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  • how to do validations when composing object of a class in other class ?

    - by haansi
    Hi, I have an IPAddress class which has one property named ip and in its setter I am validating data coming and if data is invalid it throws an error. (Its code is as the following): private string ip; public string IP { get { return ip; } set { string PartsOfIP = value.Split('.'); if (PartsOfIP.Length == 4) { foreach (string part in PartsOfIP) { int a = 0; bool result = int.TryParse(part, out a); if (result != true) { throw new Exception("Invalid IP"); } else { ip = value; } } } else { throw new Exception("Invalid IP"); } } In User Class I want to compose an object of IPAddress class. I am doing validations for properties of User in User class and validations of Ip in IPAddress class. My question is how I will compose IPAddress object in UserClass and what will be syntax for this ? If I again mention get and set here with IPAddress object in User class will my earlier mentioned (in IPAddress class) getter and setter work ? plz advice me in details thanks

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  • Need advice on C++ coding pattern

    - by Kotti
    Hi! I have a working prototype of a game engine and right now I'm doing some refactoring. What I'm asking for is your opinion on usage of the following C++ coding patterns. I have implemented some trivial algorithms for collision detection and they are implemented the following way: Not shown here - class constructor is made private and using algorithms looks like Algorithm::HandleInnerCollision(...) struct Algorithm { // Private routines static bool is_inside(Point& p, Object& object) { // (...) } public: /** * Handle collision where the moving object should be always * located inside the static object * * @param MovingObject & mobject * @param const StaticObject & sobject * @return void * @see */ static void HandleInnerCollision(MovingObject& mobject, const StaticObject& sobject) { // (...) } So, my question is - somebody advised me to do it "the C++" way - so that all functions are wrapped in a namespace, but not in a class. Is there some good way to preserve privating if I will wrap them into a namespace as adviced? What I want to have is a simple interface and ability to call functions as Algorithm::HandleInnerCollision(...) while not polluting the namespace with other functions such as is_inside(...) Of, if you can advise any alternative design pattern for such kind of logics, I would really appreciate that...

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  • Help: List contents of iPhone application bundle subpath??

    - by bluepill
    Hi, I am trying to get a listing of the directories contained within a subpath of my application bundle. I've done some searching and this is what I have come up with - (void) contents { NSArray *contents = [[NSBundle mainBundle] pathsForResourcesOfType:nil inDirectory:@"DataDir"]; if (contents = nil) { NSLog(@"Failed: path doesn't exist or error!"); } else { NSString *bundlePathName = [[NSBundle mainBundle] bundlePath]; NSString *dataPathName = [bundlePathName stringByAppendingPathComponent: @"DataDir"]; NSFileManager *fileManager = [NSFileManager defaultManager]; NSMutableArray *directories = [[NSMutableArray alloc] init]; for (NSString *entityName in contents) { NSString *fullEntityName = [dataPathName stringByAppendingPathComponent:entityName]; NSLog(@"entity = %@", fullEntityName); BOOL isDir = NO; [fileManager fileExistsAtPath:fullEntityName isDirectory:(&isDir)]; if (isDir) { [directories addObject:fullEntityName]; NSLog(@" is a directory"); } else { NSLog(@" is not a directory"); } } NSLog(@"Directories = %@", directories); [directories release]; } } As you can see I am trying to get a listing of directories in the app bundle's DataDir subpath. The problem is that I get no strings in my contents NSArray. note: - I am using the simulator - When I manually look in the .app file I can see DataDir and the contents therein - The contents of DataDir are png files and directories that contain png files - The application logic needs to discover the contents of DataDir at runtime - I have also tried using NSArray *contents = [fileManager contentsOfDirectoryAtPath:DataDirPathName error:nil]; and I still get no entries in my contents array Any suggestions/alternative approaches? Thanks.

