding test // End snip program output ======================================= This was done to assist Sjepan Rajko in his work on the dataflow library (he beat me to it :-) ). Dataflow provides the event model data_binding provides the means to do data conversion between events. Brian.

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[implicit_cast]: No docs?
by Sean Hunt 27 Jul '08

27 Jul '08

implicit_cast doesn't seem to have any documentation anywhere that I can find. Is this intentional, or merely an oversight? Sean Hunt

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[math][bcp] rational.hpp doesn't get processed well by bcp
by Stjepan Rajko 26 Jul '08

26 Jul '08

Hello, boost/math/tools/rational.hpp (in trunk, at least) includes files by constructing a macro, e.g.: # define BOOST_HEADER() <BOOST_JOIN(boost/math/tools/detail/polynomial_horner1_, BOOST_MATH_MAX_POLY_ORDER).hpp> # include BOOST_HEADER() bpc doesn't seem to pick up dependencies that are included in this fashion - is it possible to include something into rational.hpp to serve as a hint to bcp on what all files might be included? Thanks, Stjepan

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How do we handle copyrights here? (Fwd: blanket-permission.txt)
by Daryle Walker 26 Jul '08

26 Jul '08

I noticed that some of my code is showing up in the inspection report. Specifically, "boost/math/common_factor_rt.hpp" and a lot of Boost.Rational. When I looked at the former file, I remembered why I never corrected those files before: I share the copyright for those files with Paul Moore, and I've never been able to find him again. (See my latest attempt below.) Unless someone else here knows how to contact him (if he's still alive), what do we do? Do we special-case those files to be skipped by the inspector? Do we try re- implementing the interface in those files so they won't contain Paul's work? Begin forwarded message: > From: "Paul Moore" <paul.moore(a)centrify.com> > Date: July 25, 2008 2:15:06 PM EDT > To: "Daryle Walker" <darylew(a)hotmail.com> > Subject: RE: [boost] blanket-permission.txt > > That's not me > > -----Original Message----- > From: Daryle Walker [mailto:darylew@hotmail.com] > Sent: Friday, July 25, 2008 11:08 AM > To: Paul Moore > Subject: [boost] blanket-permission.txt > > I got this address from looking at old Boost mailing list posts. If > you're that same Paul Moore, I wonder if you would consider adding > your > name to the BOOST_ROOT/more/blanket-permission.txt list, to allow any > material that has your copyright, in whole or in part, be shifted over > to the Boost Software License. > > I ask this because I noticed that some files I maintain are under a > list > with license check problems. (The Boost files are run over with a > batch > script that looks for such administrative problems.) I wondered why I > never fixed that problem, then when I read the file I remembered > that I > never changed it because I couldn't find you to ask permission. (The > file in particular is "boost/math/ common_factor_rt.hpp", which we > share > copyright on.) -- Daryle Walker Mac, Internet, and Video Game Junkie darylew AT hotmail DOT com

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Help with deficient compilers?
by Daryle Walker 26 Jul '08

