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Re: [Boost-users] Boost Logos: proposed high constrast logo
by Zoltan Juhasz 08 Oct '10

08 Oct '10

Follow up on the original topic: I've uploaded a high-contrast version of the Boost Logo, and moved all other logo related resources to the follow Google Docs folder: https://docs.google.com/leaf?id=0B_WA6oW88X1UZWZiNzUwYzctYzg1NS00ZmY5LTllMD… On the logo discussion: Various explanation could be made for the logo. For some these are molecular structures; for others this is a small matrix of hexagonal cells from a beehive; some may claim these are interconnected - in some places overlapping - software components etc. Probably all of these seem reasonable, maybe non of these for someone. My point is that one could come up with any justification for the hexagons, but it will not change others mindset on it. On the other hand... ... this is an abstract logo, which is fairly simple (well at least the stylized form), it does not bring any cultural or any specific technology connotations, and most importantly provides / provided a "face" for Boost in the last 4 (or 5?) years. This is a strong connection in public mind between the Boost community and the logo; where the previous one defines the later - which (the community, and the Boost project) has excellent reputation, which made the logo highly recognizable (like any famous company brand). The point is, it is not the logo which defines Boost, but the other way around. Ofc. if the logo was something like this: http://preview.tinyurl.com/2wcg757 that would be arguably a big deflection compared to the spirit of Boost, but I do not think this applies to the current case (chemical analogy). The other important point is that most of the developers that used Boost in the previous years, already made the connection between the logo and the Boost Libraries; making a radical change might be a bad idea, unless there is a really strong reason to do that (for example Boost ceases using C++, and focusing on Objective C from now), otherwise keeping the continuity is important. I hope the high contrast version of the logo is usable, let me know if you need further help with it. I also hope that I was able to give you some background on the abstract hexagons. Regards, Zoltan Juhasz

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[proto] baby steps learning with proto, proxy object
by alfC 08 Oct '10

08 Oct '10

Hi, This can be an exercise for definining the scope of Boost.Proto for little things. I have a histogram class that internally looks like this class histogram{ ... bool operator()(double const& x){return impl.increment(x);} bool operator()(double const& x, double const& weight){return impl.accumulate(x, weight);} }; histogram h( .. bin spec .. ); double x = ... ; so to add a count to the bin of x, I call h(x); to add a count with weigh w to bin x, I call h(x,w); so far so good. Now suppose I want to "improve" the syntax. The desired syntax would be: h[x]++; h[x]+=w; I don't want to expose the internal representation of the bins, so I can't return a reference to something from h[x]. So I guess we can create a proxy of the expression h[x] , "subindex of historgram with double". The proxy can be used with the syntax to call either accumulate or increment depending on the application of += or + + to the proxy. The naive implementation is this: class histogram{ ... private: struct proxy_histogram_subscript{ histogram& self; double const& x; proxy_histogram_subscript(histogram& self, double const& x) : self(self), x(x){} proxy_histogram_subscript const& operator++() const{self.increment(x); return *this;} bool operator++(int) const{return self.increment(x);} bool operator+=(double const& weight) const{return self.accumulate(x, weight);} }; public: proxy_histogram_subscript operator[](double const& x){ return proxy_histogram_subscript(*this, x); } }; which allows the desired syntax. The question is, can Boost.Proto do better? What I don't understand is how proto can make such a mini language *inside* the class. Hopefully without adding to much lines of code. I can see that one could create a histogram terminal, but that will be public (e.g. from the main program) and that will allow to create all sorts of expression involving brackets of anything. Thank you, Alfredo

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How to abort boost test execution on the failure of any BOOST_TEST_CASE
by Gaurav N Shah 08 Oct '10

08 Oct '10

Hi, I have sample code like this: void test1() { BOOST_REQUIRE(2 ==1); } void test2() { BOOST_CHECK(1 !=1); } boost::unit_test::test_suite* ts1 = BOOST_TEST_SUITE( "test_suite1" ); ts1->add(BOOST_TEST_CASE(&test1)); ts1->add(BOOST_TEST_CASE(&test2)); ::boost::framework::master_test_suite().add(ts1); In this case I do not want test2 function to be executed it test1 fails. How is it possible?? (I can not merge code in test1 and test2 into single function) Thank You, Gaurav This communication is for informational purposes only. It is not intended as an offer or solicitation for the purchase or sale of any financial instrument or as an official confirmation of any transaction. All market prices, data and other information are not warranted as to completeness or accuracy and are subject to change without notice. Any comments or statements made herein do not necessarily reflect those of JPMorgan Chase & Co., its subsidiaries and affiliates. This transmission may contain information that is privileged, confidential, legally privileged, and/or exempt from disclosure under applicable law. If you are not the intended recipient, you are hereby notified that any disclosure, copying, distribution, or use of the information contained herein (including any reliance thereon) is STRICTLY PROHIBITED. Although this transmission and any attachments are believed to be free of any virus or other defect that might affect any computer system into which it is received and opened, it is the responsibility of the recipient to ensure that it is virus free and no responsibility is accepted by JPMorgan Chase & Co., its subsidiaries and affiliates, as applicable, for any loss or damage arising in any way from its use. If you received this transmission in error, please immediately contact the sender and destroy the material in its entirety, whether in electronic or hard copy format. Thank you. Please refer to http://www.jpmorgan.com/pages/disclosures for disclosures relating to European legal entities.