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  • Problem in calling a function from different class using protocols-iphone

    - by Muniraj
    I use cocos2d for my game. In which I play a movie and have a separate overlay view for controls.The touches are detected in the overlay view. Now when the touches are detected the function in the game code has to be invoked. But the function is not detected and there is no error. I dont know what has gone wrong. Someone please help me. The code are as follows The protocol part is @protocol Protocol @required -(void) transition1:(id) sender; @end The function which is to be invoked in the game code is (void) transition1:(id) sender { [[Director sharedDirector] replaceScene: [ [Scene node] addChild: [Layer4 node] z:0] ]; } The code in the overlay view in MovieOverlayViewController.h import "Protocol.h" @interface MovieOverlayViewController : UIViewController { UIImageView *overlay; NSObject <Protocol> *transfer; } @end The code in the overlay view in MovieOverlayViewController.m @implementation MovieOverlayViewController (id)init { if ((self = [super init])) self.view = [[[UIView alloc] initWithFrame:[[UIScreen mainScreen] applicationFrame]] autorelease]; return self; } -(void) viewWillAppear:(BOOL)animated { overlay = [[[UIImageView alloc] initWithImage:[UIImage imageNamed:@"overlay.png"]] autorelease]; [self.view addSubview:overlay]; } (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event { UITouch *touch = [touches anyObject]; CGPoint point = [touch locationInView:self.view]; NSLog(@"pointx: %f pointy:%f", point.x, point.y); if (CGRectContainsPoint(CGRectMake(1, 440, 106, 40), point)) { // the function is called here [transfer transition1: nil]; } else if (CGRectContainsPoint(CGRectMake(107, 440, 106, 40), point)) NSLog(@"tab 2 touched"); } (void)dealloc { [overlay release]; [super dealloc]; } @end

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  • Execute SSH commands on Cisco router. Codeigniter SSH library

    - by jomajo
    I have a little problem. I'm using Codeigniter with SSH library written by Shuky (https://bitbucket.org/quicktips/codeigniter-ssh2-library/src/a444968345ba/SSH.php -- You can see the code by following this link). Everything related with SSH works fine with other devices, but when I try to use this library and execute commands on Cisco devices, nothing happens (commands are not executed). I know that the connection is successful, but I can't execute any commands. When I try to run and execute comands through SSH on Cisco devices I get this error: A PHP Error was encountered Severity: Warning Message: stream_set_blocking() expects parameter 1 to be resource, boolean given Filename: libraries/SSH.php Line Number: 128 A PHP Error was encountered Severity: Warning Message: fread() expects parameter 1 to be resource, boolean given Filename: libraries/SSH.php Line Number: 129 In the library these lines look like this: /** * Get stream data * * @access privte * @return bool */ function _get_stream_data($stream) { stream_set_blocking( $stream, true ); while( $buf = fread($stream,4096) ) { $this->data .= $buf.'~'; } return TRUE; } line 128 - stream_set_blocking( $stream, true ); line 129 - while( $buf = fread($stream,4096) ) { Maybe you guys know where the problem is? Thank you for your time and your answers!

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  • How to create a progress bar while downloading a file using the windows API?

