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  • Method flags as arguments or as member variables?

    - by Martin
    I think the title "Method flags as arguments or as member variables?" may be suboptimal, but as I'm missing any better terminology atm., here goes: I'm currently trying to get my head around the problem of whether flags for a given class (private) method should be passed as function arguments or via member variable and/or whether there is some pattern or name that covers this aspect and/or whether this hints at some other design problems. By example (language could be C++, Java, C#, doesn't really matter IMHO): class Thingamajig { private ResultType DoInternalStuff(FlagType calcSelect) { ResultType res; for (... some loop condition ...) { ... if (calcSelect == typeA) { ... } else if (calcSelect == typeX) { ... } else if ... } ... return res; } private void InteralStuffInvoker(FlagType calcSelect) { ... DoInternalStuff(calcSelect); ... } public void DoThisStuff() { ... some code ... InternalStuffInvoker(typeA); ... some more code ... } public ResultType DoThatStuff() { ... some code ... ResultType x = DoInternalStuff(typeX); ... some more code ... further process x ... return x; } } What we see above is that the method InternalStuffInvoker takes an argument that is not used inside this function at all but is only forwarded to the other private method DoInternalStuff. (Where DoInternalStuffwill be used privately at other places in this class, e.g. in the DoThatStuff (public) method.) An alternative solution would be to add a member variable that carries this information: class Thingamajig { private ResultType DoInternalStuff() { ResultType res; for (... some loop condition ...) { ... if (m_calcSelect == typeA) { ... } ... } ... return res; } private void InteralStuffInvoker() { ... DoInternalStuff(); ... } public void DoThisStuff() { ... some code ... m_calcSelect = typeA; InternalStuffInvoker(); ... some more code ... } public ResultType DoThatStuff() { ... some code ... m_calcSelect = typeX; ResultType x = DoInternalStuff(); ... some more code ... further process x ... return x; } } Especially for deep call chains where the selector-flag for the inner method is selected outside, using a member variable can make the intermediate functions cleaner, as they don't need to carry a pass-through parameter. On the other hand, this member variable isn't really representing any object state (as it's neither set nor available outside), but is really a hidden additional argument for the "inner" private method. What are the pros and cons of each approach?

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  • Solaris 11.1 changes building of code past the point of __NORETURN

    - by alanc
    While Solaris 11.1 was under development, we started seeing some errors in the builds of the upstream X.Org git master sources, such as: "Display.c", line 65: Function has no return statement : x_io_error_handler "hostx.c", line 341: Function has no return statement : x_io_error_handler from functions that were defined to match a specific callback definition that declared them as returning an int if they did return, but these were calling exit() instead of returning so hadn't listed a return value. These had been generating warnings for years which we'd been ignoring, but X.Org has made enough progress in cleaning up code for compiler warnings and static analysis issues lately, that the community turned up the default error levels, including the gcc flag -Werror=return-type and the equivalent Solaris Studio cc flags -v -errwarn=E_FUNC_HAS_NO_RETURN_STMT, so now these became errors that stopped the build. Yet on Solaris, gcc built this code fine, while Studio errored out. Investigation showed this was due to the Solaris headers, which during Solaris 10 development added a number of annotations to the headers when gcc was being used for the amd64 kernel bringup before the Studio amd64 port was ready. Since Studio did not support the inline form of these annotations at the time, but instead used #pragma for them, the definitions were only present for gcc. To resolve this, I fixed both sides of the problem, so that it would work for building new X.Org sources on older Solaris releases or with older Studio compilers, as well as fixing the general problem before it broke more software building on Solaris. To the X.Org sources, I added the traditional Studio #pragma does_not_return to recognize that functions like exit() don't ever return, in patches such as this Xserver patch. Adding a dummy return statement was ruled out as that introduced unreachable code errors from compilers and analyzers that correctly realized you couldn't reach that code after a return statement. And on the Solaris 11.1 side, I updated the annotation definitions in <sys/ccompile.h> to enable for Studio 12.0 and later compilers the annotations already existing in a number of system headers for functions like exit() and abort(). If you look in that file you'll see the annotations we currently use, though the forms there haven't gone through review to become a Committed interface, so may change in the future. Actually getting this integrated into Solaris though took a bit more work than just editing one header file. Our ELF binary build comparison tool, wsdiff, actually showed a large number of differences in the resulting binaries due to the compiler using this information for branch prediction, code path analysis, and other possible optimizations, so after comparing enough of the disassembly output to be comfortable with the changes, we also made sure to get this in early enough in the release cycle so that it would get plenty of test exposure before the release. It also required updating quite a bit of code to avoid introducing new lint or compiler warnings or errors, and people building applications on top of Solaris 11.1 and later may need to make similar changes if they want to keep their build logs similarly clean. Previously, if you had a function that was declared with a non-void return type, lint and cc would warn if you didn't return a value, even if you called a function like exit() or panic() that ended execution. For instance: #include <stdlib.h> int callback(int status) { if (status == 0) return status; exit(status); } would previously require a never executed return 0; after the exit() to avoid lint warning "function falls off bottom without returning value". Now the compiler & lint will both issue "statement not reached" warnings for a return 0; after the final exit(), allowing (or in some cases, requiring) it to be removed. However, if there is no return statement anywhere in the function, lint will warn that you've declared a function returning a value that never does so, suggesting you can declare it as void. Unfortunately, if your function signature is required to match a certain form, such as in a callback, you not be able to do so, and will need to add a /* LINTED */ to the end of the function. If you need your code to build on both a newer and an older release, then you will either need to #ifdef these unreachable statements, or, to keep your sources common across releases, add to your sources the corresponding #pragma recognized by both current and older compiler versions, such as: #pragma does_not_return(exit) #pragma does_not_return(panic) Hopefully this little extra work is paid for by the compilers & code analyzers being able to better understand your code paths, giving you better optimizations and more accurate errors & warning messages.

