February 2014 - Boost - lists.boost.org

[Fibers] Performance
by Hartmut Kaiser 10 Feb '14

10 Feb '14

Oliver, Do you have some performance data for your fiber implementation? What is the (amortized) overhead introduced for one fiber (i.e. the average time required to create, schedule, execute, and delete one fiber which runs an empty function, when executing a larger number of those, perhaps 500.000 fibers)? It would be interesting to see this number when giving 1..N cores to the scheduler. Thanks! Regards Hartmut --------------- http://boost-spirit.com http://stellar.cct.lsu.edu

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GSoC 2014 - Full Text Search
by Nikhar Agrawal 09 Feb '14

09 Feb '14

Hi everyone, I'm Nikhar Agrawal, currently pursuing my B.Tech. in Computer Science and Engineering from IIIT-H. I was a GSoC student last time for Boost C++ under the mentorship of Christopher Kormanyos and advisory mentorship of John Maddock and Paul Bristow for the Boost.Math Bernoulli numbers project. It was a wonderful experience to have successfully managed to contribute to Boost. And it was a great learning process. I would love to participate this year as well. I was going through the ideas page and saw 'Full Text Search' listed in tiny letters near the bottom of the page. As part of our coursework on Information Retrieval and Extraction in college, we have built a project on searching for queries on a 42 gb wikipedia xml dump. So, I got a little excited at seeing 'Full Text Search' being listed. I skimmed through the Boost mailing list archives but couldn't find any information on this. Could someone kindly elaborate what exactly is expected from this? And if there's any interest from anyone in mentoring this project? Thanks.

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GSoC
by Utsav Tiwary 09 Feb '14

09 Feb '14

Are there existing libraries for the implementation of finite difference method to solve boundary value problems ? I've been working on it lately using MPI.

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[Move] BOOST_NO_RVALUE_REFERENCES - or so it thinks
by John M. Dlugosz 08 Feb '14

08 Feb '14

Real-world software projects don't always get to use the latest stuff in a timely manner. I'm working on some code that needs to work across several platforms, which generally means programming to the least-common-denominator. What I want to bring up in particular is the issue that the compiler may be more up to date with C++11 than the libraries. Someone trying to use Boost on Android (IIRC) trying to change the Boost config to tell it that C++11 support is available said it was like playing "Whack-a-Mole", in that each change caused more problems elsewhere. It seems that the overall issue is Compiler vs Library. Saying that rvalue references are available doesn't mean that std::move, std::forward, etc. are available. I threw together a move.h file that contains forward, move, and a few others taken exactly from the standard â all one-liners. That lets people who know that the compiler really does know what to do with && write code that uses them, just so long as they remember to use the project's namespace and not std, or the multi-platform build coughs it back out. I also successfully crossbred the unique_ptr implementation from libcxx-3.4 with Boost + my own move.h namespace. Now try putting a (real) move-only object into a boost::container::vector when Boost is built with BOOST_NO_RVALUE_REFERENCES. Might I convince the powers-that-be to reconfigure Boost with that #define removed? That could be done when upgrading Boost anyway, but it seems to not work! Whack-a-mole. I didn't do it personally, but it appears that at the very least Boost would need its own move.h and whatever odds and ends it assumes are present. That would be quite easy since these little functions are just fancy casts and you can mix code that calls different "implementations" of them. So Boost could always use boost::move which turns into static_cast<typename boost::remove_reference<T>::type&&>(t); (as opposed to just 'using' the std::move) and other code doesn't care. That is, it would not be necessary to configure "has std::move vs not have std::move" but just don't rely on std::move at all. In short, I don't know if it's just me, but most of the company jobs I've worked have lagged behind, with upgrading the compiler and/or libs being a Big Deal, especially if using outside code that's already compiled. So, I want to raise the possibility that making Boost work with native rvalue references but legacy (C++03) standard library would be useful to some significant population of developers. #undef'ing BOOST_NO_RVALUE_REFERENCES in the config ought to just work, at least on a lib by lib basis. I mean, it might be fine if some libs didn't handle that as many people don't use every single lib in every project. Boost.Container is interesting though because it is used to overcome legacy std::map etc. as one of its stated goals. It's also good for avoiding platform compatibility issues when all platforms use the same map class (e.g. the master build doesn't spit out failures as erase is void on some platform but returned an iterator on the platform used to try the code before checking it in). The current version of Clang as used for Mac and iPhone/iPad development has && working even if you don't enable the C++11 dialect. So sneaking in some &&'s in a program doesn't require any reconfiguration of the projects. âJohn