    - by Jorge Chayan
    i'm working on an application in MS Visual C++ using Windows API that must download a file and place it in a folder. I have already implemented the download using URLDownloadToFile function, but i want to create a PROGRESS_CLASS progress bar with marquee style while the file is being downloaded, but it doesn't seems to get animated in the process. This is the function I use for downloading: BOOL SOXDownload() { HRESULT hRez = URLDownloadToFile(NULL, "url","C:\\sox.zip", 0, NULL); if (hRez == E_OUTOFMEMORY ) { MessageBox(hWnd, "Out of memory Error","", MB_OK); return FALSE; } if (hRez != S_OK) { MessageBox(hWnd, "Error downloading sox.", "Error!", MB_ICONERROR | MB_SYSTEMMODAL); return FALSE; } if (hRez == S_OK) { BSTR file = SysAllocString(L"C:\\sox.zip"); BSTR folder = SysAllocString(L"C:\\"); Unzip2Folder(file, folder); ::MessageBoxA(hWnd, "Sox Binaries downloaded succesfully", "Success", MB_OK); } return TRUE; } Later I call inside WM_CREATE (in my main window's message processor): if (!fileExists("C:\\SOX\\SOX.exe")) { components[7] = CreateWindowEx(0, PROGRESS_CLASS, NULL, WS_VISIBLE | PBS_MARQUEE, GetSystemMetrics(SM_CXSCREEN) / 2 - 80, GetSystemMetrics(SM_CYSCREEN) / 2 + 25, 200, 50, hWnd, NULL, NULL, NULL); SetWindowText(components[7], "Downloading SoX"); SendMessage(components[7], PBM_SETRANGE, 0, (LPARAM) MAKELPARAM(0, 50)); SendMessage(components[7], PBM_SETMARQUEE, TRUE, MAKELPARAM( 0, 50)); SOXDownload(); SendMessage(components[7], WM_CLOSE, NULL, NULL); } And as I want, I get a tiny progress bar... But it's not animated, and when I place the cursor over the bar, the cursor indicates that the program is busy downloading the file. When the download is complete, the window closes as i requested: SendMessage(components[7], WM_CLOSE, NULL, NULL); So the question is how can I make the bar move while downloading the file? Considering that i want it done with marquee style for simplicity. Thanks in advance.

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  • Cocoa memory management - object going nil on me

    - by SirRatty
    Hi all, Mac OS X 10.6, Cocoa project, with retain/release gc I've got a function which: iterates over a specific directory, scans it for subfolders (included nested ones), builds an NSMutableArray of strings (one string per found subfolder path), and returns that array. e.g. (error handling removed for brevity). NSMutableArray * ListAllSubFoldersForFolderPath(NSString *folderPath) { NSMutableArray *a = [NSMutableArray arrayWithCapacity:100]; NSString *itemName = nil; NSFileManager *fm = [NSFileManager defaultManager]; NSDirectoryEnumerator *e = [fm enumeratorAtPath:folderPath]; while (itemName = [e nextObject]) { NSString *fullPath = [folderPath stringByAppendingPathComponent:itemName]; BOOL isDirectory; if ([fm fileExistsAtPath:fullPath isDirectory:&isDirectory]) { if (isDirectory is_eq YES) { [a addObject: fullPath]; } } } return a; } The calling function takes the array just once per session, keeps it around for later processing: static NSMutableArray *gFolderPaths = nil; ... gFolderPaths = ListAllSubFoldersForFolderPath(myPath); [gFolderPaths retain]; All appears good at this stage. [gFolderPaths count] returns the correct number of paths found, and [gFolderPaths description] prints out all the correct path names. The problem: When I go to use gFolderPaths later (say, the next run through my event loop) my assertion code (and gdb in Xcode) tells me that it is nil. I am not modifying gFolderPaths in any way after that initial grab, so I am presuming that my memory management is screwed and that gFolderPaths is being released by the runtime. My assumptions/presumptions I do not have to retain each string as I add it to the mutable array because that is done automatically, but I do have to retain the the array once it is handed over to me from the function, because I won't be using it immediately. Is this correct? Any help is appreciated.

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  • Will C++0x support __stdcall or extern "C" capture-nothing lambdas?

    - by Daniel Trebbien
    Yesterday I was thinking about whether it would be possible to use the convenience of C++0x lambda functions to write callbacks for Windows API functions. For example, what if I wanted to use a lambda as an EnumChildProc with EnumChildWindows? Something like: EnumChildWindows(hTrayWnd, CALLBACK [](HWND hWnd, LPARAM lParam) { // ... return static_cast<BOOL>(TRUE); // continue enumerating }, reinterpret_cast<LPARAM>(&myData)); Another use would be to write extern "C" callbacks for C routines. E.g.: my_class *pRes = static_cast<my_class*>(bsearch(&key, myClassObjectsArr, myClassObjectsArr_size, sizeof(my_class), extern "C" [](const void *pV1, const void *pV2) { const my_class& o1 = *static_cast<const my_class*>(pV1); const my_class& o2 = *static_cast<const my_class*>(pV2); int res; // ... return res; })); Is this possible? I can understand that lambdas that capture variables will never be compatible with C, but it at least seems possible to me that capture-nothing lambdas can be compatible.