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  • Creating New Scripts Dynamically in Lua

    - by bazola
    Right now this is just a crazy idea that I had, but I was able to implement the code and get it working properly. I am not entirely sure of what the use cases would be just yet. What this code does is create a new Lua script file in the project directory. The ScriptWriter takes as arguments the file name, a table containing any arguments that the script should take when created, and a table containing any instance variables to create by default. My plan is to extend this code to create new functions based on inputs sent in during its creation as well. What makes this cool is that the new file is both generated and loaded dynamically on the fly. Theoretically you could get this code to generate and load any script imaginable. One use case I can think of is an AI that creates scripts to map out it's functions, and creates new scripts for new situations or environments. At this point, this is all theoretical, though. Here is the test code that is creating the new script and then immediately loading it and calling functions from it: function Card:doScriptWriterThing() local scriptName = "ScriptIAmMaking" local scripter = scriptWriter:new(scriptName, {"argumentName"}, {name = "'test'", one = 1}) scripter:makeFileForLoadedSettings() local loadedScript = require (scriptName) local scriptInstance = loadedScript:new("sayThis") print(scriptInstance:get_name()) --will print test print(scriptInstance:get_one()) -- will print 1 scriptInstance:set_one(10000) print(scriptInstance:get_one()) -- will print 10000 print(scriptInstance:get_argumentName()) -- will print sayThis scriptInstance:set_argumentName("saySomethingElse") print(scriptInstance:get_argumentName()) --will print saySomethingElse end Here is ScriptWriter.lua local ScriptWriter = {} local twoSpaceIndent = " " local equalsWithSpaces = " = " local newLine = "\n" --scriptNameToCreate must be a string --argumentsForNew and instanceVariablesToCreate must be tables and not nil function ScriptWriter:new(scriptNameToCreate, argumentsForNew, instanceVariablesToCreate) local instance = setmetatable({}, { __index = self }) instance.name = scriptNameToCreate instance.newArguments = argumentsForNew instance.instanceVariables = instanceVariablesToCreate instance.stringList = {} return instance end function ScriptWriter:makeFileForLoadedSettings() self:buildInstanceMetatable() self:buildInstanceCreationMethod() self:buildSettersAndGetters() self:buildReturn() self:writeStringsToFile() end --very first line of any script that will have instances function ScriptWriter:buildInstanceMetatable() table.insert(self.stringList, "local " .. self.name .. " = {}" .. newLine) table.insert(self.stringList, newLine) end --every script made this way needs a new method to create its instances function ScriptWriter:buildInstanceCreationMethod() --new() function declaration table.insert(self.stringList, ("function " .. self.name .. ":new(")) self:buildNewArguments() table.insert(self.stringList, ")" .. newLine) --first line inside :new() function table.insert(self.stringList, twoSpaceIndent .. "local instance = setmetatable({}, { __index = self })" .. newLine) --add designated arguments inside :new() self:buildNewArgumentVariables() --create the instance variables with the loaded values for key,value in pairs(self.instanceVariables) do table.insert(self.stringList, twoSpaceIndent .. "instance." .. key .. equalsWithSpaces .. value .. newLine) end --close the :new() function table.insert(self.stringList, twoSpaceIndent .. "return instance" .. newLine) table.insert(self.stringList, "end" .. newLine) table.insert(self.stringList, newLine) end function ScriptWriter:buildNewArguments() --if there are arguments for :new(), add them for key,value in ipairs(self.newArguments) do table.insert(self.stringList, value) table.insert(self.stringList, ", ") end if next(self.newArguments) ~= nil then --makes sure the table is not empty first table.remove(self.stringList) --remove the very last element, which will be the extra ", " end end function ScriptWriter:buildNewArgumentVariables() --add the designated arguments to :new() for key, value in ipairs(self.newArguments) do table.insert(self.stringList, twoSpaceIndent .. "instance." .. value .. equalsWithSpaces .. value .. newLine) end end --the instance variables need separate code because their names have to be the key and not the argument name function ScriptWriter:buildSettersAndGetters() for key,value in ipairs(self.newArguments) do self:buildArgumentSetter(value) self:buildArgumentGetter(value) table.insert(self.stringList, newLine) end for key,value in pairs(self.instanceVariables) do self:buildInstanceVariableSetter(key, value) self:buildInstanceVariableGetter(key, value) table.insert(self.stringList, newLine) end end --code for arguments passed in function ScriptWriter:buildArgumentSetter(variable) table.insert(self.stringList, "function " .. self.name .. ":set_" .. variable .. "(newValue)" .. newLine) table.insert(self.stringList, twoSpaceIndent .. "self." .. variable .. equalsWithSpaces .. "newValue" .. newLine) table.insert(self.stringList, "end" .. newLine) end function ScriptWriter:buildArgumentGetter(variable) table.insert(self.stringList, "function " .. self.name .. ":get_" .. variable .. "()" .. newLine) table.insert(self.stringList, twoSpaceIndent .. "return " .. "self." .. variable .. newLine) table.insert(self.stringList, "end" .. newLine) end --code for instance variable values passed in function ScriptWriter:buildInstanceVariableSetter(key, variable) table.insert(self.stringList, "function " .. self.name .. ":set_" .. key .. "(newValue)" .. newLine) table.insert(self.stringList, twoSpaceIndent .. "self." .. key .. equalsWithSpaces .. "newValue" .. newLine) table.insert(self.stringList, "end" .. newLine) end function ScriptWriter:buildInstanceVariableGetter(key, variable) table.insert(self.stringList, "function " .. self.name .. ":get_" .. key .. "()" .. newLine) table.insert(self.stringList, twoSpaceIndent .. "return " .. "self." .. key .. newLine) table.insert(self.stringList, "end" .. newLine) end --last line of any script that will have instances function ScriptWriter:buildReturn() table.insert(self.stringList, "return " .. self.name) end function ScriptWriter:writeStringsToFile() local fileName = (self.name .. ".lua") file = io.open(fileName, 'w') for key,value in ipairs(self.stringList) do file:write(value) end file:close() end return ScriptWriter And here is what the code provided will generate: local ScriptIAmMaking = {} function ScriptIAmMaking:new(argumentName) local instance = setmetatable({}, { __index = self }) instance.argumentName = argumentName instance.name = 'test' instance.one = 1 return instance end function ScriptIAmMaking:set_argumentName(newValue) self.argumentName = newValue end function ScriptIAmMaking:get_argumentName() return self.argumentName end function ScriptIAmMaking:set_name(newValue) self.name = newValue end function ScriptIAmMaking:get_name() return self.name end function ScriptIAmMaking:set_one(newValue) self.one = newValue end function ScriptIAmMaking:get_one() return self.one end return ScriptIAmMaking All of this is generated with these calls: local scripter = scriptWriter:new(scriptName, {"argumentName"}, {name = "'test'", one = 1}) scripter:makeFileForLoadedSettings() I am not sure if I am correct that this could be useful in certain situations. What I am looking for is feedback on the readability of the code, and following Lua best practices. I would also love to hear whether this approach is a valid one, and whether the way that I have done things will be extensible.