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Fwd: [Boost-users] Attn: We need GSoC 2014 mentors for Boost!
by Antony Polukhin 08 Feb '14

08 Feb '14

2014-02-08 7:15 GMT+04:00 Niall Douglas <s_sourceforge(a)nedprod.com>: <...> Therefore, if you think yourself able to mentor a student doing some > work on Boost this summer, *please* consider adding a description of > the proposed work item and your name to the list at > https://svn.boost.org/trac/boost/wiki/SoC2014. > I'm in! How about the following projects: * Running regression tests on Android/RaspberyRI/Qemu, writing a documentation about crosscompiing Boost libraries. + Adding automated TravicCI testing scripts to all the Boost libraries * Library for basic integration with spreadsheet applications Excel/LibreOfficeCalc/OpenOfficeCalc and OfficePrograms (Modifying cell, getting results from cells, saving documents, saving in PDF) * Program protection and obfuscation tools (marking part of assembly at compilation, encrypting/decrypting part of the binary on-the-fly, detecting debuggers, detecting emulators and virtual machines, computer identification and gathering hardware specific identifiers...) If there is an interest in those projects, I'll add some description to the GSOC wiki page. -- Best regards, Antony Polukhin

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Odd regression test results
by Peter Dimov 08 Feb '14

08 Feb '14

Something's not right with this result (among others): http://www.boost.org/development/tests/develop/developer/output/teeks99-02e… It says "Rev 906385497d1f3de04bb8391c5af87e563fd4c0f7". Revision 906385 updates config, and the preceding revision that updates smart_ptr is https://github.com/boostorg/boost/commit/891371e4ba8edf7dd21dc828841f5eab56… which brings it up to +Subproject commit e1f170cd494d2e7ce5e6e7d3f0fe016aceb88048 Rev. e1f170 of smart_ptr is a relatively recent one, as can be seen here: https://github.com/boostorg/smart_ptr/commits/develop The error messages in the report, however: C:\local\teeks99-02\e\boost_root\boost/smart_ptr/detail/shared_count.hpp(276) : error C2903: 'rebind' : symbol is neither a class template nor a function template C:\local\teeks99-02\e\boost_root\boost/smart_ptr/make_shared_object.hpp(174) : see reference to function template instantiation 'boost::shared_ptr<int>::shared_ptr<T, ... seem to suggest that neither shared_count.hpp nor make_shared_object.hpp have been updated to e1f170.

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Cairo and ISO C++ for GSoC proposed?
by Mateusz Łoskot 08 Feb '14

08 Feb '14

Hi, I haven't been monitoring the GSoC discussions closely, just looked at the final https://svn.boost.org/trac/boost/wiki/SoC2014 I'm wondering, has anyone proposed for GSoC to kickstart initial work on Cairo for ISO C++ according to the papers posted by Herb Sutter? Here is Herb's post: http://lists.cairographics.org/archives/cairo/2013-December/024858.html Best regards, -- Mateusz Łoskot, http://mateusz.loskot.net

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[testing] More failed test results with no meaningful content
by John Maddock 08 Feb '14

08 Feb '14

For example: http://www.boost.org/development/tests/develop/developer/output/marshall-ma… leads to a successfully compiled file if you follow the links. Anyone any idea what's going on here, and is there any way to make this reporting more reliable? Frankly the results will get widely ignored if no one can see what's actually going on. Thanks, John.

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Gsoc chrono::date Library
by Arun Sori 08 Feb '14

08 Feb '14

Hey All, I am interested in contributing to the chrono::date library project.I have read the paper given in the link and need some ideas on how to start. I am a new contributor so please guide me to the initial phase and spare no details. As a start the paper seems to propose a new library based on boost::date. Should I first familiarize with the boost::date code ( try to compile it. Read the documentations etc.). The project also has a prototype available. Are we trying to build the library further upon it ? What extra do we need to built in this project ? What are some mandatory prerequisites for the project ? Thanks, Arun

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[boost-bugs] Where is the archive, please?
by Fletcher, John P 08 Feb '14

