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• Focus Follows Mouse or Sloppy Focus on Mac OS X

  - by jtimberman

  "Focus follows mouse" or "sloppy focus" is a feature common to X11 window managers on Linux/Unix, including GNOME, KDE, CDE, XFCE and window managers like Enlightenment, Fluxbox and Window Maker. It is also available via TweakUI on Windows. Some individual applications on OS X, like iTerm support it. What is it? Simply put, the window where the mouse pointer is has focus, rather than having to click a window for it to gain focus. Does the native GUI for OS X support this, with some hidden setting? Or, is there a good third party application that will do this?

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• Problems serving SVN over HTTPS on Ubuntu 10.04

  - by odd parity

  We've been experiencing some problems with our Subversion server after upgrading to Ubuntu 10.04. When trying to access a repository, regardless of client (I've tried git-svn and svn on Windows as well as svn on Ubuntu 10.04, from different computers and network locations), I get a 400 bad request. Here's the output from svn: svn: Server sent unexpected return value (400 Bad Request) in response to OPTIONS request for 'https://svn.example.org/svn/programs' Here are the relevant entries from the Apache logs (I'm running Apache 2.2): error.log [Mon Jun 14 11:29:31 2010] [error] [client x.x.x.x] request failed: error reading the headers ssl_access.log x.x.x.x - - [14/Jun/2010:11:29:28 +0200] "OPTIONS /svn/programs HTTP/1.1" 401 2643 "-" "SVN/1.6.6 (r40053) neon/0.29.0" x.x.x.x - - [14/Jun/2010:11:29:31 +0200] "ction-set/></D:options>OPTIONS /svn/programs HTTP/1.1" 400 644 "-" "SVN/1.6.6 (r40053) neon/0.29.0" If anyone has run into similar problems or could give me a pointer to track down the cause of this I'd be very grateful - I'd really like to avoid having to downgrade the box again.

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• Compute divergence of vector field using python

  - by nyvltak

  Is there a function that could be used for calculation of the divergence of the vectorial field? (in matlab http://www.mathworks.ch/help/techdoc/ref/divergence.html) I would expect it exists in numpy/scipy but I can not find it using google :(. # I need to calculate div[A * grad(F)], where F = np.array([[1,2,3,4],[5,6,7,8]]) (2D numpy ndarray) A = np.array([[1,2,3,4],[1,2,3,4]]) (2D numpy ndarray) so grad(F) is a set of 2D ndarrays # I know, I can calculate divergence like this: http://en.wikipedia.org/wiki/Divergence#Application_in_Cartesian_coordinates but do not want to reinvent the wheel. (and also I expent there is some optimized function)

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• [xUbuntu] Move a window back into the visible area?

  - by Johan

  Hi I have this annoying little problem on my laptop that sometimes after I have used a external monitor (with higher resolution) some applications place them self outside the visible area of my desktop. So the question is how do I move them back into the visible area? (please note that no part of the window is visible so I can't use the mouse) Is there some app that can give me focus to move a application to the mouse pointer or something like that? Please note that I'm running xUbuntu (xfce) on this laptop. Thanks Johan

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• Implementing a two-way communication between Microsoft Dynamics CRM and 3rd party app

  - by CxDoo

  I need to implement a bi-directional communication between Microsoft Dynamics CRM and a 3rd party server. The ideal scenario is as follows: User tries to create an entity in CRM In pre-create hook a 3rd party library function is called (or web service or whatever), filled with relevant info, which tries to create the respective entity on the server If the call fails, creation fails in CRM If the call succeeds, the entity is created in the CRM AND additional fields are filled with return values from the call More specifically, I want to do something like this when user tries to create a new entity instance: try { ExternalWebService.CreateTrade(ref TradeInfo info) //this was initialized on the external server myCRM_Trade_Entity.SerialNo = info.SerialNo; CreateNew(myCRM_Trade_Entity); } catch (whatever) { fail; } What would be the suggested way to do this? I am new to Dynamics, have read about Workflows and Plugins but am not sure how should I do this properly.

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• How to get the page in a variable which is going to be displayed in Wordpress ?

  - by KPL

  I want to get the content which are displayed by a particular page in WordPress back-end. Say, for [ROOT]/wp-admin/profile.php I want to remove the First Name and Last Name fields from this page. So, I can run a str_replace() to remove the lines. In this case, I have $search and $replace ... but I need $subject [Ref - http://php.net/manual/en/function.str-replace.php] How to get the $subject ? OR, anybody know any other way to do this?