26 Jul '08

I need help with fixing code in BOOST_ROOT/libs/integer/test/ integer_test.cpp. It works fine on my computer, but other ones are giving errors. I have some guesses on what's wrong, but I need suggestions on what the fixes should be. 1. I have a custom meta-function like: //========================= typedef boost::mpl::vector<unsigned char, unsigned short, unsigned int, unsigned long long> distinct_unsigned_types; typedef boost::mpl::transform< distinct_unsigned_types, boost::make_signed< boost::mpl::_1 > >::type distinct_signed_types; // List the digit counts for each integral type template < typename T > struct digits_of : boost::mpl::int_< std::numeric_limits<T>::digits > { }; typedef boost::mpl::transform< distinct_unsigned_types, digits_of< boost::mpl::_1 > >::type distinct_integral_bit_counts; //========================= I noticed that supplied meta-functions, like boost.make_unsigned, use macros in their implementations, instead of the straight implementation I use in digits_of. Now MPL says that its machinery will make sure that straight implementations work. However, I don't think it's successful on deficient compilers. Maybe I should structure digits_of with all the work-around macros. How? (I don't want to just look at the headers and guess how they work.) 2. I don't think I have SFINAE selection correct: //========================= #ifndef BOOST_NO_SFINAE template < typename ValueT, template<ValueT> class Tmpl, ValueT Value > bool print_out_template( Tmpl<Value> const &, ValueT setting, char const *template_pre_name, char const *template_post_name, typename Tmpl<Value>::type *unused = 0 ) { // Too bad the type-id expression couldn't use the compact form "*unused", // but type-ids of dereferenced null pointers throw by order of C ++ 2003, // sect. 5.2.8, para. 2 (although the result is not conceptually needed). PRIVATE_SHOW_MESSAGE( "This is " << template_pre_name << setting << template_post_name << " specialization, with type '" << typeid(typename Tmpl<Value>::type).name() << "'." ); return true; } template < typename ValueT, typename T > bool print_out_template( T const &, ValueT setting, char const *template_pre_name, char const *template_post_name ) { PRIVATE_SHOW_MESSAGE( "Looking for " << template_pre_name << setting << template_post_name << " specialization? It doesn't exist." ); return false; } #else #error "These tests cannot work without Substitution-Failure-Is-Not- An-Error" #endif //========================= The BOOST_NO_SFINAE guards didn't help, compilers still choked on this code. (I guess I'll remove those guards later.) I think that any type that doesn't have an inner "type" will only choose the false- return case. On my computer, types with an inner "type" will choose the true return case, with that case being given priority. The reports are giving errors where, when given a type with an inner "type", the two cases are considered equal, leading to an ambiguity error. How do I restructure this code? -- Daryle Walker Mac, Internet, and Video Game Junkie darylew AT hotmail DOT com

1 0

Boost.Spirit based C++ parser
by Bruce Trask 26 Jul '08

26 Jul '08

// note to moderator, I am reposting as my original post seemed have ended up buried in "1.36 documentation" thread. Ok to repost below? Hi, I came across this wiki discussion: http://www.crystalclearsoftware.com/cgi-bin/boost_wiki/wiki.pl?BoostSpiritC… Did this ever move forward or materialize? Thanks in advance. Regards, Bruce

1 0

boost::coroutines and boost::asio
by atkinson julian 26 Jul '08

26 Jul '08

Hi, the combination of asio and coroutines would seem to represent a little bit of magic (layering a linear code model over an async event framework and without the attendant issues involved in multithreading). However the coroutine library seems to be exception throwing in an unanticipated way when performing a wait on a future<> during the execution of an asio async operation. I am following the documention and am reasonably familiar with asio from other projects - but have only just worked through some of the examples from the coroutines documention. i am using the vault freeze version of coroutines from 2006 - i understand from perusing these lists that the library author is currently rewritting boost::coroutine around a continuation framework to simplify and in the hope that the library may be an official boost inclusion. Much kudos for contributing to c++ in a significant way ;-) the documentation seems to have some errors http://www.crystalclearsoftware.com/soc/coroutine/coroutine/asio.html - guidance is given to use shared_coroutine in preference to coroutine in asio context although this is not present in the example - asio uses the boost::system error classes in the boost namespace when not freestanding - the example calls wait() on source which is a socket type rather than a future I have attempted to work up an example which looks logical - but cant get around the throw that occurs at /boost/coroutine/detail/context_base.hpp:213 // linux 2.6.23, g++ (GCC) 4.1.2 // g++ -g main.cpp -lboost_coroutine-mt -lboost_system-mt #include <iostream> #include <boost/bind.hpp> #include <boost/ref.hpp> #include <boost/coroutine/coroutine.hpp> #include <boost/coroutine/generator.hpp> #include <boost/coroutine/future.hpp> #include <boost/asio.hpp> namespace coro = boost::coroutines; using namespace coro; typedef boost::asio::io_service service_type; //typedef coro::coroutine< void()> foo_coroutine_type; //typedef coro::coroutine< void( service_type &service)> foo_coroutine_type; typedef coro::shared_coroutine< void( service_type &service)> foo_coroutine_type; void foo( foo_coroutine_type::self &self, service_type &service) { typedef boost::system::error_code error_type; typedef boost::asio::ip::tcp::resolver::query query_type; typedef boost::asio::ip::tcp::resolver::iterator iterator_type; boost::asio::ip::tcp::resolver resolver( service); query_type query( "www.boost.org", 80 ); coro::future< error_type, iterator_type> future( self); resolver.async_resolve( query, coro::make_callback( future)); assert( !future); // wait throws here --> /boost/coroutine/detail/context_base.hpp:213 coro::wait( future); assert( future); error_type &error = future->get< 0>(); if( error) std::cout << "error resolving " << error.message() << std::endl; else { iterator_type ip = future->get< 1>(); while( ip != iterator_type()) std::cout << ip->endpoint() << std::endl; } } int main() { service_type service; foo_coroutine_type cfoo( boost::bind( &foo, _1, boost::ref( service))); cfoo(); // service.post( boost::bind( &foo_coroutine_type::operator(void ), &cfoo)); service.run(); }

