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  • object references an unsaved transient instance

    - by developer
    Hi, I have 2 tables, user and userprofile, both with almost identical fields. user table references userprofile table by primary key ID. My requirement is that on click of a button I need to dump user table record to userprofile table. Now for a particular user table, if there is a corresponding userprofile entry, I am successfully able to dump the data, but if there is no record in userprofile table then I need to create a new record by dumping all the data. My problem is that I am able to update the data when the record is present in userprofile table, but in the case wherein I have to create a new record I get the below error "object references an unsaved transient instance - save the transient instance before flushing". `<class name="User"> <id name="ID" type="Int32"> <generator class="native" /> </id> <many-to-one name="Pid" class="UserProfile" /> </class>` UserProfile is another table and Pid above references the Primary key ID of UserProfile table.

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  • Json.Net Issues: StackOverflowException is thrown when serialising circular dependent ISerializable object with ReferenceLoopHandling.Ignore

    - by keyr
    I have a legacy application that used binary serialisation to persist the data. Now we wanted to use Json.net 4.5 to serialise the data without much changes to the existing classes. Things were working nice till we hit a circular dependent class. Is there any workaround to solve this problem? Sample code as shown below [Serializable] class Department : ISerializable { public Employee Manager { get; set; } public string Name { get; set; } public Department() { } public Department( SerializationInfo info, StreamingContext context ) { Manager = ( Employee )info.GetValue( "Manager", typeof( Employee ) ); Name = ( string )info.GetValue( "Name", typeof( string ) ); } public void GetObjectData( SerializationInfo info, StreamingContext context ) { info.AddValue( "Manager", Manager ); info.AddValue( "Name", Name ); } } [Serializable] class Employee : ISerializable { [NonSerialized] //This does not work [XmlIgnore]//This does not work private Department mDepartment; public Department Department { get { return mDepartment; } set { mDepartment = value; } } public string Name { get; set; } public Employee() { } public Employee( SerializationInfo info, StreamingContext context ) { Department = ( Department )info.GetValue( "Department", typeof( Department ) ); Name = ( string )info.GetValue( "Name", typeof( string ) ); } public void GetObjectData( SerializationInfo info, StreamingContext context ) { info.AddValue( "Department", Department ); info.AddValue( "Name", Name ); } } And the test code Department department = new Department(); department.Name = "Dept1"; Employee emp1 = new Employee { Name = "Emp1", Department = department }; department.Manager = emp1; Employee emp2 = new Employee() { Name = "Emp2", Department = department }; IList<Employee> employees = new List<Employee>(); employees.Add( emp1 ); employees.Add( emp2 ); var memoryStream = new MemoryStream(); var formatter = new BinaryFormatter(); formatter.Serialize( memoryStream, employees ); memoryStream.Seek( 0, SeekOrigin.Begin ); IList<Employee> deserialisedEmployees = formatter.Deserialize( memoryStream ) as IList<Employee>; //Works nicely JsonSerializerSettings jsonSS= new JsonSerializerSettings(); jsonSS.TypeNameHandling = TypeNameHandling.Objects; jsonSS.TypeNameAssemblyFormat = FormatterAssemblyStyle.Full; jsonSS.Formatting = Formatting.Indented; jsonSS.ReferenceLoopHandling = ReferenceLoopHandling.Ignore; //This is not working!! //jsonSS.ReferenceLoopHandling = ReferenceLoopHandling.Serialize; //This is also not working!! jsonSS.PreserveReferencesHandling = PreserveReferencesHandling.All; string jsonAll = JsonConvert.SerializeObject( employees, jsonSS ); //Throws stackoverflow exception Edit1: The issue has been reported to Json (http://json.codeplex.com/workitem/23668)

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  • How list of references are represented in UML and does that break any DDD rules ?