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  • Qt : Nokia proposera démos et conférence lors du rts EMBEDDED SYSTEMS de Paris du 30 au 31 Mars proc

    Nokia proposera des démos de Qt lors du rts EMBEDDED SYSTEMS Du 30 au 31 Mars à la Porte de Versailles Nokia sera présent lors du rts EMBEDDED SYSTEMS, 18ème édition du salon des Solutions informatiques temps-réel et systèmes embarqués. Sur son stand (#A20) le constructeur proposera des démos de Qt et le mercredi 31 mars, à 13h, Thierry Bastian, Software Engineer, tiendra une conférence pour présenter le framework multi-plateformes. La manifestation se tiendra à la Porte de Versailles à Paris. Plus d'informations et les modalités pour s'inscrire sur cette page....

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  • Qt : Nokia proposera démos et conférence lors du rts EMBEDDED SYSTEMS de Paris du 30 au 31 Mars proc

    Nokia proposera des démos de Qt lors du rts EMBEDDED SYSTEMS Du 30 au 31 Mars à la Porte de Versailles Nokia sera présent lors du rts EMBEDDED SYSTEMS, 18ème édition du salon des Solutions informatiques temps-réel et systèmes embarqués. Sur son stand (#A20) le constructeur proposera des démos de Qt et le mercredi 31 mars, à 13h, Thierry Bastian, Software Engineer, tiendra une conférence pour présenter le framework multi-plateformes. La manifestation se tiendra à la Porte de Versailles à Paris. Plus d'informations et les modalités pour s'inscrire sur cette page....

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  • Windows Embedded Standard 8 : la CTP 2 disponible, 6.000 développeurs utiliseraient déjà l'OS embarqué dérivé de Windows 8

    Windows Embedded Standard 8 : la deuxième CTP disponible Plus de 6 000 développeurs utilisent déjà l'OS embarqué dérivé de Windows 8 Mise à jour du 07/06/12 Hier, au salon Computex de Taïwan, Steven Guggenheimer, vice-président du service OEM de Microsoft, est monté sur scène pour présenter les dernières technologies de Microsoft sur les « systèmes intelligents » (appareils qui embarquent un OS et qui permettent de se connecter à des terminaux spécialisés ou à des services en ligne comme des serveurs distants ou des bases de données). Il en a profité pour annoncer la disponibilité de la deuxième community technology preview (CTP) de Windows Embedded Standard 8...

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  • Windows Embedded 8 sortira en mars 2013, Microsoft publie la Roadmap et une préversion de son OS embarqué, fondé sur Windows 8

    Windows Embedded Standard 8 : la deuxième CTP disponible Plus de 6 000 développeurs utilisent déjà l'OS embarqué dérivé de Windows 8 Mise à jour du 07/06/12 Hier, au salon Computex de Taïwan, Steven Guggenheimer, vice-président du service OEM de Microsoft, est monté sur scène pour présenter les dernières technologies de Microsoft sur les « systèmes intelligents » (appareils qui embarquent un OS et qui permettent de se connecter à des terminaux spécialisés ou à des services en ligne comme des serveurs distants ou des bases de données). Il en a profité pour annoncer la disponibilité de la deuxième community technology preview (CTP) de Windows Embedded Standard 8...

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  • Windows 8 Embedded preview sera publié au premier trimestre 2012, la version finale disponible trois mois après la sortie de Windows 8

    Windows 8 Embedded : la préversion de l'OS sera publiée au premier trimestre 2012 La version finale sera disponible trois trimestres après la sortie de Windows 8 Microsoft prévoit de mettre à la disposition des développeurs une préversion de Windows 8 Embedded, son OS pour l'embarqué pendant le premier trimestre de l'année prochaine. La prochaine version du système sera développée suivant une approche plus agile, ciblée et moins monolithique. Elle a pour vocation d'étendre les solutions d'entreprises et les services Cloud aux appareils de la vie quotidienne, tels que les terminaux de points de service, les systèmes d'info loisirs automobiles, les équipements médicaux, les machines...

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  • HttpWebRequest: How to find a postal code at Canada Post through a WebRequest with x-www-form-enclos

    - by Will Marcouiller
    I'm currently writing some tests so that I may improve my skills with the Internet interaction through Windows Forms. One of those tests is to find a postal code which should be returned by Canada Post website. My default URL setting is set to: http://www.canadapost.ca/cpotools/apps/fpc/personal/findByCity?execution=e4s1 The required form fields are: streetNumber, streetName, city, province The contentType is "application/x-www-form-enclosed" EDIT: Please consider the value "application/x-www-form-encoded" instead of point 3 value as the contentType. (Thanks EricLaw-MSFT!) The result I get is not the result expected. I get the HTML source code of the page where I could manually enter the information to find the postal code, but not the HTML source code with the found postal code. Any idea of what I'm doing wrong? Shall I consider going the XML way? Is it first of all possible to search on Canada Post anonymously? Here's a code sample for better description: public static string FindPostalCode(ICanadadianAddress address) { var postData = string.Concat(string.Format("&streetNumber={0}", address.StreetNumber) , string.Format("&streetName={0}", address.StreetName) , string.Format("&city={0}", address.City) , string.Format("&province={0}", address.Province)); var encoding = new ASCIIEncoding(); byte[] postDataBytes = encoding.GetBytes(postData); request = (HttpWebRequest)WebRequest.Create(DefaultUrlSettings); request.ImpersonationLevel = System.Security.Principal.TokenImpersonationLevel.Anonymous; request.Container = new CookieContainer(); request.Timeout = 10000; request.ContentType = contentType; request.ContentLength = postDataBytes.LongLength; request.Method = @"post"; var senderStream = new StreamWriter(request.GetRequestStream()); senderStream.Write(postDataBytes, 0, postDataBytes.Length); senderStream.Close(); string htmlResponse = new StreamReader(request.GetResponse().GetResponseStream()).ReadToEnd(); return processedResult(htmlResponse); // Processing the HTML source code parsing, etc. } I seem stuck in a bottle neck in my point of view. I find no way out to the desired result. EDIT: There seems to have to parameters as for the ContentType of this site. Let me explain. There's one with the "meta"-variables which stipulates the following: meta http-equiv="Content-Type" content="application/xhtml+xml, text/xml, text/html; charset=utf-8" And another one later down the code that is read as: form id="fpcByAdvancedSearch:fpcSearch" name="fpcByAdvancedSearch:fpcSearch" method="post" action="/cpotools/apps/fpc/personal/findByCity?execution=e1s1" enctype="application/x-www-form-urlencoded" My question is the following: With which one do I have to stick? Let me guess, the first ContentType is to be considered as the second is only for another request to a function or so when the data is posted? EDIT: As per request, the closer to the solution I am is listed under this question: WebRequest: How to find a postal code using a WebRequest against this ContentType=”application/xhtml+xml, text/xml, text/html; charset=utf-8”? Thanks for any help! :-)

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  • Refactor This (Ugly Code)!