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Phoenix in 1.35.0
by Robert Jones 26 Jul '08

26 Jul '08

My understanding of the state of play with Phoenix is that the lovely Phoenix 2.0 is part of the not-yet-released Boost 1.36.0, and that the current release of Boost, 1.35.0 hosts Phoenix 1.2. Phoenix 2.0 has lovely documentation at http://spirit.sourceforge.net/dl_docs/phoenix-2/libs/spirit/phoenix/doc/htm… but the corresponding documentation for V1.2, at http://www.boost.org/doc/libs/1_35_0/libs/spirit/phoenix/index.html is buried inside the Spirit docs, and is not nearly as good as the v2.0 documentation. In particular the v1.2 docs are very quiet about specific include file paths, which have also changed significantly for v2.0. Is there anything I've missed in all this? ----------- Also looking through the documentation of Boost libraries in general, the quality varies widely. Am I correct in believing this is due to whether the various library authors have found time to write quality documentation? Regards, Rob. -- ACCU - Professionalism in programming - http://www.accu.org

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[1.36.0] Beta release imminent
by Beman Dawes 26 Jul '08

26 Jul '08

The plan is to build the 1.36.0 beta release Sunday. Developers who have permission to make last minute fixes and docs updates should commit those changes by midnight Saturday, UTC. --Beman

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circular_buffer update - merge with 1.36?
by Jan Gaspar 26 Jul '08

26 Jul '08

Hi, I have updated the circular_buffer library in the trunk (I was not able to do it earlier as I have been very busy in the past few weeks). Here are the release notes: - Changed behaviour of the circular_buffer(const allocator_type&) constructor. Since this version the constructor does not allocate any memory and both capacity and size are set to zero. - Added new methods is_linearized() and rotate(const_iterator). - Fixed bugs: #1987 Patch to make circular_buffer.hpp #includes absolute. #1919 Default constructed circular buffer throws std::bad_alloc. #1852 Copy constructor does not copy capacity. The tests passed on trunk (I made the update on Wednesday so it was included in the Friday's report). Not sure it is possible at this stage but it would be great if I can merge it into the release. There was a merge done by Thorsten several days ago but it didn't include the documentation changes (I don't blame him, he did the best he could). So now there is a discrepancy between the code and the documentation in the release branch. Jan __________________________________________________________ Not happy with your email address?. Get the one you really want - millions of new email addresses available now at Yahoo! http://uk.docs.yahoo.com/ymail/new.html

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[spirit2] User experience and concerns
by Zach Laine 25 Jul '08