08 Feb '14

I am maintaining Boost phoenix and whenever I put comments onto the bug trac I get an email with a copy from boost-bugs. I would like to look at the archive of this but it is not listed on the gmane lists. http://news.gmane.org/index.php?prefix=gmane.comp.lib.boost It must be somewhere else. Please help. John Fletcher

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[testing] Strange Darwin test failures
by John Maddock 08 Feb '14

08 Feb '14

Does anyone know why this would happen: http://www.boost.org/development/tests/develop/developer/output/marshall-ma… program exits with: libc++abi.dylib: terminate called throwing an exception Googling around finds: http://apple.stackexchange.com/questions/103649/macports-dylib-failure-with… which suggests some sort of toolset misconfiguration? Thanks, John.

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Phoenix 3.0.4 on master. Fixes include silent bugs.
by Fletcher, John P 07 Feb '14

07 Feb '14

Phoenix 3.0.4 is now on master and will I hope be included in the next release of Boost. There are many fixes to bugs which are documented in libs/phoenix/ChangeLog In particular there are fixes for #5715 and #5824. These are important as they were silent bugs which meant that code did not work correctly. This means that it is possible that there is code using phoenix where the results could change when adopting this release. There are many fixes still to be done which are documented in the TODO section of the changelog. Please report any concerns or bugs either through trac or by responding to this message. John Fletcher

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[modular-boost] /boost//headers error
by Thomas Suckow 07 Feb '14

07 Feb '14

I am seeing a strange discrepancy between building the headers target from the command line vs including it as a dependency in another target. In our own projects we 'use-project /boost : $(PATH_TO_BOOST) ;' and use the headers target. But as a reproducible example, if I add /boost//headers to tools/quickbook/src/Jamfile.v2 I get: http://pastebin.com/KMcMSLZW I tried to debug it, but alas my skills at boost-build seem to be insufficient. It is interesting to note however that when looking at 'b2 -d5' output 'sequence.join library-name-headers .' seems to be invoked when it fails, yet that does not occur when it succeeds. If anyone has any ideas on how to get this working again, I would be happy to look into this more. -- Thomas I for one welcome our new git overlords.

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GSoC Hypergeometric functions (Pratyaksh Sharma)
by Pratyaksh Sharma 07 Feb '14

07 Feb '14

Hello I'm interested in the Boost.Math Generalized Hyper geometric Functions project. Can anyone give some pointers on where to begin? I have sufficient experience with hypergeometric functions, but don't know exactly how to contribute to Boost. Just to start the discussion: Does everyone agree that a variety of methods need to employed for calculating the functions for different ranges of parameters? I'm familiar with methods that utilize the Gauss-Jacobi quadrature to solve the differential equation of concern, and also the Taylor series methods for smaller values of |a| and |z|. Any other ideas? Cheers, Pratyaksh

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Regression tests for 'develop'
by Edward Diener 06 Feb '14

06 Feb '14

Are the regression tests for 'develop' for any particular library running the 'develop' branch of that library against the 'master' branch of all other libraries ? Or is the regression test for 'develop' for any particular library running against the 'develop' branch of all other libraries ?

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sqlpp11: SQL for C++
by Roland Bock 06 Feb '14

06 Feb '14

Hi, over the last four or five years I developed several SQL libraries for C++. With C++11 I was finally able to create an SQL library that meets my own expectations and requirements. It is being used in production, I recently put it on github, and I would really like to hear from you guys whether this is something that could be interesting for you personally or for boost? https://github.com/rbock/sqlpp11 https://github.com/rbock/sqlpp11/wiki sqlpp11 is a template library representing an embedded domain specific language (EDSL) that allows you to * define types representing tables and columns, * construct type safe queries checked at compile time for syntax errors, type errors, name errors and even some semantic errors, * interpret results by iterating over query-specific structs with appropriately named and typed members. This results in several benefits, e.g. * the library user operates comfortably on structs and functions, * the compiler reports many kinds of errors long before the code enters unit testing or production, * the library hides the gory details of string construction for queries and interpreting string based results returned by select calls. I.e. you don't need to use strings in query construction where you wouldn't use them in SQL and there is no need to use positional arguments or to parse strings when obtaining fields from a result row (the latter being true unless you do not know which columns to select at compile time). The library supports both static and dynamic queries. The former offers greater benefit in terms of type and consistency checking. The latter makes it easier to construct queries on the flight. Specific traits of databases (e.g. unsupported or non-standard features) are known at compile time as well. This way, the compiler can tell the developer at compile time if a query is not accepted by the database (e.g. if a feature is missing). And the library can form the query in the correct manner, for instance if the engine uses concat instead of operator|| to concatenate strings. Two Examples: ============= Static Select: -------------- // selecting zero or more results, iterating over the results for (const auto& row : db.run( select(foo.name, foo.hasFun) .from(foo) .where(foo.id > 17 and foo.name.like("%bar%")))) { if (row.name.is_null()) std::cerr << "name will convert to empty string" << std::endl; std::string name = row.name; // text fields are implicitly convertible to string bool hasFun = hasFun; // bool fields are implicitly convertible to bool } Dynamic Select: ---------------- auto s = dynamic_select(db, tab.foo).dynamic_columns().from(tab); if (userWantsBar) s.add_column(tab.bar); for(const auto& row : run(s)) { std::cerr << "row.foo: " << row.foo; if (userWantsBar) std::cerr << "row.bar" << row.at("bar"); std::cerr << std::endl; }; Please let me know your questions/thoughts/suggestions/rants. Contributions welcome, of course :-) Regards, Roland

