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[Phoenix] documentation feedback
by John Dlugosz 01 Jun '10

01 Jun '10

<http://www.boost.org/doc/libs/1_43_0/libs/spirit/phoenix/doc/html/phoenix/b…> What it returns instead is another function, a lambda function --another black box. The two hyphens should be an em-dash, and the space (of lack of) the same on either side. I suggest a "thin space" on either side, or no space. Also, the generated HTML is missing the <!DOCTYPE> declaration <http://www.boost.org/doc/libs/1_43_0/libs/spirit/phoenix/doc/html/phoenix/o…> Table 1.2 names "Container", but that is not in the four-layer chart of modules above. <http://www.boost.org/doc/libs/1_43_0/libs/spirit/phoenix/doc/html/phoenix/p…> Evaluating a Value cout << val(3)() << val("Hello World")(); prints out "3 Hello World". Where does the extra space come from? Should that be "3Hello World"? (Two instances in file) Here, we want the first function argument, x, to be mutable. The 'x' is not marked with tt and identifier like other such things are. <http://www.boost.org/doc/libs/1_43_0/libs/spirit/phoenix/doc/html/phoenix/c…> where ftor is an instance of factorial_impl is missing tt/identifier in two places composite is simply a function object expecting a single argument of the containers value_type ditto, "value_type" where arg1 is replaced by the container's element. ditto, "arg1" the if_else pseudo function is provided for this purpose ditto, "if_else" are passed on to STL's for_each function. ditto, "for_each". Many others, I'll stop listing them. 2. Unary operators are lazily evaluted if their argument is an actor object. Is grammatically incorrect (it implies that all the operators are sharing a single argument) and it would be better worded to be consistent with the tense of the other items in the list, specifically #1. It also contains a spelling error ("evaluted"). I would suggest "A unary operator will be lazily evaluated with its operand is an actor object." ifelse statment (Header level 4) I think the Docbook exporter got confused. Just look at the page in a web browser! I think you meant to write "if_else_" and it took the underscore as a formatting directive, since it appears to underscore the rest of the word and has no space or underscore characters. dowhile Statement (Header) ditto. It is again very similar to the C++ for statement. Take note that the init_statement, conditional_expression and stepstatement are separated by the comma instead of the semi-colon and each must be present (i.e. `for(,,)` is invalid). Besides missing the tt/identifier in several places, I think it originally said "... step_ statement ... for_(,,)" and the underbars got taken as underling everything between them. The backticks around the "for" expression should be tt formatting instead. <http://www.boost.org/doc/libs/1_43_0/libs/spirit/phoenix/doc/html/phoenix/i…> apply_actor is a standard MPL style metafunction "MPL-style" needs a hyphen, since the pair of words is used as an adjective. TradeStation Group, Inc. is a publicly-traded holding company (NASDAQ GS: TRAD) of three operating subsidiaries, TradeStation Securities, Inc. (Member NYSE, FINRA, SIPC and NFA), TradeStation Technologies, Inc., a trading software and subscription company, and TradeStation Europe Limited, a United Kingdom, FSA-authorized introducing brokerage firm. None of these companies provides trading or investment advice, recommendations or endorsements of any kind. The information transmitted is intended only for the person or entity to which it is addressed and may contain confidential and/or privileged material. Any review, retransmission, dissemination or other use of, or taking of any action in reliance upon, this information by persons or entities other than the intended recipient is prohibited. If you received this in error, please contact the sender and delete the material from any computer.

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Boost 1.43 - Exception before main() is called
by Rob Yull 01 Jun '10

01 Jun '10

I recently upgrade from boost 1.42 to 1.43. All of a sudden, the project I was working on seems to be throwing an exception before main() is called. I was able to reproduce this error in the example below. Using 1.42, it executes just fine. Using 1.43, an exception is thrown before main is reached. In some of my classes, I have a static mutex variable that I lock before I manipulate other static variables in the class (as seen below). main.cpp - Start #include "Test.hpp" int main() { Test test; return 0; } main.cpp - End Test.hpp - Start #ifndef DEFINE_TEST_HPP #define DEFINE_TEST_HPP #include <boost/thread.hpp> class Test { public: Test(); ~Test(); private: typedef boost::mutex StaticMutex; static StaticMutex s_Mutex; typedef boost::lock_guard<StaticMutex> StaticMutexLock; }; #endif // DEFINE_TEST_HPP Test.hpp - End Test.cpp - Start #include "Test.hpp" Test::StaticMutex Test::s_Mutex; Test::Test() { const StaticMutexLock Lock(s_Mutex); } Test::~Test() { } Test.cpp - End The code above, when using boost 1.43, produces the following error in both VC2010 Express and VC2005 Pro. First-chance exception at 0x7569b727 (KernelBase.dll) in BoostTest.exe: Microsoft C++ exception: boost::exception_detail::clone_impl<boost::exception_detail::bad_alloc_> at memory location 0x0030f6e4.. The call stack (>>> is where the exception is caught). KernelBase.dll!_RaiseException@16() + 0x58 bytes msvcr100d.dll!_CxxThrowException(void * pExceptionObject, const _s__ThrowInfo * pThrowInfo) Line 157 C++ >>>BoostTest.exe!boost::copy_exception<boost::exception_detail::bad_alloc_>( const boost::exception_detail::bad_alloc_ & e) Line 47 C++ BoostTest.exe!boost::exception_detail::get_bad_alloc<42>() Line 80 + 0x9f bytes C++ BoostTest.exe!`dynamic initializer for 'boost::exception_detail::exception_ptr_bad_alloc<42>::e''() Line 94 + 0x28 bytes C++ msvcr100d.dll!_initterm(void (void)* * pfbegin, void (void)* * pfend) Line 873 C BoostTest.exe!__tmainCRTStartup() Line 473 + 0xf bytes C BoostTest.exe!mainCRTStartup() Line 371 C kernel32.dll!@BaseThreadInitThunk@12() + 0x12 bytes ntdll.dll!___RtlUserThreadStart@8() + 0x27 bytes ntdll.dll!__RtlUserThreadStart@8() + 0x1b bytes Did something change between 1.42 and 1.43 that would cause this? -Rob Yull