    - by Alois Kraus
    Ayende has put on his blog some ugly code to refactor. First and foremost it is nearly impossible to reason about other peoples code without knowing the driving forces behind the current code. It is certainly possible to make it much cleaner when potential sources of errors cannot happen in the first place due to good design. I can see what the intention of the code is but I do not know about every brittle detail if I am allowed to reorder things here and there to simplify things. So I decided to make it much simpler by identifying the different responsibilities of the methods and encapsulate it in different classes. The code we need to refactor seems to deal with a handler after a message has been sent to a message queue. The handler does complete the current transaction if there is any and does handle any errors happening there. If during the the completion of the transaction errors occur the transaction is at least disposed. We can enter the handler already in a faulty state where we try to deliver the complete event in any case and signal a failure event and try to resend the message again to the queue if it was not inside a transaction. All is decorated with many try/catch blocks, duplicated code and some state variables to route the program flow. It is hard to understand and difficult to reason about. In other words: This code is a mess and could be written by me if I was under pressure. Here comes to code we want to refactor:         private void HandleMessageCompletion(                                      Message message,                                      TransactionScope tx,                                      OpenedQueue messageQueue,                                      Exception exception,                                      Action<CurrentMessageInformation, Exception> messageCompleted,                                      Action<CurrentMessageInformation> beforeTransactionCommit)         {             var txDisposed = false;             if (exception == null)             {                 try                 {                     if (tx != null)                     {                         if (beforeTransactionCommit != null)                             beforeTransactionCommit(currentMessageInformation);                         tx.Complete();                         tx.Dispose();                         txDisposed = true;                     }                     try                     {                         if (messageCompleted != null)                             messageCompleted(currentMessageInformation, exception);                     }                     catch (Exception e)                     {                         Trace.TraceError("An error occured when raising the MessageCompleted event, the error will NOT affect the message processing"+ e);                     }                     return;                 }                 catch (Exception e)                 {                     Trace.TraceWarning("Failed to complete transaction, moving to error mode"+ e);                     exception = e;                 }             }             try             {                 if (txDisposed == false && tx != null)                 {                     Trace.TraceWarning("Disposing transaction in error mode");                     tx.Dispose();                 }             }             catch (Exception e)             {                 Trace.TraceWarning("Failed to dispose of transaction in error mode."+ e);             }             if (message == null)                 return;                 try             {                 if (messageCompleted != null)                     messageCompleted(currentMessageInformation, exception);             }             catch (Exception e)             {                 Trace.TraceError("An error occured when raising the MessageCompleted event, the error will NOT affect the message processing"+ e);             }               try             {                 var copy = MessageProcessingFailure;                 if (copy != null)                     copy(currentMessageInformation, exception);             }             catch (Exception moduleException)             {                 Trace.TraceError("Module failed to process message failure: " + exception.Message+                                              moduleException);             }               if (messageQueue.IsTransactional == false)// put the item back in the queue             {                 messageQueue.Send(message);             }         }     You can see quite some processing and handling going on there. Yes this looks like real world code one did put together to make things work and he does not trust his callbacks. I guess these are event handlers which are optional and the delegates were extracted from an event to call them back later when necessary.  Lets see what the author of this code did intend:          private void HandleMessageCompletion(             TransactionHandler transactionHandler,             MessageCompletionHandler handler,             CurrentMessageInformation messageInfo,             ErrorCollector errors             )         {               // commit current pending transaction             transactionHandler.CallHandlerAndCommit(messageInfo, errors);               // We have an error for a null message do not send completion event             if (messageInfo.CurrentMessage == null)                 return;               // Send completion event in any case regardless of errors             handler.OnMessageCompleted(messageInfo, errors);               // put message back if queue is not transactional             transactionHandler.ResendMessageOnError(messageInfo.CurrentMessage, errors);         }   I did not bother to write the intention here again since the code should be pretty self explaining by now. I have used comments to explain the still nontrivial procedure step by step revealing the real intention about all this complex program flow. The original complexity of the problem domain does not go away but by applying the techniques of SRP (Single Responsibility Principle) and some functional style but we can abstract the necessary complexity away in useful abstractions which make it much easier to reason about it. Since most of the method seems to deal with errors I thought it was a good idea to encapsulate the error state of our current message in an ErrorCollector object which stores all exceptions in a list along with a description what the error all was about in the exception itself. We can log it later or not depending on the log level or whatever. It is really just a simple list that encapsulates the current error state.          class ErrorCollector          {              List<Exception> _Errors = new List<Exception>();                public void Add(Exception ex, string description)              {                  ex.Data["Description"] = description;                  _Errors.Add(ex);              }                public Exception Last              {                  get                  {                      return _Errors.LastOrDefault();                  }              }                public bool HasError              {                  get                  {                      return _Errors.Count > 0;                  }              }          }   Since the error state is global we have two choices to store a reference in the other helper objects (TransactionHandler and MessageCompletionHandler)or pass it to the method calls when necessary. I did chose the latter one because a second argument does not hurt and makes it easier to reason about the overall state while the helper objects remain stateless and immutable which makes the helper objects much easier to understand and as a bonus thread safe as well. This does not mean that the stored member variables are stateless or thread safe as well but at least our helper classes are it. Most of the complexity is located the transaction handling I consider as a separate responsibility that I delegate to the TransactionHandler which does nothing if there is no transaction or Call the Before Commit Handler Commit Transaction Dispose Transaction if commit did throw In fact it has a second responsibility to resend the message if the transaction did fail. I did see a good fit there since it deals with transaction failures.          class TransactionHandler          {              TransactionScope _Tx;              Action<CurrentMessageInformation> _BeforeCommit;              OpenedQueue _MessageQueue;                public TransactionHandler(TransactionScope tx, Action<CurrentMessageInformation> beforeCommit, OpenedQueue messageQueue)              {                  _Tx = tx;                  _BeforeCommit = beforeCommit;                  _MessageQueue = messageQueue;              }                public void CallHandlerAndCommit(CurrentMessageInformation currentMessageInfo, ErrorCollector errors)              {                  if (_Tx != null && !errors.HasError)                  {                      try                      {                          if (_BeforeCommit != null)                          {                              _BeforeCommit(currentMessageInfo);                          }                            _Tx.Complete();                          _Tx.Dispose();                      }                      catch (Exception ex)                      {                          errors.Add(ex, "Failed to complete transaction, moving to error mode");                          Trace.TraceWarning("Disposing transaction in error mode");                          try                          {                              _Tx.Dispose();                          }                          catch (Exception ex2)                          {                              errors.Add(ex2, "Failed to dispose of transaction in error mode.");                          }                      }                  }              }                public void ResendMessageOnError(Message message, ErrorCollector errors)              {                  if (errors.HasError && !_MessageQueue.IsTransactional)                  {                      _MessageQueue.Send(message);                  }              }          } If we need to change the handling in the future we have a much easier time to reason about our application flow than before. After we did complete our transaction and called our callback we can call the completion handler which is the main purpose of the HandleMessageCompletion method after all. The responsiblity o the MessageCompletionHandler is to call the completion callback and the failure callback when some error has occurred.            class MessageCompletionHandler          {              Action<CurrentMessageInformation, Exception> _MessageCompletedHandler;              Action<CurrentMessageInformation, Exception> _MessageProcessingFailure;                public MessageCompletionHandler(Action<CurrentMessageInformation, Exception> messageCompletedHandler,                                              Action<CurrentMessageInformation, Exception> messageProcessingFailure)              {                  _MessageCompletedHandler = messageCompletedHandler;                  _MessageProcessingFailure = messageProcessingFailure;              }                  public void OnMessageCompleted(CurrentMessageInformation currentMessageInfo, ErrorCollector errors)              {                  try                  {                      if (_MessageCompletedHandler != null)                      {                          _MessageCompletedHandler(currentMessageInfo, errors.Last);                      }                  }                  catch (Exception ex)                  {                      errors.Add(ex, "An error occured when raising the MessageCompleted event, the error will NOT affect the message processing");                  }                    if (errors.HasError)                  {                      SignalFailedMessage(currentMessageInfo, errors);                  }              }                void SignalFailedMessage(CurrentMessageInformation currentMessageInfo, ErrorCollector errors)              {                  try                  {                      if (_MessageProcessingFailure != null)                          _MessageProcessingFailure(currentMessageInfo, errors.Last);                  }                  catch (Exception moduleException)                  {                      errors.Add(moduleException, "Module failed to process message failure");                  }              }            }   If for some reason I did screw up the logic and we need to call the completion handler from our Transaction handler we can simple add to the CallHandlerAndCommit method a third argument to the MessageCompletionHandler and we are fine again. If the logic becomes even more complex and we need to ensure that the completed event is triggered only once we have now one place the completion handler to capture the state. During this refactoring I simple put things together that belong together and came up with useful abstractions. If you look at the original argument list of the HandleMessageCompletion method I have put many things together:   Original Arguments New Arguments Encapsulate Message message CurrentMessageInformation messageInfo         Message message TransactionScope tx Action<CurrentMessageInformation> beforeTransactionCommit OpenedQueue messageQueue TransactionHandler transactionHandler        TransactionScope tx        OpenedQueue messageQueue        Action<CurrentMessageInformation> beforeTransactionCommit Exception exception,             ErrorCollector errors Action<CurrentMessageInformation, Exception> messageCompleted MessageCompletionHandler handler          Action<CurrentMessageInformation, Exception> messageCompleted          Action<CurrentMessageInformation, Exception> messageProcessingFailure The reason is simple: Put the things that have relationships together and you will find nearly automatically useful abstractions. I hope this makes sense to you. If you see a way to make it even more simple you can show Ayende your improved version as well.