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  • Print UITableView that has content off screen?

    - by Daniel
    Hi I have an iOS app that has the ability to print a UITableView. However, only th part of the tableview that is shown is printed. Is there a way to print the whole tableview, even if it has not been drawn yet? Here is the code I am using to print: UIGraphicsBeginImageContext(self.mainTableView.contentSize); [self.mainTableView.layer renderInContext:UIGraphicsGetCurrentContext()]; UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); UIPrintInteractionController *printer = [UIPrintInteractionController sharedPrintController]; printer.printingItem = viewImage; UIPrintInfo *info = [UIPrintInfo printInfo]; printer.printInfo = info; UIPrintInteractionCompletionHandler completionHandler = ^(UIPrintInteractionController *pic, BOOL completed, NSError *error) { if (!completed && error) NSLog(@"FAILED! due to error in domain %@ with error code %u: %@", error.domain, error.code, [error localizedDescription]); }; UIButton * printButton = (UIButton *)sender; if(UIUserInterfaceIdiomPad == [[UIDevice currentDevice] userInterfaceIdiom]){ [printer presentFromRect:printButton.frame inView:self.view animated:YES completionHandler:completionHandler]; } else { [printer presentAnimated:YES completionHandler:completionHandler]; }

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  • Measuring the CPU frequency scaling effect

    - by Bryan Fok
    Recently I am trying to measure the effect of the cpu scaling. Is it accurate if I use this clock to measure it? template<std::intmax_t clock_freq> struct rdtsc_clock { typedef unsigned long long rep; typedef std::ratio<1, clock_freq> period; typedef std::chrono::duration<rep, period> duration; typedef std::chrono::time_point<rdtsc_clock> time_point; static const bool is_steady = true; static time_point now() noexcept { unsigned lo, hi; asm volatile("rdtsc" : "=a" (lo), "=d" (hi)); return time_point(duration(static_cast<rep>(hi) << 32 | lo)); } }; Update: According to the comment from my another post, I believe redtsc cannot use for measure the effect of cpu frequency scaling because the counter from the redtsc does not affected by the CPU frequency, am i right?

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  • Is it safe to use a boolean flag to stop a thread from running in C#

    - by Lirik
    My main concern is with the boolean flag... is it safe to use it without any synchronization? I've read in several places that it's atomic. class MyTask { private ManualResetEvent startSignal; private CountDownLatch latch; private bool running; MyTask(CountDownLatch latch) { running = false; this.latch = latch; startSignal = new ManualResetEvent(false); } // A method which runs in a thread public void Run() { startSignal.WaitOne(); while(running) { startSignal.WaitOne(); //... some code } latch.Signal(); } public void Stop() { running = false; startSignal.Set(); } public void Start() { running = true; startSignal.Set(); } public void Pause() { startSignal.Reset(); } public void Resume() { startSignal.Set(); } } Is this a safe way to design a task? Any suggestions, improvements, comments? Note: I wrote my custom CountDownLatch class in case you're wondering where I'm getting it from.