    - by Rushino
    Hello, How a list of references are represented in UML ? Example : a Calendar contain a list of phases which contain a list of sequences which contain a list of assignations Calendar is root because phases and sequences and assignations only work in context of a calendar. But assignations must hold multiple references to groups of students. (Must work two sides) Would like to know if its possible to hold multiple references of an aggregate root (groups) inside another aggregate root (calendar) member ? Also how a list of references are represented in UML ? it is a simple relation ? Also does this break any rules in DDD domain ? Thanks.

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  • Merging bibtex reference with MS Word?

    - by Akhil
    I have a paper submission in about 12 hours. I have written references in a separate .bib file in bibtex format. Now please tell how to merge the references with my paper written in MS word in the simplest/ easiest possible manner. I am looking for some automatic tool that does this. I have never used bibtex before. In fact I came to know about bibtex few hours ago only.

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  • merging bibtex refernce with MS word

    - by Akhil
    I have a paper submission in about 12 hours. I have written references in a separate .bib file in bibtex format. Now please tell how to merge the references with my paper written in MS word in the simplest/ easiest possible manner. I am looking for some automatic tool that does this. I have never used bibtex before. In fact I came to know about bibtex few hours ago only.

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  • C#/.NET Project - Am I setting things up correctly?

    - by JustLooking
    1st solution located: \Common\Controls\Controls.sln and its project: \Common\Controls\Common.Controls\Common.Controls.csproj Description: This is a library that contains this class: public abstract class OurUserControl : UserControl { // Variables and other getters/setters common to our UserControls } 2nd solution located: \AControl\AControl.sln and its project: \AControl\AControl\AControl.csproj Description: Of the many forms/classes, it will contain this class: using Common.Controls; namespace AControl { public partial class AControl : OurUserControl { // The implementation } } A note about adding references (not sure if this is relevant): When I add references (for projects I create), using the names above: 1. I add Common.Controls.csproj to AControl.sln 2. In AControl.sln I turn off the build of Common.Controls.csproj 3. I add the reference to Common.Controls (by project) to AControl.csproj. This is the (easiest) way I know how to get Debug versions to match Debug References, and Release versions to match Release References. Now, here is where the issue lies (the 3rd solution/project that actually utilizes the UserControl): 3rd solution located: \MainProj\MainProj.sln and its project: \MainProj\MainProj\MainProj.csproj Description: Here's a sample function in one of the classes: private void TestMethod<T>() where T : Common.Controls.OurUserControl, new() { T TheObject = new T(); TheObject.OneOfTheSetters = something; TheObject.AnotherOfTheSetters = something_else; // Do stuff with the object } We might call this function like so: private void AnotherMethod() { TestMethod<AControl.AControl>(); } This builds, runs, and works. No problem. The odd thing is after I close the project/solution and re-open it, I have red squigglies everywhere. I bring up my error list and I see tons of errors (anything that deals with AControl will be noted as an error). I'll see errors such as: The type 'AControl.AControl' cannot be used as type parameter 'T' in the generic type or method 'MainProj.MainClass.TestMethod()'. There is no implicit reference conversion from 'AControl.AControl' to 'Common.Controls.OurUserControl'. or inside the actual method (the properties located in the abstract class): 'AControl.AControl' does not contain a definition for 'OneOfTheSetters' and no extension method 'OneOfTheSetters' accepting a first argument of type 'AControl.AControl' could be found (are you missing a using directive or an assembly reference?) Meanwhile, I can still build and run the project (then the red squigglies go away until I re-open the project, or close/re-open the file). It seems to me that I might be setting up the projects incorrectly. Thoughts?