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  • Building Publishing Pages in Code

    - by David Jacobus
    Originally posted on: http://geekswithblogs.net/djacobus/archive/2013/10/27/154478.aspxOne of the Mantras we developers try to follow: Ensure that the solution package we deliver to the client is complete.  We build Web Parts, Master Pages, Images, CSS files and other artifacts that we push to the client with a WSP (Solution Package) And then we have them finish the solution by building their site pages by adding the web parts to the site pages.       I am a proponent that we,  the developers,  should minimize this time consuming work and build these site pages in code.  I found a few blogs and some MSDN documentation but not really a complete solution that has all these artifacts working in one solution.   What I am will discuss and provide a solution for is a package that has: 1.  Master Page 2.  Page Layout 3.  Page Web Parts 4.  Site Pages   Most all done in code without the development team or the developers having to finish up the site building process spending a few hours or days completing the site!  I am not implying that in Development we do this. In fact,  we build these pages incrementally testing our web parts, etc. I am saying that the final action in our solution is that we take all these artifacts and add them to the site pages in code, the client then only needs to activate a few features and VIOLA their site appears!.  I had a project that had me build 8 pages like this as part of the solution.   In this blog post, I am taking a master page solution that I have called DJGreenMaster.  On My Office 365 Development Site it looks like this:     It is a generic master page for a SharePoint 2010 site Along with a three column layout.  Centered with a footer that uses a SharePoint List and Web Part for the footer links.  I use this master page a lot in my site development!  Easy to change the color and site logo with a little CSS.   I am going to add a few web parts for discussion purposes and then add these web parts to a site page in code.    Lets look at the solution package for DJ Green Master as that will be the basis project for building the site pages:   What you are seeing  is a complete solution to add a Master Page to a site collection which contains: 1.  Master Page Module which contains the Master Page and Page Layout 2.  The Footer Module to add the Footer Web Part 3.  Miscellaneous modules to add images, JQuery, CSS and subsite page 4.  3 features and two feature event receivers: a.  DJGreenCSS, used to add the master page CSS file to Style Sheet Library and an Event Receiver to check it in. b.  DJGreenMaster used to add the Master Page and Page Layout.  In an Event Receiver change the master page to DJGreenMaster , create the footer list and check the files in. c.  DJGreenMasterWebParts add the Footer Web Part to the site collection. I won’t go over the code for this as I will give it to you at the end of this blog post. I have discussed creating a list in code in a previous post.  So what we have is the basis to begin what is germane to this discussion.  I have the first two requirements completed.  I need now to add page web parts and the build the pages in code.  For the page web parts, I will use one downloaded from Codeplex which does not use a SharePoint custom list for simplicity:   Weather Web Part and another downloaded from MSDN which is a SharePoint Custom Calendar Web Part, I had to add some functionality to make the events color coded to exceed the built-in 10 overlays using JQuery!    Here is the solution with the added projects:     Here is a screen shot of the Weather Web Part Deployed:   Here is a screen shot of the Site Calendar with JQuery:     Okay, Now we get to the final item:  To create Publishing pages.   We need to add a feature receiver to the DJGreenMaster project I will name it DJSitePages and also add a Event Receiver:       We will build the page at the site collection level and all of the code necessary will be contained in the event receiver.   Added a reference to the Microsoft.SharePoint.Publishing.dll contained in the ISAPI folder of the 14 Hive.   First we will add some static methods from which we will call  in our Event Receiver:   1: private static void checkOut(string pagename, PublishingPage p) 2: { 3: if (p.Name.Equals(pagename, StringComparison.InvariantCultureIgnoreCase)) 4: { 5: 6: if (p.ListItem.File.CheckOutType == SPFile.SPCheckOutType.None) 7: { 8: p.CheckOut(); 9: } 10:   11: if (p.ListItem.File.CheckOutType == SPFile.SPCheckOutType.Online) 12: { 13: p.CheckIn("initial"); 14: p.CheckOut(); 15: } 16: } 17: } 18: private static void checkin(PublishingPage p,PublishingWeb pw) 19: { 20: SPFile publishFile = p.ListItem.File; 21:   22: if (publishFile.CheckOutType != SPFile.SPCheckOutType.None) 23: { 24:   25: publishFile.CheckIn( 26:   27: "CheckedIn"); 28:   29: publishFile.Publish( 30:   31: "published"); 32: } 33: // In case of content approval, approve the file need to add 34: //pulishing site 35: if (pw.PagesList.EnableModeration) 36: { 37: publishFile.Approve("Initial"); 38: } 39: publishFile.Update(); 40: }   In a Publishing Site, CheckIn and CheckOut  are required when dealing with pages in a publishing site.  