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  • Array of Arrays - writing to File problem

    - by iFloh
    Hi, and again my array of arrays ... I try to improve my app performance by buffering arrays on file for later reuse. I have an NSMutableArray that contains about 30 NSMutableArrays with NSNumber, NSDate and NSString Objects. I try to write the file using this call: bool result = [myArray writeToFile:[fileMethods getFullPath:[NSString stringWithFormat:@"iEts%@.arr", [aDate shortDateString]]] atomically:NO]; = result = FALSE. The Path method is: + (NSString *) getFullPath:(NSString *)forFileName { NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); NSString *documentsDirectory = [paths objectAtIndex:0]; return [documentsDirectory stringByAppendingPathComponent:forFileName]; } and the aDate call returns a shortDateString with ddMMyy. The NSLog NSLog(@"%@", [fileMethods getFullPath:[NSString stringWithFormat:@"iEts%@.arr", [aDate shortDateString]]]); on the path generation returns: /Users/me/Library/Application Support/iPhone Simulator/User/Applications/86729620-EC1D-4C10-A799-0C638BB27933/Documents/iEts010510.arr FURTHER: It must have something to do with the Array of Arrays, since I also write 3 further simple arrays (containing NSStrings) that all succeed. The Array of Arrays gets generated using the addObject method Any ideas what could cause the trouble?

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  • Should this work?

    - by Noah Roberts
    I am trying to specialize a metafunction upon a type that has a function pointer as one of its parameters. The code compiles just fine but it will simply not match the type. #include <iostream> #include <boost/mpl/bool.hpp> #include <boost/mpl/identity.hpp> template < typename CONT, typename NAME, typename TYPE, TYPE (CONT::*getter)() const, void (CONT::*setter)(TYPE const&) > struct metafield_fun {}; struct test_field {}; struct test { int testing() const { return 5; } void testing(int const&) {} }; template < typename T > struct field_writable : boost::mpl::identity<T> {}; template < typename CONT, typename NAME, typename TYPE, TYPE (CONT::*getter)() const > struct field_writable< metafield_fun<CONT,NAME,TYPE,getter,0> > : boost::mpl::false_ {}; typedef metafield_fun<test, test_field, int, &test::testing, 0> unwritable; int main() { std::cout << typeid(field_writable<unwritable>::type).name() << std::endl; std::cin.get(); } Output is always the type passed in, never bool_.

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  • C# textbox cursor positioning

    - by Jim
    I feel like I am just missing a simple property, but can you set the cursor to the end of a line in a textbox? private void txtNumbersOnly_KeyPress(object sender, KeyPressEventArgs e) { if (Char.IsDigit(e.KeyChar) || e.KeyChar == '\b' || e.KeyChar == '.' || e.KeyChar == '-') { TextBox t = (TextBox)sender; bool bHandled = false; _sCurrentTemp += e.KeyChar; if (_sCurrentTemp.Length > 0 && e.KeyChar == '-') { // '-' only allowed as first char bHandled = true; } if (_sCurrentTemp.StartsWith(Convert.ToString('.'))) { // add '0' in front of decimal point t.Text = string.Empty; t.Text = '0' + _sCurrentTemp; _sCurrentTemp = t.Text; bHandled = true; } e.Handled = bHandled; } After testing for '.' as first char, the cursor goes before the text that is added. So instead of "0.123", the results are "1230." without moving the cursor myself. I also apologize if this is a duplicate question.

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  • How to Bind a Command in WPF

    - by MegaMind
    Sometimes we used complex ways so many times, we forgot the simplest ways to do the task. I know how to do command binding, but i always use same approach. Create a class that implements ICommand interface and from the view model i create new instance of that class and binding works like a charm. This is the code that i used for command binding public partial class MainWindow : Window { public MainWindow() { InitializeComponent(); DataContext = this; testCommand = new MeCommand(processor); } ICommand testCommand; public ICommand test { get { return testCommand; } } public void processor() { MessageBox.Show("hello world"); } } public class MeCommand : ICommand { public delegate void ExecuteMethod(); private ExecuteMethod meth; public MeCommand(ExecuteMethod exec) { meth = exec; } public bool CanExecute(object parameter) { return false; } public event EventHandler CanExecuteChanged; public void Execute(object parameter) { meth(); } } But i want to know the basic way to do this, no third party dll no new class creation. Do this simple command binding using a single class. Actual class implements from ICommand interface and do the work.