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  • How to use unset() for this Linear Linked List in PHP

    - by Peter
    I'm writing a simple linear linked list implementation in PHP. This is basically just for practice... part of a Project Euler problem. I'm not sure if I should be using unset() to help in garbage collection in order to avoid memory leaks. Should I include an unset() for head and temp in the destructor of LLL? I understand that I'll use unset() to delete nodes when I want, but is unset() necessary for general clean up at any point? Is the memory map freed once the script terminates even if you don't use unset()? I saw this SO question, but I'm still a little unclear. Is the answer that you simply don't have to use unset() to avoid any sort of memory leaks associated with creating references? I'm using PHP 5.. btw. Unsetting references in PHP PHP references tutorial Here is the code - I'm creating references when I create $temp and $this-head at certain points in the LLL class: class Node { public $data; public $next; } class LLL { // The first node private $head; public function __construct() { $this->head = NULL; } public function insertFirst($data) { if (!$this->head) { // Create the head $this->head = new Node; $temp =& $this->head; $temp->data = $data; $temp->next = NULL; } else { // Add a node, and make it the new head. $temp = new Node; $temp->next = $this->head; $temp->data = $data; $this->head =& $temp; } } public function showAll() { echo "The linear linked list:<br/>&nbsp;&nbsp;"; if ($this->head) { $temp =& $this->head; do { echo $temp->data . " "; } while ($temp =& $temp->next); } else { echo "is empty."; } echo "<br/>"; } } Thanks!

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  • Crop circular or elliptical image from original UIImage

    - by vikas ojha
    I am working on openCV for detecting the face .I want face to get cropped once its detected.Till now I got the face and have marked the rect/ellipse around it on iPhone. Please help me out in cropping the face in circular/elliptical pattern (UIImage *) opencvFaceDetect:(UIImage *)originalImage { cvSetErrMode(CV_ErrModeParent); IplImage *image = [self CreateIplImageFromUIImage:originalImage]; // Scaling down /* Creates IPL image (header and data) ----------------cvCreateImage CVAPI(IplImage*) cvCreateImage( CvSize size, int depth, int channels ); */ IplImage *small_image = cvCreateImage(cvSize(image->width/2,image->height/2), IPL_DEPTH_8U, 3); /*SMOOTHES DOWN THYE GUASSIAN SURFACE--------:cvPyrDown*/ cvPyrDown(image, small_image, CV_GAUSSIAN_5x5); int scale = 2; // Load XML NSString *path = [[NSBundle mainBundle] pathForResource:@"haarcascade_frontalface_default" ofType:@"xml"]; CvHaarClassifierCascade* cascade = (CvHaarClassifierCascade*)cvLoad([path cStringUsingEncoding:NSASCIIStringEncoding], NULL, NULL, NULL); // Check whether the cascade has loaded successfully. Else report and error and quit if( !cascade ) { NSLog(@"ERROR: Could not load classifier cascade\n"); //return; } //Allocate the Memory storage CvMemStorage* storage = cvCreateMemStorage(0); // Clear the memory storage which was used before cvClearMemStorage( storage ); CGColorSpaceRef colorSpace; CGContextRef contextRef; CGRect face_rect; // Find whether the cascade is loaded, to find the faces. If yes, then: if( cascade ) { CvSeq* faces = cvHaarDetectObjects(small_image, cascade, storage, 1.1f, 3, 0, cvSize(20, 20)); cvReleaseImage(&small_image); // Create canvas to show the results CGImageRef imageRef = originalImage.CGImage; colorSpace = CGColorSpaceCreateDeviceRGB(); contextRef = CGBitmapContextCreate(NULL, originalImage.size.width, originalImage.size.height, 8, originalImage.size.width * 4, colorSpace, kCGImageAlphaPremultipliedLast|kCGBitmapByteOrderDefault); //VIKAS CGContextDrawImage(contextRef, CGRectMake(0, 0, originalImage.size.width, originalImage.size.height), imageRef); CGContextSetLineWidth(contextRef, 4); CGContextSetRGBStrokeColor(contextRef, 1.0, 1.0, 1.0, 0.5); // Draw results on the iamge:Draw all components of face in the form of small rectangles // Loop the number of faces found. for(int i = 0; i < faces->total; i++) { NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init]; // Calc the rect of faces // Create a new rectangle for drawing the face CvRect cvrect = *(CvRect*)cvGetSeqElem(faces, i); // CGRect face_rect = CGContextConvertRectToDeviceSpace(contextRef, // CGRectMake(cvrect.x * scale, cvrect.y * scale, cvrect.width * scale, cvrect.height * scale)); face_rect = CGContextConvertRectToDeviceSpace(contextRef, CGRectMake(cvrect.x*scale, cvrect.y , cvrect.width*scale , cvrect.height*scale*1.25 )); facedetectapp=(FaceDetectAppDelegate *)[[UIApplication sharedApplication]delegate]; facedetectapp.grabcropcoordrect=face_rect; NSLog(@" FACE off %f %f %f %f",facedetectapp.grabcropcoordrect.origin.x,facedetectapp.grabcropcoordrect.origin.y,facedetectapp.grabcropcoordrect.size.width,facedetectapp.grabcropcoordrect.size.height); CGContextStrokeRect(contextRef, face_rect); //CGContextFillEllipseInRect(contextRef,face_rect); CGContextStrokeEllipseInRect(contextRef,face_rect); [pool release]; } } CGImageRef imageRef = CGImageCreateWithImageInRect([originalImage CGImage],face_rect); UIImage *returnImage = [UIImage imageWithCGImage:imageRef]; CGImageRelease(imageRef); CGContextRelease(contextRef); CGColorSpaceRelease(colorSpace); cvReleaseMemStorage(&storage); cvReleaseHaarClassifierCascade(&cascade); return returnImage; } } Thanks Vikas