25 Jul '08

I've been eagerly anticipating the new version of Spirit ever since BoostCon 07. I've been using the code from the release branch to play around with it a bit, and I have a few concerns about its usability. I specifically have been using it to replace some rather ugly parsing code in an existing library. This code parses tagged text for use in a GUI, e.g. "Some text, <i>partially italicized</i>." This is very similar to the mini_xml example in the docs, so I used that as a starting point. There are some key differences between the simple_xml format and my needs, and as soon as I started deviating from the example too far I started having troubles. The differences are: 1) A tag can have parameters, and they don't look exactly like xml attributes, e.g. "<color 255 255 255 127>translucent white text</color>". 2) The "<pre>" tag is special. It turns off recognition of all future tags until the next "</pre>" end-tag is seen. 3) Stray "<" characters in the non-tag parts of the input are fine. 1) and 2) were fairly straightforward to implement as changes to simple_xml, but 3) has so far eluded me. 3) requires that all ">" sequence operators be changed to ">>" in the tagged-text parsing, so that more extensive backtracking can be done to ensure a stray "<" is not actually part of a tag. I'll summarize briefly the problems I had in terms of surprises, counterintuitive interfaces, and compilation failures that left me nonplussed. I've attached the full source (only one file, called "test.cpp"), and there are numerous comments in that code that are more direct and explicit. All my efforts were done with various recent revisions, most recently HEAD at the time of this writing -- 47802. Everything was done on a Linux box with GCC 4.1.2. - Auto-assignment seems to work fine for simple expressions, and fail for only slightly more complicated ones that the user would not expect. See Line 61. - Alternative expressions do not seem to work in a greedy fashion in all cases. See Line 70. - The rules for whether a character parser has an attribute or not are sure to seem arbitrary to everyday users. See Line 83. - In at least one case, a rule whose attribute was explicitly declared to be a type I defined (TaggedText) stubbornly insisted its attribute was std::string. See line 117. - Changing the ">" sequence operators (which seem to work nicely with "%=") to ">>" sequence operators makes the use of "%=" produce compilation errors. This forces one to resort to using semantic actions like in Spirit 1. See Line 124. On a different note, two of the Qi examples do not compile. They are actions and calc3_lexer. I did not try to compile the others (Karma, etc.). All tests (for everything -- not just Qi) pass. Zach Laine

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[concept_check] Problem with concept checks and overloads
by Bruno Lalande 25 Jul '08

25 Jul '08

Hello, Barend and I have been facing a problem while integrating concept checks into the Geometry Library. In order to simplify the problem, I reduced it to a very simple test case: template <typename T> struct foo {}; template <class X> struct DummyConcept { typedef typename X::something something; }; template<typename T> BOOST_CONCEPT_REQUIRES(((DummyConcept<T>)), (void)) func(T&) { std::cout << "first overload" << std::endl; } template<typename T> void func(foo<T>) { std::cout << "second overload" << std::endl; } int main() { func(foo<int>()); return 0; } This code doesn't compile because the compiler tries to check foo<int> against the DummyConcept, even though it's supposed to select the second overload, which doesn't carry any concept requirement. Removing the check makes it compile and a run displays "second overload". If I put back the check and add a "typedef void something" into foo, it compiles and displays the same thing. So I deduce that, more generally, a compiler compiles the return type of every candidate overload before selecting the right one, and that's why we have this issue with concept checking. So I have 2 questions: - would there be any way to differ the check until after the right overload has been selected, thus doing the check only for that overload? - if no, is there a better workaround than replacing BOOST_CONCEPT_REQUIRES by a simple BOOST_ASSERT inside the function? Thanks in advance. Bruno

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Re: [boost] [1.36] release blurb? [plus a tip for the authors]
by JOAQUIN M. LOPEZ MUÑOZ 25 Jul '08

25 Jul '08

_______________________________________ De: boost-bounces(a)lists.boost.org [boost-bounces(a)lists.boost.org] En nombre de Daniel James [daniel_james(a)fmail.co.uk] Enviado el: lunes, 21 de julio de 2008 20:46 Para: boost(a)lists.boost.org Asunto: Re: [boost] [1.36] release blurb? > > On 21/07/2008, JOAQUIN M. LOPEZ MUÑOZ <joaquin(a)tid.es> wrote: > > > > I wonder whether we already have some place to begin adding content > > to the 1.36 release notes--you know, listing the new libraries and > > significant updates. > > http://svn.boost.org/svn/boost/website/public_html/beta/feed/history/boost_… > > if you're not comfortable with quickbook, just send what you want to > add to the list. I've just added an entry for multi_index, hopefully I haven't messed anything, would be grateful if you could take a look. Also, I tidied up the previous material in the page according to the following rules, which AFAICS have governed the composition of previous release blurbs: 1. Libraries are listed in alphabetical order. 2. Besides the dedicated entry, the lib name should be added to the [purpose] section at the beginning of the page. Maybe it'd make sense to add these rules as a reminder comment at the beginning of the page (provided Quickbook has some form of comment)? Best, Joaquín M López Muñoz Telefónica, Investigación y Desarrollo