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• Google API fonts in a select box

  - by Vivek Dragon

  get all available fonts from google font api I like to apply the same function in my Fiddle HTML <select id="styleFont"> <option value="0">Myraid Pro</option> <option value="1">Sans ref</option> <option value="2">Times New Roman</option> <option value="3"> Arial</option> </select> <br> <textarea id="custom_text"></textarea> CSS #custom_text{ resize: none;}? Script $("#styleFont").change(function () { var id =$('#styleFont option' + ':selected').text(); $("#custom_text").css('font-family',id); });? I tried to add the google API fonts in my select box by using https://www.googleapis.com/webfonts/v1/webfonts?key=YOUR-API-KEY how to add this to my html page

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• DataTable Delete Row and AcceptChanges

  - by Pang

  DataTable DT num type name =================================== 001 A Peter 002 A Sam 003 B John public static void fun1(ref DataTable DT, String TargetType) { for (int i = 0; i < DT.Rows.Count; i++) { string type = DT.Rows[i]["type"]; if (type == TargetType) { /**Do Something**/ DT.Rows[i].Delete(); } } DT.AcceptChanges(); } My function get specific data rows in datatable according to the TargetType and use their info to do something. After the datarow is read (match the target type), it will be deleted. However, the row is deleted immediately after .Delete() execute, so the location of the next row (by i) is incorrect. For example, if TargetType is A. When i=0, the "Peter" row is deleted after .Delete executed. Then when i=1, I suppose it will locate the "Sam" row but it actually located "John" row because "Peter" row is deleted. Is there any problem in my codes?

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• Help with query

  - by hdoe123

  Hi, I'm trying make a query that looks at a single table and looks to see if a student is a team called CMHT and in a medic team - if they are I don't want to see the result. I only want see if there only in CMHT or medic not both. Would the right direction be using sub query to filer it out? I've done a search on NOT IN but how could you get to see check if its in more then 2 teams are not? Student Team ref 1 CMHT 1 1 Medic 2 2 Medic 3 this would be in the result 3 CMHT 5 this would be in the result So far I've done the following code would I need use a sub query or do a self join and filter it that way? SELECT Table1.Student, Table1.Team, Table1.refnumber FROM Table1 WHERE (((Table1.Team) In ('Medics','CMHT'))

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• Which are your favorite programming language gadgets?

  - by FerranB

  There are some gadgets/features for programming languages that I like a lot because they save a lot of coding or simply because they are magical or nice. Some of my favorites are: C++ increment/decrement operator: my_array[++c]; C++ assign and sum or substract (...): a += b C# yield return: yield return 1; C# foreach: foreach (MyClass x in MyCollection) PLSQL for loop: for c in (select col1, col2 from mytable) PLSQL pipe row: for i in 1..x loop pipe row(i); end loop; Python Array access operator: a[:1] PLSQL ref cursors. Which are yours?

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• What is the best way to marshal a char array function argument?

  - by Seh Hui 'Felix' Leong

  Let say that given the following signature in LegacyLib.dll: int Login(SysInst *inst, char username[8], char password[6]); The simple way to marshal this function in C# would be: [DllImport("LegacyLib.dll", CharSet=CharSet.Ansi)] public static extern int Login(ref SysInst inst, string username, string password); The problem of doing it in a such a naive way is that the managed string we passed into the username or password parameter could be longer than the array bounds and this could potentially cause a buffer overrun in LegacyLib.dll. Is there a better way which overcomes this problem? i.e. is there any quick [MarshalAs(…)] magic that I could use to counter that?

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• Git push origin master

  - by user306472

  I posted this question early yesterday, but the thread seems to have died out. For reference, see http://stackoverflow.com/questions/2619117/git-push-origin-master . Here's the low-down: I'm new to git. I just set up an account with github and I followed all their instructions flawlessly until I got to the last command of git push origin master Upon entering this command, I get the error message "fatal: No path specified. See 'man git-pull' for valid url syntax." If I type in git origin show the output I see is origin. If I type in git remote -n show the output is * remote origin URL: [email protected]: HEAD branch: (not queried) Local ref configured for 'git push' (status not queried): (matching) pushes to (matching) Please help me get to the bottom of this.