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  • C++, Ifstream opens local file but not file on HTTP Server

    - by fammi
    Hi, I am using ifstream to open a file and then read from it. My program works fine when i give location of the local file on my system. for eg /root/Desktop/abc.xxx works fine But once the location is on the http server the file fails to open. for eg http://192.168.0.10/abc.xxx fails to open. Is there any alternate for ifstream when using a URL address? thanks. part of the code where having problem: bool readTillEof = (endIndex == -1) ? true : false; // Open the file in binary mode and seek to the end to determine file size ifstream file ( fileName.c_str ( ), ios::in|ios::ate|ios::binary ); if ( file.is_open ( ) ) { long size = (long) file.tellg ( ); long numBytesRead; if ( readTillEof ) { numBytesRead = size - startIndex; } else { numBytesRead = endIndex - startIndex + 1; } // Allocate a new buffer ptr to read in the file data BufferSptr buf (new Buffer ( numBytesRead ) ); mpStreamingClientEngine->SetResponseBuffer ( nextRequest, buf ); // Seek to the start index of the byte range // and read the data file.seekg ( startIndex, ios::beg ); file.read ( (char *)buf->GetData(), numBytesRead ); // Pass on the data to the SCE // and signal completion of request mpStreamingClientEngine->HandleDataReceived( nextRequest, numBytesRead); mpStreamingClientEngine->MarkRequestCompleted( nextRequest ); // Close the file file.close ( ); } else { // Report error to the Streaming Client Engine // as unable to open file AHS_ERROR ( ConnectionManager, " Error while opening file \"%s\"\n", fileName.c_str ( ) ); mpStreamingClientEngine->HandleRequestFailed( nextRequest, CONNECTION_FAILED ); } }

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  • Do you catch expected exceptions in the controller or business service of your asp.net mvc application

    - by Pascal
    I am developing an asp.net mvc application where user1 could delete data records which were just loaded before by user2. User2 either changes this non-existent data record (Update) or is doing an insert with this data in another table that a foreign-key constraint is violated. Where do you catch such expected exceptions? In the Controller of your asp.net mvc application or in the business service? Just a sidenote: I only catch the SqlException here if its a ForeignKey constraint exception to tell the user that another user has deleted a certain parent record and therefore he can not create the testplan. But this code is not fully implemented yet! Controller:   public JsonResult CreateTestplan(Testplan testplan)   {    bool success = false;    string error = string.Empty;    try   {    success = testplanService.CreateTestplan(testplan);    }   catch (SqlException ex)    {    error = ex.Message;    }    return Json(new { success = success, error = error }, JsonRequestBehavior.AllowGet);   } OR Business service: public Result CreateTestplan(Testplan testplan) { Result result = new Result(); try { using (var con = new SqlConnection(_connectionString)) using (var trans = new TransactionScope()) { con.Open(); _testplanDataProvider.AddTestplan(testplan); _testplanDataProvider.CreateTeststepsForTestplan(testplan.Id, testplan.TemplateId); trans.Complete(); result.Success = true; } } catch (SqlException e) { result.Error = e.Message; } return result; } then in the Controller: public JsonResult CreateTestplan(Testplan testplan)   {    Result result = testplanService.CreateTestplan(testplan);       return Json(new { success = result.success, error = result.error }, JsonRequestBehavior.AllowGet);   }

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  • Tree iterator, can you optimize this any further?

    - by Ron
    As a follow up to my original question about a small piece of this code I decided to ask a follow up to see if you can do better then what we came up with so far. The code below iterates over a binary tree (left/right = child/next ). I do believe there is room for one less conditional in here (the down boolean). The fastest answer wins! The cnt statement can be multiple statements so lets make sure this appears only once The child() and next() member functions are about 30x as slow as the hasChild() and hasNext() operations. Keep it iterative <-- dropped this requirement as the recursive solution presented was faster. This is C++ code visit order of the nodes must stay as they are in the example below. ( hit parents first then the children then the 'next' nodes). BaseNodePtr is a boost::shared_ptr as thus assignments are slow, avoid any temporary BaseNodePtr variables. Currently this code takes 5897ms to visit 62200000 nodes in a test tree, calling this function 200,000 times. void processTree (BaseNodePtr current, unsigned int & cnt ) { bool down = true; while ( true ) { if ( down ) { while (true) { cnt++; // this can/will be multiple statesments if (!current->hasChild()) break; current = current->child(); } } if ( current->hasNext() ) { down = true; current = current->next(); } else { down = false; current = current->parent(); if (!current) return; // done. } } }

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  • How to pick a specific object from a Linq Query using Distinct?