Okay lets look at the Feature Activated Event Receiver: 1: public override void FeatureActivated(SPFeatureReceiverProperties properties) 2: { 3:   4:   5:   6: object oParent = properties.Feature.Parent; 7:   8:   9:   10: if (properties.Feature.Parent is SPWeb) 11: { 12:   13: currentWeb = (SPWeb)oParent; 14:   15: currentSite = currentWeb.Site; 16:   17: } 18:   19: else 20: { 21:   22: currentSite = (SPSite)oParent; 23:   24: currentWeb = currentSite.RootWeb; 25:   26: } 27: 28:   29: //create the publishing pages 30: CreatePublishingPage(currentWeb, "Home.aspx", "ThreeColumnLayout.aspx","Home"); 31: //CreatePublishingPage(currentWeb, "Dummy.aspx", "ThreeColumnLayout.aspx","Dummy"); 32: }     Basically we are calling the method Create Publishing Page with parameters:  Current Web, Name of the Page, The Page Layout, Title of the page.  Let’s look at the Create Publishing Page method:   1:   2: private void CreatePublishingPage(SPWeb site, string pageName, string pageLayoutName, string title) 3: { 4: PublishingSite pubSiteCollection = new PublishingSite(site.Site); 5: PublishingWeb pubSite = null; 6: if (pubSiteCollection != null) 7: { 8: // Assign an object to the pubSite variable 9: if (PublishingWeb.IsPublishingWeb(site)) 10: { 11: pubSite = PublishingWeb.GetPublishingWeb(site); 12: } 13: } 14: // Search for the page layout for creating the new page 15: PageLayout currentPageLayout = FindPageLayout(pubSiteCollection, pageLayoutName); 16: // Check or the Page Layout could be found in the collection 17: // if not (== null, return because the page has to be based on 18: // an excisting Page Layout 19: if (currentPageLayout == null) 20: { 21: return; 22: } 23:   24: 25: PublishingPageCollection pages = pubSite.GetPublishingPages(); 26: foreach (PublishingPage p in pages) 27: { 28: //The page allready exists 29: if ((p.Name == pageName)) return; 30:   31: } 32: 33:   34:   35: PublishingPage newPage = pages.Add(pageName, currentPageLayout); 36: newPage.Description = pageName.Replace(".aspx", ""); 37: // Here you can set some properties like: 38: newPage.IncludeInCurrentNavigation = true; 39: newPage.IncludeInGlobalNavigation = true; 40: newPage.Title = title; 41: 42: 43:   44:   45: 46:   47: //build the page 48:   49: 50: switch (pageName) 51: { 52: case "Homer.aspx": 53: checkOut("Courier.aspx", newPage); 54: BuildHomePage(site, newPage); 55: break; 56:   57:   58: default: 59: break; 60: } 61: // newPage.Update(); 62: //Now we can checkin the newly created page to the “pages” library 63: checkin(newPage, pubSite); 64: 65: 66: }     The narrative in what is going on here is: 1.  We need to find out if we are dealing with a Publishing Web.  2.  Get the Page Layout 3.  Create the Page in the pages list. 4.  Based on the page name we build that page.  (Here is where we can add all the methods to build multiple pages.) In the switch we call Build Home Page where all the work is done to add the web parts.  Prior to adding the web parts we need to add references to the two web part projects in the solution. using WeatherWebPart.WeatherWebPart; using CSSharePointCustomCalendar.CustomCalendarWebPart;   We can then reference them in the Build Home Page method.   Let’s look at Build Home Page: 1:   2: private static void BuildHomePage(SPWeb web, PublishingPage pubPage) 3: { 4: // build the pages 5: // Get the web part manager for each page and do the same code as below (copy and paste, change to the web parts for the page) 6: // Part Description 7: SPLimitedWebPartManager mgr = web.GetLimitedWebPartManager(web.Url + "/Pages/Home.aspx", System.Web.UI.WebControls.WebParts.PersonalizationScope.Shared); 8: WeatherWebPart.WeatherWebPart.WeatherWebPart wwp = new WeatherWebPart.WeatherWebPart.WeatherWebPart() { ChromeType = PartChromeType.None, Title = "Todays Weather", AreaCode = "2504627" }; 9: //Dictionary<string, string> wwpDic= new Dictionary<string, string>(); 10: //wwpDic.Add("AreaCode", "2504627"); 11: //setWebPartProperties(wwp, "WeatherWebPart", wwpDic); 12:   13: // Add the web part to a pagelayout Web Part Zone 14: mgr.AddWebPart(wwp, "g_685594D193AA4BBFABEF2FB0C8A6C1DD", 1); 15:   16: CSSharePointCustomCalendar.CustomCalendarWebPart.CustomCalendarWebPart cwp = new CustomCalendarWebPart() { ChromeType = PartChromeType.None, Title = "Corporate Calendar", listName="CorporateCalendar" }; 17:   18: mgr.AddWebPart(cwp, "g_20CBAA1DF45949CDA5D351350462E4C6", 1); 19:   20:   21: pubPage.Update(); 22:   23: } Here is what we are doing: 1.  We got  a reference to the SharePoint Limited Web Part Manager and linked/referenced Home.aspx  2.  Instantiated the a new Weather Web Part and used the Manager to add it to the page in a web part zone identified by ID,  thus the need for a Page Layout where the developer knows the ID’s. 3.  Instantiated the Calendar Web Part and used the Manager to add it to the page. 4. We the called the Publishing Page update method. 5.  Lastly, the Create Publishing Page method checks in the page just created.   Here is a screen shot of the page right after a deploy!       Okay!  I know we could make a home page look much better!  However, I built this whole Integrated solution in less than a day with the caveat that the Green Master was already built!  So what am I saying?  Build you web parts, master pages, etc.  At the very end of the engagement build the pages.  The client will be very happy!  Here is the code for this solution Code

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  • How do I generate C# code from WADL files?