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[config] BOOST_NO_CXX11_ALLOCATOR and template aliases
by Peter Dimov 06 Feb '14

06 Feb '14

VC11 appears to not define BOOST_NO_CXX11_ALLOCATOR. However, as std::allocator_traits contains two template aliases, rebind_alloc and rebind_traits, and VC11 doesn't support template aliases, it has nonstandard definitions of these two. This is obviously a problem for code that wants to use std::allocator_traits. One way to fix that is for the user code to check BOOST_NO_CXX11_TEMPLATE_ALIASES and if so, refrain from using std::allocator_traits. Another is to just not define BOOST_NO_CXX11_ALLOCATOR for VC11. (VC12 is conforming.) I tend to be in favor of the second option, as the effect would essentially be the same.

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What is trac doing and how do I stop it doing it??
by Fletcher, John P 06 Feb '14

06 Feb '14

I am attempting to update a ticket and I am getting this: ------------------ Captcha Error Submission rejected as potential spam (Content contained 1 blacklisted patterns) Trac thinks your submission might be Spam. To prove otherwise please provide a response to the following. ------------------- I would not mind but there is nothing to respond to and what I have typed seems to be lost. Where is there guidance on how to avoid this problem, please? John

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Re: [boost] SQL: next iteration of sqlpp11
by Sebastian Theophil 06 Feb '14

06 Feb '14

> On 2014-02-03 16:03, Roland Bock wrote: > In most usecases I encountered so far, it is totally OK to interpret NULL > values like default values, e.g. NULL strings and empty strings, or NULL > foreign keys or 0LL. For those usecases it would be quite annoying to have to > check if there really is a value, or always use get_optional_value_or... Hi Roland, while I can very well imagine that these "use-cases" exist, I would not like the library to make this the default. I think using boost::optional is the canonical solution that is also impossible to misinterpret. Treating non-existent values the same as default-initialized values seems error-prone if not wrong in general. The library should not prevent me from treating string "" differently from NULL, which currently it does. On the other hand, if the library did return optionals, implementing the behaviour you describe on top of it is trivial: boost::optional<T> t; t.get_value_or( T() ); If it helps my argument, both Scala Anorm and Scala Slick represent nullable columns as optional types: http://www.playframework.com/documentation/2.0/ScalaAnorm http://slick.typesafe.com/doc/2.0.0/schemas.html Regards Sebastian PS: I hope to look at your library in more detail in the coming weeks and I am really looking forward to that. Great work so far. -- Dr. Sebastian Theophil | stheophil(a)think-cell.com Senior Software Engineer think-cell Sales GmbH & Co. KG | Chausseestr. 8/E | 10115 Berlin | Germany http://www.think-cell.com | phone +49 30 666473-10 | US phone +1 800 891 8091 Amtsgericht Berlin-Charlottenburg, HRA 44531 | European Union VAT Id DE815233792 General partner: think-cell Operations GmbH | Amtsgericht Berlin-Charlottenburg HRB 129917 Directors: Dr. Markus Hannebauer, Dr. Arno Sch?dl

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Large Bitset to download?
by Aleksey Yakovlev 05 Feb '14

05 Feb '14

Dear List, This is my first post to the list. I’ve subscribed to get some info about Zachary Turner project “Large Bitset” (based on Joachim Faulhaber ICL). What’s the status of this project? It looks promising for us, so I’d like to download sources and take a dig into them – to test, to estimate limits, performance etc. Please help, Thanks, Aleksey This message contains confidential information. If you are not the intended recipient you are hereby notified that disclosing,copying, distributing or taking any action in reliance on the contents of this information is strictly prohibited. Please notify the sender immediately and delete this e-mail from your system.