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  • Test for external undefined references in Linux

    - by Charles
    Is there a built in linux utility that I can use to test a newly compiled shared library for external undefined references? Gcc seems to be intelligent enough to check for undefined symbols in my own binary, but if the symbol is a reference to another library gcc does not check at link time. Instead I only get the message when I try to link to my new library from another program. It seems a little silly to get undefined reference messages in a library when I am compiling a different project so I want to know if I can do a check on all references internal and external when I build the library not when I link to it. Example error: make -C UnitTests debug make[1]: Entering directory `~/projects/Foo/UnitTests` g++ [ tons of objects ] -L../libbar/bin -lbar -o UnitTests libbar.so: undefined reference to `DoSomethingFromAnotherLibrary` collect2: ld returned 1 exit status make[1]: *** [~/projects/Foo/UnitTests] Error 1

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  • Test for undefined references in Linux

    - by Charles
    Is there a built in linux utility that I can use to test a newly compiled shared library for external undefined references? Gcc seems to be intelligent enough to check for undefined symbols in my own binary, but if the symbol is a reference to another library gcc does not check at link time. Instead I only get the message when I try to link to my new library from another program. It seems a little silly to get undefined reference messages in a library when I am compiling a different project so I want to know if I can do a check on all references internal and external when I build the library not when I link to it. Example error: make -C UnitTests debug make[1]: Entering directory `~/projects/Foo/UnitTests` g++ [ tons of objects ] -L../libbar/bin -lbar -o UnitTests libbar.so: undefined reference to `DoSomethingFromAnotherLibrary` collect2: ld returned 1 exit status make[1]: *** [~/projects/Foo/UnitTests] Error 1

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  • asp.net mvc script and style references

    - by tom
    I'm trying to include script and style references that will not break on deployment, however I can not even get the references to work locally. I have tried using Url.Content() and MVCContrib's <%=Html.ScriptInclude("")%>. My scripts are in a Scripts folder on the root of the site; my styles are in the usual Content/css/ folder. The scripts render like this: <script type="text/javascript" src="/Scripts/MicrosoftAjax.debug.js" ></script> This will not work in a view page in the Views folder. What am I doing wrong and what is the best way to handle this? I would have thought Url.Content() would at least work for styles but used in my master page, the link rendered <link href="/Content/css/Site.css rel="stylesheet" type="text/css" /> This does not work, because the Master Page is in a Shared folder, so what is really the way forward with this?