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[serialization] Attaching arbitrary data to an archive
by Noah Roberts 01 Jun '10

01 Jun '10

Sometimes during serialization an object needs to know a lot more than it does during normal operation. The way I've dealt with this in the past is to subclass the archive I want to use and add setter/getters for the data that various objects down the line are going to need to store and retrieve themselves. Is there a better way though, something that's built into the library already maybe? I don't see anything but I thought I'd ask. -- http://crazyeddiecpp.blogspot.com/

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[Phoenix] documentation (if_)
by John Dlugosz 01 Jun '10

01 Jun '10

<http://www.boost.org/doc/libs/1_43_0/libs/spirit/phoenix/doc/html/phoenix/s…> Under "Lazy Statements", it gives the example of if_(arg1 > 5) cout << arg1 wondering how you managed to get operator overloading to accept that (sans brackets), I looked at the following like for 'statements'. The if_ statement does not mention this form. Should the example be: if_(arg1 > 5) [ cout << arg1 ] ? Or, if the original is expected to work, it should be mentioned at <http://www.boost.org/doc/libs/1_43_0/libs/spirit/phoenix/doc/html/phoenix/c…> along with something pointing it out more explicitly. --John TradeStation Group, Inc. is a publicly-traded holding company (NASDAQ GS: TRAD) of three operating subsidiaries, TradeStation Securities, Inc. (Member NYSE, FINRA, SIPC and NFA), TradeStation Technologies, Inc., a trading software and subscription company, and TradeStation Europe Limited, a United Kingdom, FSA-authorized introducing brokerage firm. None of these companies provides trading or investment advice, recommendations or endorsements of any kind. The information transmitted is intended only for the person or entity to which it is addressed and may contain confidential and/or privileged material. Any review, retransmission, dissemination or other use of, or taking of any action in reliance upon, this information by persons or entities other than the intended recipient is prohibited. If you received this in error, please contact the sender and delete the material from any computer.

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[Phoenix] documentation typo
by John Dlugosz 01 Jun '10

01 Jun '10

I'm not subscribed to the Spirit mailing list, but I happened to notice a typo in the documentation that I was browsing. Hopefully it will get to the attention of the right person. <http://www.boost.org/doc/libs/1_43_0/libs/spirit/phoenix/doc/html/phoenix/s…> "and it's BLL counterparts:" /it's/its/ TradeStation Group, Inc. is a publicly-traded holding company (NASDAQ GS: TRAD) of three operating subsidiaries, TradeStation Securities, Inc. (Member NYSE, FINRA, SIPC and NFA), TradeStation Technologies, Inc., a trading software and subscription company, and TradeStation Europe Limited, a United Kingdom, FSA-authorized introducing brokerage firm. None of these companies provides trading or investment advice, recommendations or endorsements of any kind. The information transmitted is intended only for the person or entity to which it is addressed and may contain confidential and/or privileged material. Any review, retransmission, dissemination or other use of, or taking of any action in reliance upon, this information by persons or entities other than the intended recipient is prohibited. If you received this in error, please contact the sender and delete the material from any computer.

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boost::variant: Wrapping C-struct inside C++ class
by Mathieu Malaterre 01 Jun '10

01 Jun '10

Hi there, Did anyone write up a small C++ wrapper class when one want to use C-struct as part of boost::variant. When using C-struct boost::variant fails with: /usr/include/boost/variant/variant.hpp:294: error: request for member ‘~__mpfr_struct [1]’ in ‘operand’, which is of non-class type ‘__mpfr_struct [1]’ make[2]: *** [CMakeFiles/variant_mpfr.dir/variant_mpfr.cxx.o] Error 1 Thanks ! -- Mathieu

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[mpl][fusion] iteration over mutiple containers
by Manfred Doudar 01 Jun '10