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GSoC: Who is taking on the responsibility as organization admin for Boost this year?
by Hartmut Kaiser 04 Feb '14

04 Feb '14

Sorry if I missed this information... Regards Hartmut --------------- http://boost-spirit.com http://stellar.cct.lsu.edu

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[modular-boost] Questions about development procedures and more
by Gennadiy Rozental 04 Feb '14

04 Feb '14

Hi, Trying to start using modular boost (and git for that matter). I have several questions about this. These are in no particular order: 1. Why does ./b2 headers on windows creates hardlink for each file instead of directories? The process takes forever. 2. What the story about cmake based build? What state is it in? Can I try it now? How? Can I help with anything to push this further? I got a bit of experience with cmake since last time I see n this discussed. 5. What the status of testing of the new tree? How is it setup? Where can I read it? Specifically I am interested in what being tested against what. 4. First command to switch to develop branch produces warning(?) ...\modular-boost\libs\test>git checkout develop Previous HEAD position was 954d3ab... Thread: merge [81791]-tools dir missing Branch develop set up to track remote branch develop from origin. Switched to a new branch 'develop' Should I worry? 5. After I switched to development branch headers directory still "points to" master branch files. Actually I am not sure what it points to now since master files are nowhere anymore. How should I switch headers? 6. What the corresponding action with git, which does what svn up from root of tree did before? What I am after is comamnd(s) which updates other libs, but keep my lib as is (maybe merge changes from other developers). If "git submodule update" is one of these commands, why does it takes forever on fresh just cloned boost tree? 7. How do I run the test which will check how my changes affect other libraries (their master branch at least). Should I just run the test from root in my local copy? How do I test against develop branch of other libs and develop branch of other libs against me? 8. Dependency specification. This actually a big question, which can be split into several: 8.1 Is there place where I can see "released versions" for particular library/submodule? 8.2. Is there way to tell which other boost submodules I depend on? 8.3 Can I specify specific release version I want to depend on (per submodule)? 8.4 Can I somehow only checkout/pull the submodules I depend on? 8.5 Can I check which submodules depend on me and checkout only those? 8.6 Is there place where I can see which submodule version constitute specific boost release? 9. One of the wiki pages refers to "git submodule summary" command. I do not understand what this command supposed to do. 10. How do I create private branch? IOW branch which is not publicized on github, but one I can share with the team? 11. This page is not clear to me: https://svn.boost.org/trac/boost/wiki/PostCvtMergePoint What do I need to do to merge my development branch into master, given that it is significantly differ now (at the time of svn->git conversion)? Thank you. Gennadiy

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SQL: next iteration of sqlpp11
by Roland Bock 04 Feb '14