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Program Options.. Specifying "-e" as an option value.....
by david.weber＠l-3com.com 08 Oct '10

08 Oct '10

I have an application, which spawns off other applications. As input, it takes in environment variables and arguments to pass to the resultant application. For instance: mutate -E "env_var1=val" -a "." ls This will run: ls . and the environment will only have "env_var1" equal to "val" So. Something funny comes along when I try to pass "-e" as an argument. So, in the above would be: mutate -a "-e" -a "foo" xterm The program options parser attempts to parse the "-e", and says "I don't know what it is". Any thoughts on having it skip that option? Code Snippits: po::options_description visible("Program options. Usage %1%"); visible.add_options() ("env,E", po::value<string_vector_t>(), "Specify an environment variable to run the executable with. In the form of foo=bar") ("arg,a", po::value<string_vector_t>(), "Specify a command line argument to pass to the executable") ; // Set up some hidden options po::options_description hidden("Hidden options"); hidden.add_options() ("executable", po::value < std::string>(), "the executable to run") ; // Set up positional arguments. They are going to be execute po::positional_options_description pos; pos.add("executable", 1); // There can only be 1 item executed // Consolidate all the options into a single one po::options_description all_options("All Options"); all_options.add(visible); all_options.add(hidden); // Parse the command line options po::store(po::command_line_parser(argc, argv).options(all_options).positional(pos).run(), vm); po::notify(vm);

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[Boost.Log] How to link with on MSVC 2008?
by RUOFF, LARS (LARS)** CTR ** 08 Oct '10

08 Oct '10

Hello, i have found the following instructions to build Boost.Log: > Boost.Log can be compiled by: > > 1. Getting 1.42 source release > 2. Unpacking Boost.Log on top of it > 3. Following the usual procedure: > > .\bootstap.bat > .\bjam --with-log I did the above starting from a 1.44 source release. This worked out well. But when trying to use the library I get a lot of linker errors in my project: 1>Linking... 1>libboost_log-vc90-mt-gd-1_44.lib(text_file_backend.obj) : error LNK2019: unresolved external symbol "class boost::filesystem2::file_status [...] (Very long error messages containing decorated names. The above is just the start) Linker path settings should be correct, since the linker correctly finds libboost_log-vc90-mt-gd-1_44.lib. Also the project is using other Boost libraries (Asio, shared-ptr, bind, posix-time, etc) without problems. Anyone managed to compile and use Boost.Log on MSVC 2008 and can help? Thank you, Lars Ruoff

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[Math] Best Way to Produce Pi
by Hossein Haeri 08 Oct '10

08 Oct '10

Dear all, What's my best way to define a constant for Pi. I'm thinking of using the following <cmath> stuff: const double pi(4 * atan(1)); Does Boost provide a better solution? TIA, --Hossein

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[boost-users] [bind][function] - too many copies
by Lorimer, Stephen 08 Oct '10

08 Oct '10

For a given member function of the form void foo::f0(), passing this to boost bind results in the class instance being copied 7 times. Storing the result of bind in boost function incurs another 11 copies (code and results are here: http://boost.codepad.org/6jBmoKuj) Using tr1::bind and function has slightly better results, but still not ideal: Doing just tr1::bind results in the class instance being copied 4 times. Storing the result of bind in tr1 function incurs another 3 copies (code and results are here: http://boost.codepad.org/w1EV6JBY) Am I right in saying this is because boost::bind uses normal templates while tr1::bind uses variadic templates? Either way this is not very efficient. Is there a way to improve this? ---------------------------------------------------------------------- This message w/attachments (message) is intended solely for the use of the intended recipient(s) and may contain information that is privileged, confidential or proprietary. If you are not an intended recipient, please notify the sender, and then please delete and destroy all copies and attachments, and be advised that any review or dissemination of, or the taking of any action in reliance on, the information contained in or attached to this message is prohibited. Unless specifically indicated, this message is not an offer to sell or a solicitation of any investment products or other financial product or service, an official confirmation of any transaction, or an official statement of Sender. Subject to applicable law, Sender may intercept, monitor, review and retain e-communications (EC) traveling through its networks/systems and may produce any such EC to regulators, law enforcement, in litigation and as required by law. The laws of the country of each sender/recipient may impact the handling of EC, and EC may be archived, supervised and produced in countries other than the country in which you are located. This message cannot be guaranteed to be secure or free of errors or viruses. References to "Sender" are references to any subsidiary of Bank of America Corporation. Securities and Insurance Products: * Are Not FDIC Insured * Are Not Bank Guaranteed * May Lose Value * Are Not a Bank Deposit * Are Not a Condition to Any Banking Service or Activity * Are Not Insured by Any Federal Government Agency. Attachments that are part of this EC may have additional important disclosures and disclaimers, which you should read. This message is subject to terms available at the following link: http://www.bankofamerica.com/emaildisclaimer. By messaging with Sender you consent to the foregoing.