01 Jun '10

Hello, I've been using the Boost.PP lately, and everything now works rather nicely, but there's been a thing in the back of my head that has always been telling me, that the problem is better suited to mpl/fusion. The problem in this case is I have "two things" that need to be iterated over, one a series of tags (aka "types"), and the the other, a runtime index. I'll express what I'm after with mpl::for_each, because the issue becomes clearer that way: using namespace boost; //Func: is an object that facilitates visitation on algorithms template <template <typename> Visitor> struct Func { typedef void result_type; template <typename R, typename A> result_type operator()(A* algo) { // do work.. visit algo, with Visitor<R> apply_visitor(std::move(Visitor<R>()), *algo, ...); } } // tags are the return type on visitation typedef mpl::vector<int, float> tags; // container of algorithms Ctr<algorithms> ctr; Func<MyVisitor> ftor; mpl::for_each<tags>(bind(ref(ftor), ::_1, // [A] ctr[INDEX]))); // [B] [A]: dispatch the tag [B]: pass through algorithm instance at INDEX.. I want to do INDEX++ Of course the problem here is that I can't update INDEX in each mpl::for_each call, .. and thinking boost::fusion might be the machinery I need, but I seemingly run into other problems with that one too, there, since my tag-types are not of the same sequence as my container of algorithms. What I want is to pass in the appropriate tag, for each instance of algorithm from a container. Indeed, for those wondering, I have tried a typedef on each algorithm, ..was hoping I could access the nested type A::type in place of R in Func above, however, owing to the visitation mechanism, doing so gives problems of access to incomplete-types elsewhere in the chain. If anyone can suggest something, I'd be happy to hear it, ...as I said, what I have already works, but I have a hard time letting this one rest, knowing that there is a better alternative, but am not quite seeing it yet. Cheers, -- Manfred

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[Random] random_device and windows - multiply defined symbols
by Tore Halvorsen 01 Jun '10

01 Jun '10

The release notes for Boost 1.43 says "Put the implementation of random_device in a compiled lib, and added Windows support." Trying to use this library does not seem to work for me, under visual studio 2005, with static libraries. #include <cstdlib> #include <boost/nondet_random.hpp> int main(int argc, char* argv[]) { boost::random_device d; return EXIT_SUCCESS; } 1>libboost_random-vc80-mt-sgd-1_43.lib(random_device.obj) : error LNK2005: "public: static bool const boost::random_device::has_fixed_range" (?has_fixed_range@random_device@boost@@2_NB) already defined in main.obj 1>libboost_random-vc80-mt-sgd-1_43.lib(random_device.obj) : error LNK2005: "public: static unsigned int const boost::random_device::min_value" (?min_value@random_device@boost@@2IB) already defined in main.obj 1>libboost_random-vc80-mt-sgd-1_43.lib(random_device.obj) : error LNK2005: "public: static unsigned int const boost::random_device::max_value" (?max_value@random_device@boost@@2IB) already defined in main.obj 1>Debug\Win32\random_device.exe : fatal error LNK1169: one or more multiply defined symbols found -- Eld på åren og sol på eng gjer mannen fegen og fjåg. [Jøtul] <demo> 2010 Tore Halvorsen || +052 0553034554

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[preprocessor] add pointer to T..
by Manfred Doudar 01 Jun '10

01 Jun '10

Hello, Thinking maybe little to late in the night at my end, but can see how to generate the following: T0* T0*, T1* T0*, T1*, T2* ..and so on Some variant on the below maybe..? Of course, below, you'd get T*0, T*1, etc if tried BOOST_PP_ENUM_PARAMS(n, T*) which doesn't produce a valid token. #include <boost/preprocessor/iteration/local/hpp> #include <boost/preprocessor/repetition.hpp> #define OPERATOR(z, n, _) \ \ BOOST_PP_ENUM_PARAMS(n, T) /**/ #define BOOST_PP_LOCAL_MACRO(n) OPERATOR(_, n, _) #define BOOST_PP_LOCAL_LIMITS(1, 3) #include BOOST_PP_LOCAL_ITERATE() #undef BOOST_PP_LOCAL_MACRO #undef BOOST_PP_LOCAL_LIMITS #undef OPERATOR All help appreciated. Cheers, -- Manfred

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BGL property maps
by Arne Schwabe 01 Jun '10

01 Jun '10

Hi, I trying to wrap my head about the usage of iterator_property_map<RandomAccessIterator, OffsetMap, T, R> What I am trying to do is the following: create a map like color with key a graph_node and value type of a struct like struct foo { int numbervists; int color; } so I can use that in a breadth first like algorithm. The example shows me how to do it for an int but do not know how to change typedef boost::graph_traits<Graph>::edge_descriptor Edge; typedef boost::property_map<Graph, boost::id_tag>::type EdgeID_PMap; EdgeID_PMap edge_id = get(boost::edge_index(), G); boost::iterator_property_map<int*, EdgeID_PMap, int, int&> capacity_pa(capacity, edge_id), flow_pa(flow, edge_id); to use foo instead of int. In my understanding, I would have to change int* to a RandomAccessIterator to to Iterator that has foo as value type. But I am kind of lost how to construct such a thing. Arne

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