04 Feb '14

Dear boosters, after the lively discussion about sqlpp11 in November 2013 (http://lists.boost.org/Archives/boost/2013/11/208388.php) sqlpp11 has evolved quite a bit and I want to give you an update. https://github.com/rbock/sqlpp11 *) sqlpp11 now supports prepared statements. For instance auto ps = db.prepare(select(all_of(tab)) .from(tab) .where(tab.alpha != parameter(tab.alpha))); ps.params.alpha = 42; for (const auto& row: db.run(ps)) { std::cerr << "alpha: " << row.alpha << std::endl; std::cerr << "beta: " << row.beta << std::endl; std::cerr << "gamma: " << row.gamma << std::endl; } *) Binding of parameters and results for binary transport is now supported. Both, parameters of prepared statements and results can be bound to in-memory data of the database now. In the example above, using the provided mysql connector, neither parameters nor the non-text results are converted to/from string. *) Support for multi-row insert: //First, you create an insert: auto i = insert_into(tab).columns(tab.alpha, tab.beta); //Then you add values (one or more times): i.values(tab.alpha = 7, tab.beta = "seven"); // Then you run the insert db.run(i); There is no support for array binding in sqlpp11, since this is highly vendor specific afaict. But it would be fairly easy to add support for this in the vendor-specific connector library. I'd be happy to support you if you wanted to give it a try. *) New interpreter for SQL expression trees: This has changed and improved a lot. sqlpp11 has been stripped of all vendor specific code and will serialize standard SQL. The connector libraries can specialize an interpreter template to change the representation of certain aspects. For instance, mysql would represent the concatenation of strings as CONCAT(a,b) instead of a||b. But of course, the connector libraries are not required to turn the expression into a string. They can interpret it any way they like. I strongly believe that this is going to allow for writing connectors to XML, input streams, maps, etc. (think LINQ). *) I added a sample code generator (in python) that generates table representations from a DDL Todo-List: ---------- *) More thorough documentation *) More thorough and easier to comprehend tests *) Some of you mentioned that Boost.Fusion or Boost.Preprocessor might do be able to do the job of code generation very elegantly. I won't do that myself but I'd be interested to see such solutions. Since code generation is not integral part of the library it would make sense to have such solutions as support libraries. *) Look into cursors FYI, I am going to give a talk about sqlpp11 and some template patterns used inside of it on February 27 in Munich, see http://www.meetup.com/MUCplusplus/events/160688442/ Please let me know your questions/thoughts/suggestions/rants. Contributions welcome, of course :-) Regards, Roland PS: Given enough interest, I intend to officially propose the library to boost (after several more iterations, of course). This is why I hope it is OK to discuss sqlpp11 on this mailing list every now and then.

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Regarding GSoC 2014
by shubhv＠iitk.ac.in 04 Feb '14

04 Feb '14

Hey, I am a sophomore student of Computer Science Department, IIT Kanpur, India. I have been going through the boost libraries for quite some time now, and also have read through the proposed GSoC projects in 2014. I am especially interested in the Boost.Math Generalized Hyper geometric Functions. Though I have gone through the links provided under that project and am trying to become versed with Boost's Math library, I am finding it difficult to find a starting point to contributing. I would be really glad if someone could help me in the initial phase by directing me to the right starting point and guide me through. Thanks Shubhangee Verma

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Trying modular Boost
by Paul A. Bristow 04 Feb '14

04 Feb '14

FWIW here are some things I didn't understand or did wrong. (And, of course, playing Devil's Decidedly Dumb Advocate ;-) 1 How do I know if I have the right version of Git? Open GitHub icon and check Tools/About? 2 Windows hint: If you install TortoiseGIT, avoid incompatibilities by using the command line version of Git that TortoiseGIT installs. I.E. place C:\Program Files (x86)\Git\cmd in your path ahead of any other git binaries, such as cygwin. Huh? Am I Shelling, Bashing, Batting or Powershelling? How do I do that? How do I check that I have done this right? Open a Windows command window? Many Windowers will not know how to find/edit their path (and should not need to know?). A link would help. If you have dozens of items in the path, this is pretty awkward to edit? But (after a frustrating failure to get SSH access to work - in a separate post) I got to the main course using https: https://github.com/boostorg/boost.git Submodule 'io' (https://github.com/boostorg/io.git) registered for path 'libs/io' Submodule 'iostreams' (https://github.com/boostorg/iostreams.git) registered for path 'libs/iostreams' <big snip> Cloning into 'tools/quickbook'... Submodule path 'tools/quickbook': checked out '340c65150d175ffc20a9a877247928b3ed5eba1b' Success (4040769 ms @ 31-Dec-2013 17:00:21) Just over an hour (using my nominal 10 mbps living-in-the-boondocks but line-of-sight radio link) - something that should be noted in the docs (along with a strong recommendation to send to a log file)? Other you would miss/lose this very useful info? Building the Boost C++ Libraries. Performing configuration checks - symlinks supported : no - hardlinks supported : yes - 32-bit : yes . And I could test system library OK J Phew! Paul PS I had an existing (luckily current) b2.exe at c:\program files\Boost and this is implicitly in my PATH. Do we need to be more specific about how b2 is stored and accessed? Some check that b2.exe vcvars32.bat etc are all set up correctly would be good? --- Paul A. Bristow, Prizet Farmhouse, Kendal LA8 8AB UK +44 1539 561830 07714330204 <mailto:pbristow@hetp.u-net.com> pbristow(a)hetp.u-net.com

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