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  • Automatically insert Cell References from one Sheet into other Sheet in OOO Calc

    - by user123456
    I have a spreadsheet in Open Office 3.0 Calc. The spreadsheets consist of the first sheet and an arbitrary number of additional sheets, each collecting data for a specific month. The Month sheets have an identical structure. The first sheet is supposed to provide an overview to the most important numbers in the month sheets. What I would like to do is this: Whenever I add a Month sheet, I want it to appear automatically in the Overview sheet with the structure given below. So, for each Month sheet, copy or reference some of the cells into the Overview sheet: {Referenced Sheet Name} | Fixed Header1 | Fixed Header2 | Fixed Header3 Fixed Label 1 | {CellRef 1} | {CellRef 2} | {CellRef 3} Fixed Label 2 | {CellRef 4} | {CellRef 5} | {CellRef 6} I know how do to this for just one sheet by hand, but I have no clue how to make OOO do this automatically for me. Is it possible at all? Any help appreciated. Thanks.

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  • Automatically insert cell references from one sheet into other in Calc

    - by user123456
    I have spreadsheets in OpenOffice.org Calc that consist of the first sheet and an arbitrary number of additional sheets, each collecting data for a specific month. The Month sheets have an identical structure. The first sheet is supposed to provide an overview to the most important numbers in the month sheets. Whenever I add a Month sheet, I want it to appear automatically in the Overview sheet with the structure given below. So, for each Month sheet, copy or reference some of the cells into the Overview sheet: {Referenced Sheet Name} | Fixed Header1 | Fixed Header2 | Fixed Header3 Fixed Label 1 | {CellRef 1} | {CellRef 2} | {CellRef 3} Fixed Label 2 | {CellRef 4} | {CellRef 5} | {CellRef 6} I know how do to this for just one sheet by hand, but I have no clue how to make Calc do this automatically for me. Is it possible at all? Any help appreciated.

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  • MS Word TOC that references # pages rather than page number

    - by buttonsrtoys
    We frequently need to write specifications in Word which require a TOC that refers to the total number of pages in a section, rather than the page number. E.g., Section No. Pages 01010 Summary of Work..............5 01025 Prices.......................2 01400 Quality Control..............1 01700 Contract Close Out...........2 A wrinkle is that each section is a separate file. To date, we've been writing or TOC by hand, which has introduced every error imaginable. Is there an MS feature that populates a TOC with page totals? If not, I've done a little VB in Office, so wouldn't be opposed to that route as need be, as long as it was usable by our low tech users. Related question - all the section files are in the same folder. It would be nice if the TOC loaded every file in a folder, rather than having to specify each one. Is this a feature of Word or would this require VB? We tried a master document with links to subdocuments, but since the number of section files ebbs and flows with each project, the approach required too much maintenance for our Wordophobes.

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  • How to avoid circular dependencies between Player and World?

    - by futlib
    I'm working on a 2D game where you can move up, down, left and right. I have essentially two game logic objects: Player: Has a position relative to the world World: Draws the map and the player So far, World depends on Player (i.e. has a reference to it), needing its position to figure out where to draw the player character, and which portion of the map to draw. Now I want to add collision detection to make it impossible for the player to move through walls. The simplest way I can think of is to have the Player ask the World if the intended movement is possible. But that would introduce a circular dependency between Player and World (i.e. each holds a reference to the other), which seems worth avoiding. The only way I came up with is to have the World move the Player, but I find that somewhat unintuitive. What is my best option? Or is avoiding a circular dependency not worth it?