    - by Holli
    I have a list with two or more objects of class Agent. Name = "A" Priority = 0 ResultCount = 100 ; Name = "B" Priority = 1 ResultCount = 100 ; Both objects have the same ResultCount. In that case I only need one object and not two or more. I did this with a Linq Query with Distinct and an custom made Comparer. IEnumerable<Agent> distinctResultsAgents = (from agt in distinctUrlsAgents select agt).Distinct(comparerResultsCount); With this query I get only one object from the list but I never know which one. But I don't want just any object, I want object "B" because the Priority is higher then object "A". How can I do that? My custom Comparer is very simple and has a method like this: public bool Equals(Agent x, Agent y) { if (x == null || y == null) return false; if (x.ResultCount == y.ResultCount) return true; return false; }

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  • Predicate usually used for array/list how about here?

    - by amit kohan
    In following code (Josh Smith's article on MVVM), can somebody give me some insight about return _canExecute == null ? true : _canExecute(parameter); ? it is a normal if/else statement but I'm not getting the last part of it. public class RelayCommand : ICommand { #region Fields readonly Action<object> _execute; readonly Predicate<object> _canExecute; #endregion // Fields #region Constructors public RelayCommand(Action<object> execute) : this(execute, null) { } public RelayCommand(Action<object> execute, Predicate<object> canExecute) { if (execute == null) throw new ArgumentNullException("execute"); _execute = execute; _canExecute = canExecute; } #endregion // Constructors #region ICommand Members [DebuggerStepThrough] public bool CanExecute(object parameter) { return _canExecute == null ? true : _canExecute(parameter); } public event EventHandler CanExecuteChanged { add { CommandManager.RequerySuggested += value; } remove { CommandManager.RequerySuggested -= value; } } public void Execute(object parameter) { _execute(parameter); } #endregion // ICommand Members } Thanks.

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  • How would I compare two Lists(Of <CustomClass>) in VB?

    - by Kumba
    I'm working on implementing the equality operator = for a custom class of mine. The class has one property, Value, which is itself a List(Of OtherClass), where OtherClass is yet another custom class in my project. I've already implemented the IComparer, IComparable, IEqualityComparer, and IEquatable interfaces, the operators =, <>, bool and not, and overriden Equals and GetHashCode for OtherClass. This should give me all the tools I need to compare these objects, and various tests comparing two singular instances of these objects so far checks out. However, I'm not sure how to approach this when they are in a List. I don't care about the list order. Given: Dim x As New List(Of OtherClass) From {New OtherClass("foo"), New OtherClass("bar"), New OtherClass("baz")} Dim y As New List(Of OtherClass) From {New OtherClass("baz"), New OtherClass("foo"), New OtherClass("bar")} Then (x = y).ToString should print out True. I need to compare the same (not distinct) set of objects in this list. The list shouldn't support dupes of OtherClass, but I'll have to figure out how to add that in later as an exception. Not interested in using LINQ. It looks nice, but in the few examples I've played with, adds a performance overhead in that bugs me. Loops are ugly, but they are fast :) A straight code answer is fine, but I'd like to understand the logic needed for such a comparison as well. I'm probably going to have to implement said logic more than a few times down the road.