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• SSH tunnel & Rsync thru two proxy/firewalls

  - by cajwine

  Screnario: [internal_server_1]AA------AB[firewall_1]AC----+ 10.2.0.3-^ ^-10.2.0.2 | internet 10.3.0.3-v v-10.3.0.2 | [internal_server_2]BA------BB[firewall_2]BC----+ Ports AC,BC has valid internet addresses. All systems run linux and have root acces to all. Need securely rsync internal_server_1:/some/path into internal_server_2:/another/path My idea is make ssh secure tunnel between two firewalls, e.g. from firewall_1 firewall1# ssh -N -p 22 -c 3des user2@firewall_2.example.com -L xxx/10.3.0.3/xxxx and after will run rsync from internal_server_1 somewhat like: intenal1# rsync -az /some/path [email protected]:/another/path I don't know how to make a correct ssh tunnel for rsync (what ports need tunnel) and to where i will make the rsync? (remote comp address in case of ssh tunnel) Any idea or pointer to helpfull internet resource for this case? thanx.

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• How to center an R plot after removing axis labels

  - by ConnorG

  I'm working on visualizing a matrix in R (almost exactly like http://reference.wolfram.com/mathematica/ref/MatrixPlot.html), and I've been using image(<matrix>,axes=FALSE) to draw the picture. However, I noticed that with the y-axis turned off, the plot isn't centered--the space is still there for the axis ticks + label. I can finagle some centering with par(oma=c(0,0,0,2.5)) but this seems inefficient and error-prone (if my matrix were to change dimensions/become non-square). Is there a better way to force the graphic to center? The right hand margin is significantly smaller than the left.

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• WCF Advanced Books

  - by hgulyan

  Hi, I've read all questions like mine and found a few good links. My question is about architect of WCF, how it is designed, how is generated reference.vb, wsdl and xsd files. How can I do that manually, some good examples of WCF Systems (mostly on desktop applications over TCP). I'd like a book or documentation or anything else, that can give me advanced knowledge of WCF. What do you think of this book http://www.amazon.com/Professional-WCF-Windows-Communication-Foundation/dp/0470563141/ref=sr_1_5?ie=UTF8&s=books&qid=1269425390&sr=8-5 ? And generally is there any source that would give me this all or the only way is practising, trying, looking in all that generated files and reading documentations? Thank you.

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• Google Local Search API

  - by Gublooo

  hey guys couple of quick questions 1) In the local search results - we can get a lot of parameters like street title, address, city, state, lat, long , url etc - In order for me to uniquely identify this record - can I consider URL to be unique to this address or concatenation of latitude and longitude Ref: http://code.google.com/apis/ajaxsearch/documentation/reference.html#_class_GlocalResult 2) In terms of usage, depending upon what user enters, I'm displaying a list of local business for the user to choose. Now when a user selects a particular business address - is it legal for me to store that business address along with lat and longitude information in my database for future look ups. I've seen a lot of blogs talking about storing the lat/long info but just want to be sure that i'm not violating and google rules. Thanks

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• Can DBRefs contain additional fields?

  - by Soviut

  I've encountered several situations when using MongoDB that require the use of DBRefs. However, I'd also like to cache some fields from the referenced document in the DBRef itself. {$ref:'user', $id:'10285102912A', username:'Soviut'} For example, I may want to have the username available even though the user document is referenced. This would provide me all the benefits of a single document approach; Faster querying and eliminating the need to do manual dereferencing in my code. While at the same time allowing me to use references where they make sense. The idea being that when the referenced document is updated (a user changes their name, for example) my business layer can automatically update all the documents that reference it. Ultimately, I'm wondering if it's considered good form to store additional fields on my DBRefs? Will it break anything? Will I lose my data each time a reference is rewritten? Will drivers like pymongo support it?

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• Simulating mouse clicks at specific screen coordinates

  - by Matteo Riva

  I would like to be able to bind some keys to mouse clicks done in specific locations. For example: when I press F1 I should get a left mouse click at coordinates 300x350, F2 at 600x350 and so on. Even better if this could be bound to a specific window application so that coordinates could be relative to it instead of the base desktop. Is there a software which allows this? ADDITION: Ok autohotkey is great but I have problems with my particular setup. Quoting my comment below: I'm using it with an old game (championship manager 01/02) which runs in windowed mode (and I have to set win98 compatibility for it to run): I can get the mouse to move but no click goes to the application I have read this FAQ but it didn't help, this is the script I tried: SendMode Play SetKeyDelay, 0, 50, Play F1::Click 42, 191 F2::ControlSend ahk_class main, Click, Championship Manager 01/02 Still no luck: pointer moves but no click goes through.