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Boost Logos: proposed high constrast logo
by Alfredo Correa 08 Oct '10

08 Oct '10

Hi all, In my opinion there should be a high contrast version of the Boost logo . (by that I mean either black and white or high contrast with very mild gradients on white background). Particularly I am talking about the three hexagons icon. As an example, the first attachment here has the official logo in SVG format. Because of the background gradient and the gradient fill of the hexagon it is not *obvious* how to convert this to high contrast. What should be replaced by black (or solid blue)? the hexagon filling? the hexagon borders? the background? A possible high contrast logo is attached in the second file. By no means official or the best option, it is just an possibility, maybe the simplest one. *Just an example*. Note that even the darkest blue used in the gradient of the official logo is not enough to contrast with white, so I used a darker blue. The reason I think a high contrast logo is the following: If you want to have a document printing quality (or high quality PDF) you need a vector format. If the printing or visualization is done in black and white, the logo should have high contrast otherwise the appearance will be very device dependent. While everyone should take care in printing in good devices having a logo that is barely visible in black/white/grey printing in some devices is not acceptable. As a test for what makes a high contrast logo a good one, just try printing and small version (one centimeter square) of the logo in a black and white laser printer with random text around it and you will see the problem with the low contrast original logo. It will appear like a grey blob at best. Please this thread is not about a new logo design just an adaptation of the existing one. This thread is not be related with the "Powered by" logo discussion Alfredo PS: the attachments are Inkscape SVG.

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[statechart] Unhandled events
by Oleg Smolsky 07 Oct '10

07 Oct '10

Hey there, I've been using SC for a while and something has been bugging me - given a state machine with: OuterSt, OneSt and TwoSt as well as OneEv and TwoEv that are handled by OneSt and TwoSt respectively, it is possible to send a wrong event to either of the last two states. Such an "unhandled" event will be forwarded to OuterSt and then quietly eaten. My question is as follows - is it possible to define some kind of "catch all" handler in the OuterSt? I have already fixed a tricky bug in my code where a submitted event was lost, and wonder if there is a simple way to handle these situations? I can certainly add a custom_reaction<>(X) for each possible event to the OuterSt and catch issues that way, but that's far from ideal. Any suggestions would be appreciated. P.S. perhaps a compromise solution would be to add something like this to OuterSt: sc::bug<OneEv> sc::bug<TwoEv> but that would effectively limit handling to issuing an assert(false)... Thanks, Oleg.

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[boost-spirit qi] internal copies
by Ovanes Markarian 07 Oct '10

07 Oct '10

Hello *, I think this is more the question to spirit devlopers. I would like to know how spirit internally maintains the parsed data? Here is an example of what I mean. I have to parse some byte sequence represented as hex pairs: 00 ce ab 00 de ad be ef ... If I use the parser like this: boost::spirit::qi::uint_parser<unsigned char, 16, 2,2> hex_byte; std::string str("..."); std::vector<byte_t> vec; iter_type curr=str.begin(), end=str.end(); bool r=phrase_parse(curr, end, +hex_byte, space, vec); Is vec going to be copied somewhere inside of qi? Or are the bytes directly appended to the vec? I would like to reserver some space for the maximum possible input and avoid additional internal copies inside of qi... How does the behaviour changes std::vector<byte_t> is part of the fusion::map like fusion::map < fusion::pair<tag1, string> , fusion::pair<tag2, string> ... , fusion::pair<tagN, std::vector<byte_t> > > data_item; Are the fields of the map used directly while parsing, or are there some temporaries, which will be first created (somewhere inside qi core) and filled with data and afterwards assigned to the corresponding map field? Many thanks for the gread lib! Ovanes

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