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Mac OS universal builds: testers needed
by Mat Marcus 25 Jul '08

25 Jul '08

I've made a number of changes to my universal-binary supporting darwin.jam patch (shipping with the Adobe Source Library) in order to address the concerns raised by Rene and others at http://svn.boost.org/trac/boost/ticket/989 : My current version supports invocations like: bjam architecture={combined,x86,power} link={shared,static} address-model={64,32} That is, universal builds are now supported, along with 64 bit builds. I'd like to ask for the help from a few volunteers who'd be willing to test it out, before I submit my patch for consideration. Anyone interested in helping me test it? If so, please contact me off list and I'll send you a couple of boost build files to replace. I still have a bit of cleanup to do. Specifically, on the mac, if a build doesn't specify an -arch parameter, the architecture (and perhaps the address model) of the host machine is used. I'm not really comfortable with the same folder path meaning different things on different machines. So, I plan to do something like the following in darwin.jam (in invented pseudo code) SWITCH(on result of /usr/bin/arch) { # host machine's architecture CASE(ppc) use <architecture>power/<address-model>32 as the default CASE(i386) use <architecture>x86/<address-model>32 as the default CASE(ppc64) use <architecture>power/<address-model>64 as the default CASE(x86_64) use <architecture>x86/<address-model>64 as the default DEFAULT error, unknown arch Thanks, Mat

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[test] Gennadiy, did you notice...?
by Daryle Walker 25 Jul '08

25 Jul '08

This is about the Boost.Test library files just uploaded to our Subversion repository, revision 47797. I like the fact that support headers are now automatically #included, but I noticed that "boost/ test/unit_test_suite.hpp" and "boost/test/test_case_template.hpp" #include each other. (The #include guards prevent infinite recursion.) You may want to fix that. -- Daryle Walker Mac, Internet, and Video Game Junkie darylew AT hotmail DOT com

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[test] Broken header (via indirect #includes)
by Daryle Walker 25 Jul '08

25 Jul '08

I was fixing up a test file, and the compilation failed complaining that "'type' is not a member of 'boost'" within the innards of a "BOOST_AUTO_TEST_CASE_TEMPLATE" line. I figured out that the error was referring to the obscure boost::type class template in "boost/ type.hpp". I included that file, and then the compiler complained saying that "'template_test_case_gen' is not a member of 'boost::unit_test::ut_detail'." Doing a multiple-file search, I realized the true problem. 1. BOOST_AUTO_TEST_CASE_TEMPLATE is #defined in "boost/test/ unit_test_suite.hpp" 2. This template depends on boost::type and boost::unit_test::ut_detail::template_test_case_gen 3. template_test_case_gen is defined in "boost/test/ test_case_template.hpp", which happens to #include "boost/type.hpp" 4. Neither of the appropriate headers are directly #included in "unit_test_suite.hpp" 5. I guess that one or both headers were indirectly #included in "unit_test_suite.hpp", but that indirect header purged the headers I needed, and the author _forgot_ that another header was counting on the old indirect #include. I worked around the problem for now by directly #including "boost/ test/test_case_template.hpp" in my test file. But I shouldn't have to do this. Worse, this has happened before with Boost.Test, in regards to the floating point comparison tests. Those test macros called a function that wasn't in the same header, nor #included; i.e. the user has to add an extra #include for the floating-point test macros to work. The floating-point incident was a deliberate design decision, but I guess that my problem here was caused by accident. The point: DIRECTLY #include everything a macro needs in that macro's header. I'm sick & tired of hunting all the extra headers I need. Worse, I'll have to re-hunt when my test program craps out if/when the author re-arranges all the macros & headers. My point [5] is only a guess because I wasted two hours searching the trac/subversion site for where & when the author broke the build. I didn't find it, and I figured that I shouldn't have to. When you fix this, let me know so I can remove the extra #include from my test file. (Apologies in advance if the real problem is that my subversion working copy is severely fried.) -- Daryle Walker Mac, Internet, and Video Game Junkie darylew AT hotmail DOT com

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