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  • x86 opcode alignment references and guidelines

    - by mrjoltcola
    I'm generating some opcodes dynamically in a JIT compiler and I'm looking for guidelines for opcode alignment. 1) I've read comments that briefly "recommend" alignment by adding nops after calls 2) I've also read about using nop for optimizing sequences for parallelism. 3) I've read that alignment of ops is good for "cache" performance Usually these comments don't give any supporting references. Its one thing to read a blog or a comment that says, "its a good idea to do such and such", but its another to actually write a compiler that implements specific op sequences and realize most material online, especially blogs, are not useful for practical application. So I'm a believer in finding things out myself (disassembly, etc. to see what real world apps do). This is one case where I need some outside info. I notice compilers will usually start an odd byte instruction immediately after whatever previous instruction sequence there was. So the compiler is not taking any special care in most cases. I see "nop" here or there, but usually it seems nop is used sparingly, if at all. How critical is opcode alignment? Can you provide references for cases that I can actually use for implementation? Thanks.

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  • Alternatives to storing Moose object using Apache::Session with CODE references

    - by Hartmut Behrens
    I have a Moose class that i would like to store using Apache::Session::File. However, Apache::Session::File by default will not store it and instead i get the error message: (in cleanup) Can't store CODE items at blib\lib\Storable.pm (autosplit into blib\lib\auto\Storable\_freeze.al)... This problem can be circumvented by setting $Storable::Deparse = 1; $Storable::Eval = 1; in order to allow CODE references to be serialized. The offending method in the Moose class is listed below, which retrieves a column from a mysql database: sub _build_cell_generic { my ($self,$col) = @_; my $sth = $self->call_dbh('prepare','select '.$col.' from '.$self->TABLE.' where CI = ? and LAC = ? and IMPORTDATE = ?'); $sth->execute($self->CI,$self->LAC,$self->IMPORTDATE); my $val = $sth->fetchrow_array; $sth->finish; return defined $val ? $val : undef; } So presumably the dbh object (isa DBIx::Connector) contains CODE references. Is there a better alternative in order to allow serialization of this Moose class than setting $Storable::Deparse and $Storable::Eval ?

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  • How to properly use references with variadic templates

    - by Hippicoder
    I have something like the following code: template<typename T1, typename T2, typename T3> void inc(T1& t1, T2& t2, T3& t3) { ++t1; ++t2; ++t3; } template<typename T1, typename T2> void inc(T1& t1, T2& t2) { ++t1; ++t2; } template<typename T1> void inc(T1& t1) { ++t1; } I'd like to reimplement it using the proposed variadic templates from the upcoming standard. However all the examples I've seen so far online seem to be printf like examples, the difference here seems to be the use of references. I've come up with the following: template<typename T> void inc(T&& t) { ++t; } template<typename T,typename ... Args> void inc(T&& t, Args&& ... args) { ++t inc(args...); } What I'd like to know is: Should I be using r-values instead of references? Possible hints or clues as to how to accomplish what I want correctly. What guarantees does the new proposed standard provide wrt the issue of the recursive function calls, is there some indication that the above variadic version will be as optimal as the original? (should I add inline or some-such?)

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  • C++0x rvalue references and temporaries

    - by Doug
    (I asked a variation of this question on comp.std.c++ but didn't get an answer.) Why does the call to f(arg) in this code call the const ref overload of f? void f(const std::string &); //less efficient void f(std::string &&); //more efficient void g(const char * arg) { f(arg); } My intuition says that the f(string &&) overload should be chosen, because arg needs to be converted to a temporary no matter what, and the temporary matches the rvalue reference better than the lvalue reference. This is not what happens in GCC and MSVC. In at least G++ and MSVC, any lvalue does not bind to an rvalue reference argument, even if there is an intermediate temporary created. Indeed, if the const ref overload isn't present, the compilers diagnose an error. However, writing f(arg + 0) or f(std::string(arg)) does choose the rvalue reference overload as you would expect. From my reading of the C++0x standard, it seems like the implicit conversion of a const char * to a string should be considered when considering if f(string &&) is viable, just as when passing a const lvalue ref arguments. Section 13.3 (overload resolution) doesn't differentiate between rvalue refs and const references in too many places. Also, it seems that the rule that prevents lvalues from binding to rvalue references (13.3.3.1.4/3) shouldn't apply if there's an intermediate temporary - after all, it's perfectly safe to move from the temporary. Is this: Me misreading/misunderstand the standard, where the implemented behavior is the intended behavior, and there's some good reason why my example should behave the way it does? A mistake that the compiler vendors have somehow all made? Or a mistake based on common implementation strategies? Or a mistake in e.g. GCC (where this lvalue/rvalue reference binding rule was first implemented), that was copied by other vendors? A defect in the standard, or an unintended consequence, or something that should be clarified?