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  • What data stucture should I use for BigInt class

    - by user1086004
    I would like to implement a BigInt class which will be able to handle really big numbers. I want only to add and multiply numbers, however the class should also handle negative numbers. I wanted to represent the number as a string, but there is a big overhead with converting string to int and back for adding. I want to implement addition as on the high school, add corresponding order and if the result is bigger than 10, add the carry to next order. Then I thought that it would be better to handle it as a array of unsigned long long int and keep the sign separated by bool. With this I'm afraid of size of the int, as C++ standard as far as I know guarantees only that int < float < double. Correct me if I'm wrong. So when I reach some number I should move in array forward and start adding number to the next array position. Is there any data structure that is appropriate or better for this? Thanks in advance.

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  • Sharing NSMutableArray

    - by Lucas Veiga
    Hey everbody, im trying to share a NSMutableArray to another xib. The cartList.codigo is a NSMutableArray from a shared class, according to James Brannan's tutorial (http://www.vimeo.com/12164589). When i count it, it gives me 1. But when i load the another view, gives me 0. Whats wrong? View that adds: self.produtoCodigo = [[NSMutableArray alloc]init]; [self.produtoCodigo addObject:@"aa"]; CartViewController *carrinho = [[CartViewController alloc] initWithNibName:@"CartViewController" bundle:[NSBundle mainBundle]]; CartList *lista = [[CartList alloc] init]; carrinho.cartList = lista; carrinho.cartList.codigo = self.produtoCodigo; NSLog(@"QTD %i", [carrinho.cartList.codigo count]); View that wants to load the item added: - (void) viewDidAppear:(BOOL)animated { self.produtoCodigo = self.cartList.codigo; NSLog(@"%i", [self.produtoCodigo count]); [super viewDidLoad]; } Im loading the CartList class in both. Thanks!

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  • Mongodb update: how to check if an update succeeds or fails?

    - by zmg
    I think the title pretty much says it all. I'm working with Mongodb in PHP using the pecl driver. My updates are working great, but I'd like to build some error checking into my funciton(s). I've tried using lastError() in a pretty simple function: function system_db_update_object($query, $values, $database, $collection) { $connection = new Mongo(); $collection = $connection->$database->$collection; $connection->$database->resetError(); //Added for debugging $collection->update( $query, array('$set' => $values)); //$errorArray = $connection->$database->lastError(); var_dump($connection->$database->lastError());exit; // Var dump and /Exit/ } But pretty much regardless of what I try to update (whether it exists or not) I get these same basic results: array(4) { ["err"]=> NULL ["updatedExisting"]=> bool(true) ["n"]=> float(1) ["ok"]=> float(1) } Any help or direction would be greatly appreciated.

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  • Click at specified client area

    - by VixinG
    Click doesn't work - I don't know why and can't find a solution :( ie. Click(150,215) should move mouse to the client area and click there. [DllImport("user32.dll")] private static extern bool ScreenToClient(IntPtr hWnd, ref Point lpPoint); [DllImport("user32", SetLastError = true)] private static extern int SetCursorPos(int x, int y); static void MouseMove(int x, int y) { Point p = new Point(x * -1, y * -1); ScreenToClient(hWnd, ref p); p = new Point(p.X * -1, p.Y * -1); SetCursorPos(p.X, p.Y); } static void Click(int x, int y) { MouseMove(x, y); SendMessage(hWnd, WM_LBUTTONDOWN, (IntPtr)0x1, new IntPtr(y * 0x10000 + x)); SendMessage(hWnd, WM_LBUTTONUP, (IntPtr)0x1, new IntPtr(y * 0x10000 + x)); } Edit: Of course I can use mouse_event for that, but I would like to see a solution for SendMessage()... [DllImport("user32.dll")] static extern void mouse_event(int dwFlags, int dx, int dy, int dwData, int dwExtraInfo); const int LEFTDOWN = 0x00000002; const int LEFTUP = 0x00000004; static void Click(int x, int y) { MouseMove(x, y); mouse_event((int)(LEFTDOWN), 0, 0, 0, 0); mouse_event((int)(LEFTUP), 0, 0, 0, 0); }

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