    - by Anders Sandvig
    I am looking for a code generator than can generate C# code to access RESTful web services described by WADL files in a way similar to how wadl2java works. Doing som searching I came across the rest-api-code-gen project on Google Code, but although the latest source does in fact support C#, the REST Describe & Compile demo site does not. (The C# button is there, but it's disabled.) I realize I could download the source and set up my own server with the latest version, but I would prefer not to, as what I need is a command line tool and not a web application with dependencies to Google Web Toolkit. I guess I could write my own a command line tool based on the same source code, but if it has already been done, or other tools can do the job, I'd rather avoid it. So, I'm wondering, are there any tools like that out there?

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  • Sending mail along with embedded image using javamail

    - by Raja D
    Hi All: I want to send mail along with embedded image. For that i have used the below code. Its not full code. Its a part of code Multipart multipart = new MimeMultipart("related"); // Create the message part BodyPart messageBodyPart; messageBodyPart = new MimeBodyPart(); messageBodyPart.setText(msgBody); // msgbody contains the contents of the html file messageBodyPart.setHeader("Content-Type", "text/html"); multipart.addBodyPart(messageBodyPart); //add file attachments DataSource source; File file = new File("D:/sample.jpeg"); if(file.exists()){ // add attachment messageBodyPart = new MimeBodyPart(); source = new FileDataSource(file); messageBodyPart.setDataHandler(new DataHandler(source)); messageBodyPart.setFileName(file.getName()); messageBodyPart.setHeader("Content-ID", "<BarcodeImage>"); messageBodyPart.setDisposition("inline"); multipart.addBodyPart(messageBodyPart); } // Put parts in message msg.setContent(multipart); Transport.send(msg); Problem i am facing is, i can get the mail but cant acle to see the image.. Its not get displaying in the mail. Below is my part of html file <img src=\"cid:BarcodeImage\" alt="Barcode" width="166" height="44" align="right" /> Please help me why the image not getting displayed in the mail and why it is not in the attachment??

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  • Is there a way to mark up code to tell ReSharper not to format it?

    - by adrianbanks
    I quite often use the ReSharper "Clean Up Code" command to format my code to our coding style before checking it into source control. This works well in general, but some bits of code are better formatted manually (eg. because of the indenting rules in ReSharper, things like chained linq methods or multi-line ternary operators have a strange indent that pushes them way to the right). Is there any way to mark up parts of a file to tell ReSharper not to format that area? I'm hoping for some kind of markup similar to how ReSharper suppresses other warnings/features. If not, is there some way of changing a combination of settings to get ReSharper to format the indenting correctly? EDIT: I have found this post from the ReSharper forums that says that generated code sections (as defined in the ReSharper options page) are ignored in code cleanup. Having tried it though, it doesn't seem to get ignored.

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  • Embedded Vimeo Video Callbacks

    - by Andrew
    This post is kind of a follow up to a post I made earlier in regards to HTML5 video callbacks. In that thread, I was given a great piece of code that would allow for the browser to be informed of when the video stops playing and then fire off an action (with jQuery). This is the code I'm currently using: $('video.normal').bind('ended', function(){ $(this).fadeOut().queue(function(){ $(this).siblings('.post-video').fadeIn(); $(this).dequeue(); }); }); Which basically fades the video out when it's completed and brings a poster frame of the video (or similar image) back into view. Well, the scope of the project has changed and now the client is asking for true full screen video and different size videos to be delivered based on user connection speed, something that's a little over my head and a lot over budget. So I've been researching and a Vimeo Plus player seems like a great alternative for visitors using a desktop browser (HD embeds, true full screen, and more). Thing is, I need that above code to continue working in some capacity or another, so does the embedded Vimeo player offer a similar callback that I can utilize? Or am I SOL here? Thanks in advance!

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  • How to properly rewrite ASSERT code to pass /analyze in msvc?

    - by Sorin Sbarnea
    Visual Studio added code analysis (/analyze) for C/C++ in order to help identify bad code. This is quite a nice feature but when you deal with and old project you may be overwhelmed by the number of warnings. Most of the problems are generating because the old code is doing some ASSERT at the beginning of the method or function. I think this is the ASSERT definition used in the code (from afx.h) #define ASSERT(f) DEBUG_ONLY((void) ((f) || !::AfxAssertFailedLine(THIS_FILE, __LINE__) || (AfxDebugBreak(), 0))) Example code: ASSERT(pBytes != NULL); *pBytes = 0; // <- warning C6011: Dereferencing NULL pointer 'pBytes' I'm looking for an easy and safe solution to solve these warnings that does not imply disabling these warnings. Did I mention that there are lots of occurrences in current codebase?

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  • Typical size of unit tests compared to test code

    - by Frank Schwieterman
    I'm curious what a reasonable / typical value is for the ratio of test code to production code when people are doing TDD. Looking at one component, I have 530 lines of test code for 130 lines of production code. Another component has 1000 lines of test code for 360 lines of production code. So the unit tests are requiring roughly 3x to 5x as much code. This is for Javascript code. I don't have much tested C# code handy, but I think for another project I was looking at 2x to 3x as much test code then production code. It would seem to me that the lower that value is, assuming the tests are sufficient, would reflect higher quality tests. Pure speculation, I just wonder what ratios other people see. I know lines of code is an loose metric, but since I code in the same style for both test and production (same spacing format, same ammount of comments, etc) the values are comparable.

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  • How can I reuse my javascript code between client and server?

    - by Chris Farmer
    I have some javascript code that includes an ANTLR-generated lexer and parser, and some associated syntax tree evaluation functionality. This code runs in the browser in my web app to support users who author code snippets which process scientific data. Now I'd like to do some additional background processing on the server using the same generated parser. I would prefer not to have to re-implement this stuff in C# and have multiple bits of code that did the exact same thing. Performance isn't as critical to me as eliminating duplication, since this is a background process. So, how can I call into my javascript code from C#? And how can I format my script so that it plays nicely with my .NET web app?