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• Why can't I retrieve the entities I've just persisted?

  - by felipecao

  I've got this web service that basically queries the database and returns all persisted entities. For testing purposes, I've created a TestDataManager that persists 2 example entities after Spring context is loaded (BTW, I'm using JAX-WS, Spring, Hibernate and HSQLDB). My TestDataManager looks like this: @Component public class TestDataManager { @Resource private SessionFactory sf; @PostConstruct @Transactional(readOnly = false, propagation = Propagation.REQUIRES_NEW) public void insertTestData(){ sf.openSession(); sf.openSession().beginTransaction(); sf.openSession().persist(new Site("site one")); sf.openSession().persist(new Site("site two")); sf.openSession().flush(); } } My JAX-WS endpoint looks like this: @WebService public class SmartBrickEndpoint { @Resource private WebServiceContext context; public Set<Site> getSitesForUser(String user){ return getSiteService().findByUser(new User(user)); } private ISiteService getSiteService(){ ServletContext servletContext = (ServletContext) context.getMessageContext().get("javax.xml.ws.servlet.context"); return (ISiteService) BeanRetriever.getBean(servletContext, ISiteService.class); } } This my Service class: @Component @Transactional(readOnly = true) public class SiteService implements ISiteService { @Resource private ISiteDao siteDao; @Override public Set<Site> findByUser(User user) { return siteDao.findByUser(user); } } This is my DAO: @Component @Transactional(readOnly = true) public class SiteDao implements ISiteDao { @Resource private SessionFactory sessionFactory; @Override public Set<Site> findByUser(User user) { Set<Site> sites = new LinkedHashSet<Site>(sessionFactory.getCurrentSession().createCriteria(Site.class).list()); return sites; } } This is my applicationContext.xml: <context:annotation-config /> <context:component-scan base-package="br.unirio.wsimxp.dao"/> <context:component-scan base-package="br.unirio.wsimxp.service"/> <context:component-scan base-package="br.unirio.wsimxp.spring"/> <bean id="applicationDS" class="org.springframework.jdbc.datasource.DriverManagerDataSource"> <property name="driverClassName" value="org.hsqldb.jdbcDriver"/> <property name="url" value="jdbc:hsqldb:file:sites"/> </bean> <bean id="sessionFactory" class="org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean"> <property name="dataSource" ref="applicationDS" /> <property name="configLocation"> <value>classpath:hibernate.cfg.xml</value> </property> <property name="hibernateProperties"> <props> <prop key="hibernate.dialect">org.hibernate.dialect.HSQLDialect</prop> <prop key="hibernate.show_sql">true</prop> <prop key="hibernate.format_sql">true</prop> <prop key="hibernate.connection.release_mode">on_close</prop> <!--<prop key="hibernate.current_session_context_class">thread</prop>--> <prop key="hibernate.query.factory_class">org.hibernate.hql.classic.ClassicQueryTranslatorFactory</prop> <prop key="hibernate.hbm2ddl.auto">create-drop</prop> </props> </property> </bean> <bean id="transactionManager" class="org.springframework.orm.hibernate3.HibernateTransactionManager"> <property name="sessionFactory" ref="sessionFactory" /> </bean> <tx:annotation-driven transaction-manager="transactionManager" /> This is what's going on now: when the app is deployed, TestDataManager#insertTestData kicks-in (due to @PostConstruct) and persist does not raise any exception. I should have 2 entities in the DB by now. Afterwards, I invoke the endpoint by a SOAP client, and the request goes all the way up to the DAO. The Hibernate invocation does not raise any exception, but the returned list is empty. The odd thing is, in TestDataManager, if I switch from sf.openSession() to sf.getCurrentSession(), I get an error message: "No Hibernate Session bound to thread, and configuration does not allow creation of non-transactional one here". What I am doing wrong here? Why is the query "not seeing" the persisted entities? Why do I need to invoke sf.openSession() on TestDataManager although it's annotated with @Transactional? I have done some tests with hibernate.current_session_context_class=thread in application.xml, but then I just switch problems in each class. I'd like not needing to manually invoke sf.openSession() and leave that for Hibernate to take care. Thanks a lot for any help!