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  • Displaying Flex Object References

    - by Pie21
    I have a bit of a memory leak issue in my Flex application, and the short version of my question is: is there any way (in AcitonScript 3) to find all live references to a given object? What I have is a number of views with presentation models behind each of them (using Swiz). The views of interest are children of a TabNavigator, so when I close the tab, the view is removed from the stage. When the view is removed from the stage, Swiz sets the model reference in the view to null, as it should. I also removeAllChildren() from the view. However when profiling the application, when I do this and run a GC, neither the view nor the presentation model are freed (though both set their references to each other to null). One model object used by the view (not a presenter, though) IS freed, so it's not completely broken. I've only just started profiling today (firmly believing in not optimising too early), so I imagine there's some kind of reference floating around somewhere, but I can't see where, and what would be super helpful would be the ability to debug and see a list of objects that reference the target object. Is this at all possible, and if not natively, is there some light-weight way to code this into future apps for debugging purposes? Cheers.

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  • Django: Storing ordered, arbitrary references

    - by Sarah
    I'm new to Django, and I'm not sure what I want is possible: I have a number of items that I want each AppUser (extended User model) to be able to reference. That is, given an AppUser, I want to be able to extract its list of items in the way that AppUser has chosen to order them. In general, these items would actually be references to something else in the database, and this led me to one possible solution: Store the keys for the given objects in a CommaSeparatedIntegerField in AppUser. This way, a user could have stored {7, 3, 232, 42, 1} in their items field and both the references and their preferred order would be stored. However, this feels hacky. Since most db backends store CommaSeparatedIntegerField as a VARCHAR internally, the user is not only limited by a number of objects, but also the number of digits in their chosen items. Eg. "you may store 10 items if you choose items with itemID < 10, but only 5 items if 10 < itemID < 100". Is there a better way to do this?

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  • Perl help dereferencing a reference to an array of hash references, containing record set data

    - by user1724150
    I'm using the a Amazon Perl module that returns a reference to an array of hash references as $record_sets, containing record set data and I'm having a hard time dereferencing it. I can print the data using data dumper but I need to be able to manipulate the data. Below is the documentation provided for the module Thanks In Advance: #list_resource_record_sets #Lists resource record sets for a hosted zone. #Called in scalar context: $record_sets = $r53->list_resource_record_sets(zone_id => '123ZONEID'); #Returns: A reference to an array of hash references, containing record set data. Example: $record_sets = [ { name => 'example.com.', type => 'MX' ttl => 86400, records => [ '10 mail.example.com' ] }, { name => 'example.com.', type => 'NS', ttl => 172800, records => [ 'ns-001.awsdns-01.net.', 'ns-002.awsdns-02.net.', 'ns-003.awsdns-03.net.', 'ns-004.awsdns-04.net.' ]

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  • weakref list in python

    - by Dan
    I'm in need of a list of weak references that deletes items when they die. Currently the only way I have of doing this is to keep flushing the list (removing dead references manually). I'm aware there's a WeakKeyDictionary and a WeakValueDictionary, but I'm really after a WeakList, is there a way of doing this? Here's an example: import weakref class A(object): def __init__(self): pass class B(object): def __init__(self): self._references = [] def addReference(self, obj): self._references.append(weakref.ref(obj)) def flush(self): toRemove = [] for ref in self._references: if ref() is None: toRemove.append(ref) for item in toRemove: self._references.remove(item) b = B() a1 = A() b.addReference(a1) a2 = A() b.addReference(a2) del a1 b.flush() del a2 b.flush()

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