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  • C# Code Smells. What are the most common and how to fix them?

    - by Carlos Loth
    Hi, One thing I'd like to hear from you guys is what are the code smells that you see most often happen on C# code and how to fix them. I'm working on defining a code-review process for my team and I'd like to include a section with the most common C# code smells and a possible fix for each of them. I'd like the assistance of the community on that, so others can reuse this list for further reference. What are the most common smells you have seen on C# code? How did you fix them?

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  • Multiple CodeSnippet in an XML .snippet file

    - by Frinavale
    I'm attempting to supplement the help features for my code by providing other developers with code snippets. These produce skeletons of code which demonstrate how to use/call my classes or methods. I've created a .snippet file and have placed it in the "%Visual Studio Folder%\Code Snippets\Visual Basic\My Snippets" folder. I've used the Code Snippets Manager and ensured that it included this folder so that I can access the snippets. Everything works well when I have 1 CodeSnippet tag within the root CodeSnippets tag.... When I add more than one CodeSnippet tag to the file (each with their own title, and their own code example) I'm experiencing something strange. The first CodeSnippet I've added contains code for adding something to my system, the second contains code for editing something in my system, and the third deleting something from the system. When I use the code snippet by right clicking and selecting "Insert Code Snippet", only the first code snippet in the file shows up as an option. When I select it, the code in the first CodeSnippet is inserted....but so is the code within the other CodeSnippet tags. Do you have to have a separate XML .snippet file for each code snippet you want to make available? After reading through MSDN about creating Code Snippets I was under the impression that this could all be done within one file. It seems that I'm not understanding something very basic here and would love to find the answer but apparently Code Snippets are under used so finding the answer has proven to be a little trickier than I first thought it would be. Thanks, -Frinny

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  • Error handling in Rails Controller for adding embedded Mongoid documents to Model

    - by Dragonfly
    I have a Item model that has embedded documents. Currently, the following comments_controller code will add a comment to the item successfully. However, if pushing the comment document onto the comments array on item fails, I will not know this. #this does work, but i do not know if the push fails def create comment = Comment.new(:text => params[:text]) @item.comments << comment render :text => comment end I would like to have something like this, but @item.comments << comment does not return true or false: #this does not work def create comment = Comment.new(:text => params[:text]) if @item.comments << comment render :text => comment else render :text => 'oh no' end end Nor does it throw an exception when the document push fails: #this does not work def create begin comment = Comment.new(:text => params[:text]) @item.comments << comment render :text => comment rescue Exception => e render :text => 'oh no' end end Thanks!

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  • SWI-Prolog as an embedded application in VS2008 C++

    - by H.J. Miri
    I have a C++ application (prog.sln) which is my main program and I want to use Prolog as an embedded logic server (hanoi.pl) int main(int argc, char** argv) { putenv( "SWI_HOME_DIR=C:\\Program Files\\pl" ); argv[0] = "libpl.dll"; argv[1] = "-x"; argv[2] = "hanoi.pl"; argv[3] = NULL; PL_initialise(argc, argv); { fid_t fid = PL_open_foreign_frame(); predicate_t pred = PL_predicate( "hanoi", 1, "user" ); int rval = PL_call_predicate( NULL, PL_Q_NORMAL, pred, 3 ); qid_t qid = PL_open_query( NULL, PL_Q_NORMAL, pred, 3 ); while ( PL_next_solution(qid) ) return qid; PL_close_query(qid); PL_close_foreign_frame(fid); system("PAUSE"); } return 1; system("PAUSE"); } Here is my Prolog source code: :- use_module( library(shlib) ). hanoi( N ):- move( N, left, center, right ). move( 0, _, _, _ ):- !. move( N, A, B, C ):- M is N-1, move( M, A, C, B ), inform( A, B ), move( M, C, B, A ). inform( X, Y ):- write( 'move a disk from ' ), write( X ), write( ' to ' ), write( Y ), nl. I type at the command: plld -o hanoi prog.sln hanoi.pl But it doesn't compile. When I run my C++ app, it says: Undefined procedure: hanoi/1 What is missing/wrong in my code or at the prompt that prevents my C++ app from consulting Prolog? Appreciate any help/pointer.

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  • Is there an "embedded DBMS" to support multiple writer applications (processes) on the same db files

    - by Amir Moghimi
    I need to know if there is any embedded DBMS (preferably in Java and not necessarily relational) which supports multiple writer applications (processes) on the same set of db files. BerkeleyDB supports multiple readers but just one writer. I need multiple writers and multiple readers. UPDATE: It is not a multiple connection issue. I mean I do not need multiple connections to a running DBMS application (process) to write data. I need multiple DBMS applications (processes) to commit on the same storage files. HSQLDB, H2, JavaDB (Derby) and MongoDB do not support this feature. I think that there may be some File System limitations that prohibit this. If so, is there a File System that allows multiple writers on a single file? Use Case: The use case is a high-throughput clustered system that intends to store its high-volume business log entries into a SAN storage. Storing business logs in separate files for each server does not fit because query and indexing capabilities are needed on the whole biz logs. Because "a SAN typically is its own network of storage devices that are generally not accessible through the regular network by regular devices", I want to use SAN network bandwidth for logging while cluster LAN bandwidth is being used for other server to server and client to server communications.

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  • Static Data Structures on Embedded Devices (Android in particular)

    - by Mark
    I've started working on some Android applications and have a question regarding how people normally deal with situations where you have a static data set and have an application where that data is needed in memory as one of the standard java collections or as an array. In my current specific issue i have a spreadsheet with some pre-calculated data. It consists of ~100 rows and 3 columns. 1 Column is a string, 1 column is a float, 1 column is an integer. I need access to this data as an array in java. It seems like i could: 1) Encode in XML - This would be cpu intensive to decode in my experience. 2) build into SQLite database - seems like a lot of overhead for static access to data i only need array style access to in ram. 3) Build into binary blob and read in. (never done this in java, i miss void *) 4) Build a python script to take the CSV version of my data and spit out a java function that adds the values to my desired structure with hard coded values. 5) Store a string array via androids resource mechanism and compute the other 2 columns on application load. In my case the computation would require a lot of calls to Math.log, Math.pow and Math.floor which i'd rather not have to do for load time and battery usage reasons. I mostly work in low power embedded applications in C and as such #4 is what i'm used to doing in these situations. It just seems like it should be far easier to gain access to static data structures in java/android. Perhaps I'm just being too battery usage conscious and in my single case i imagine the answer is that it doesn't matter much, but if every application took that stance it could begin to matter. What approaches do people usually take in this situation? Anything I missed?

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