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• .NET 2.0 vs .NET 4.0 loading error

  - by David Rutten

  My class library is compiled against .NET 2.0 and works just fine whenever I try to load it as a plugin under the 2.0 runtime. If however the master application is running the .NET 4.0 runtime, I get an exception as soon as the resources need to be accessed: Exception occurred during processing of command: Grasshopper Plug-in = Grasshopper Could not find file 'Grasshopper.resources'. Stack trace: at UnhandledExceptionLogger.UnhandledThreadException(Object sender, ThreadExceptionEventArgs args) at System.Windows.Forms.Application.ThreadContext.OnThreadException(Exception t) at System.Windows.Forms.Control.WndProcException(Exception e) at System.Windows.Forms.ControlNativeWindow.OnThreadException(Exception e) at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam) at System.Windows.Forms.SafeNativeMethods.ShowWindow(Handle Ref hWnd, Int32 nCmdShow) at System.Windows.Forms.Control.SetVisibleCore(Boolean value) at System.Windows.Forms.Form.SetVisibleCore(Boolean value) at System.Windows.Forms.Form.Show(IWin32Window owner) .... What's going on and how do I make my project load on all .NET Runtimes?

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• Android PCM Bytes

  - by Pintac

  Hi I am using the AudioRecord class to analize raw pcm bytes as it comes in the mic. So thats working nicely. Now i need convert the pcm bytes into decibel. I have a formula that takes sound presure in Pa into db. db = 20 * log10(Pa/ref Pa) So the question is the bytes i am getting from audiorecorder from the buffer what is it is it amplitude pascal sound pressure or what. I tried to putting the value into te formula but it comes back with very hight db so i do not think its right thanks

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• Using an extended interceptor in struts2 does not work w/ action parameters

  - by Ricardo

  I have a default package w/ an interceptor configure, and i'm extending that package into another one and calling the same interceptor <action name="availability**"> <param name="subTab">availability</param> <interceptor-ref name="tabStack"/> <result>/WEB-INF/jsp/index.jsp?include=visibilit/availability.jsp</result> </action> The problem is that the param is not being read inside my interceptor code: Map params = invocation.getInvocationContext().getParameters(); subTab = params.get("subTab").toString(); //NULL exception Any idea how i can pass parameters to extended interceptors? Thanks!

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• Is this a correct Interlocked synchronization design?

  - by Dan Bryant

  I have a system that takes Samples. I have multiple client threads in the application that are interested in these Samples, but the actual process of taking a Sample can only occur in one context. It's fast enough that it's okay for it to block the calling process until Sampling is done, but slow enough that I don't want multiple threads piling up requests. I came up with this design (stripped down to minimal details): public class Sample { private static Sample _lastSample; private static int _isSampling; public static Sample TakeSample(AutomationManager automation) { //Only start sampling if not already sampling in some other context if (Interlocked.CompareExchange(ref _isSampling, 0, 1) == 0) { try { Sample sample = new Sample(); sample.PerformSampling(automation); _lastSample = sample; } finally { //We're done sampling _isSampling = 0; } } return _lastSample; } private void PerformSampling(AutomationManager automation) { //Lots of stuff going on that shouldn't be run in more than one context at the same time } } Is this safe for use in the scenario I described?

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• When my UIViewController accesses an NSArray in my AppDelegate from an IBAction it crashes the progr

  - by JasonClark

  I have a couple UIViewControllers that I am trying to access an array inside my AppDelegate. When I use an IBAction UIButton and in that method I access my AppDelegate my program dies silently. Nothing in output or the debugger, it just stops. If I run it several times I can see that it is failing to access the array properly. To investigate this problem I created a very basic app. In my AppDelegate.h I declared and set properties for the array #import <UIKit/UIKit.h> @class MyViewController; @interface MyAppDelegate : NSObject <UIApplicationDelegate> { UIWindow *window; MyViewController *viewController; NSArray *images; } @property (nonatomic, retain) NSArray *images; @property (nonatomic, retain) IBOutlet UIWindow *window; @property (nonatomic, retain) IBOutlet MyViewController *viewController;` In the AppDelegate.m I synthesised and initialized the NSArray (Also made sure the images were added to the Resources folder). @synthesize images; - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions { images = [NSArray arrayWithObjects: [[NSBundle mainBundle] pathForResource:@"bamboo_nw" ofType:@"jpg"], ..... nil]; NSLog(@"init images size:%i",[images count]); [window addSubview:viewController.view]; [window makeKeyAndVisible]; return YES; } In my UIViewController.h I added class, imported header file, declared, and set properties for my AppDelegate pointer. #import <UIKit/UIKit.h> #import "MyAppDelegate.h" @class MyAppDelegate; @interface MyViewController : UIViewController { MyAppDelegate *mainDelegate; IBOutlet UIButton mybutton; } @property (nonatomic, retain) MyAppDelegate mainDelegate; @property (nonatomic, retain) UIButton *mybutton; -(IBAction) doSomething;` In my UIViewController.m I synthesize and assign my AppDelegate. I set up an IBAction that will log the same count of the NSArray from the AppDelegate. #import "MyViewController.h" #import "MyAppDelegate.h" @implementation MyViewController @synthesize mybutton; - (void)viewDidLoad { mainDelegate = (MyAppDelegate *)[[UIApplication sharedApplication] delegate]; NSLog(@"vdl images size:%i",[mainDelegate.images count]); [super viewDidLoad]; } -(IBAction) doSomething { NSLog(@"ds images size:%i",[mainDelegate.images count]); } I print the size of the NSArray in the AppDelegate when I create it, in the ViewController when I first assign my AppDelegate pointer, and then as a result of my IBAction. I find that everytime I hit the button the program dies. On the third time I hit the button, I saw that it ran my IBAction but printed my array size as 1 instead of 8. Am I missing something? Also, why don't I get stack traces or anything, the debugger just dies silently? Thanks in advance for any help! Debugger Console output for 3 runs: [Session started at 2010-05-10 06:21:32 -0700.] 2010-05-10 06:21:44.865 My[59695:207] init images size:8 2010-05-10 06:21:47.246 My[59695:207] vdl images size:8 [Session started at 2010-05-10 06:22:15 -0700.] 2010-05-10 06:22:18.920 My[59704:207] init images size:8 2010-05-10 06:22:19.043 My[59704:207] vdl images size:8 [Session started at 2010-05-10 06:22:23 -0700.] 2010-05-10 06:22:25.966 My[59707:207] init images size:8 2010-05-10 06:22:26.017 My[59707:207] vdl images size:8 2010-05-10 06:22:27.814 My[59707:207] ds images size:1

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• Boost::Spirit::Qi autorules -- avoiding repeated copying of AST data structures

  - by phooji

  I've been using Qi and Karma to do some processing on several small languages. Most of the grammars are pretty small (20-40 rules). I've been able to use autorules almost exclusively, so my parse trees consist entirely of variants, structs, and std::vectors. This setup works great for the common case: 1) parse something (Qi), 2) make minor manipulations to the parse tree (visitor), and 3) output something (Karma). However, I'm concerned about what will happen if I want to make complex structural changes to a syntax tree, like moving big subtrees around. Consider the following toy example: A grammar for s-expr-style logical expressions that uses autorules... // Inside grammar class; rule names match struct names... pexpr %= pand | por | var | bconst; pand %= lit("(and ") >> (pexpr % lit(" ")) >> ")"; por %= lit("(or ") >> (pexpr % lit(" ")) >> ")"; pnot %= lit("(not ") >> pexpr >> ")"; ... which leads to parse tree representation that looks like this... struct var { std::string name; }; struct bconst { bool val; }; struct pand; struct por; struct pnot; typedef boost::variant<bconst, var, boost::recursive_wrapper<pand>, boost::recursive_wrapper<por>, boost::recursive_wrapper<pnot> > pexpr; struct pand { std::vector<pexpr> operands; }; struct por { std::vector<pexpr> operands; }; struct pnot { pexpr victim; }; // Many Fusion Macros here Suppose I have a parse tree that looks something like this: pand / ... \ por por / \ / \ var var var var (The ellipsis means 'many more children of similar shape for pand.') Now, suppose that I want negate each of the por nodes, so that the end result is: pand / ... \ pnot pnot | | por por / \ / \ var var var var The direct approach would be, for each por subtree: - create pnot node (copies por in construction); - re-assign the appropriate vector slot in the pand node (copies pnot node and its por subtree). Alternatively, I could construct a separate vector, and then replace (swap) the pand vector wholesale, eliminating a second round of copying. All of this seems cumbersome compared to a pointer-based tree representation, which would allow for the pnot nodes to be inserted without any copying of existing nodes. My question: Is there a way to avoid copy-heavy tree manipulations with autorule-compliant data structures? Should I bite the bullet and just use non-autorules to build a pointer-based AST (e.g., http://boost-spirit.com/home/2010/03/11/s-expressions-and-variants/)?

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