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• Facebook offline access step-by-step

  - by Ben

  After searchinge litteraly 1 day on fb and google for an up-to-date and working way to do something seemingly simple: I am looking for a step-by-step explanation to get offline_access for a user for a facebook app and then using this (session key) to retrieve offline & not within a browser friends & profile data. Preferrably doing this in the Fb Java API. Thanks. And yes I did check the facebook wiki. Update: Anyone? this: http://www.facebook.com/authorize.php?api_key=<api-key>&v=1.0&ext_perm=offline_access gives me offline_Access, however how to retrieve the session_key? Why can't facebook just do simple documentation, I mean there are like 600 people working there? The seemingly same question: http://stackoverflow.com/questions/617043/getting-offlineaccess-to-work-with-facebook Does not answer how to retrieve the session key Edit: I am still stuck with that. I guess nobody really tried such a batch access out yet...

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• Application design question, best approach?

  - by Jamie Keeling

  Hello, I am in the process of designing an application that will allow you to find pictures (screen shots) made from certain programs. I will provide the locations of a few of the program in the application itself to get the user started. I was wondering how I should go about adding new locations as the time goes on, my first thought was simply hard coding it into the application but this will mean the user has to reinstall it to make the changes take affect. My second idea was to use an XML file to contain all the locations as well as other data, such as the name of the application. This also means the user can add their own locations if they wish as well as sharing them over the internet. The second option seemed the best approach but then I had to think how would it be managed on the users computer. Ideally I'd like just a single .exe without the reliance on any external files such as the XML but this would bring me back to point one. Would it be best to simply use the ClickOnce deployment to create an entry in the start menu and create a folder containing the .exe and the file names? Thanks for the feedback, I don't want to start implementing the application until the design is nailed.

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• Dockable panes created in CChildFrame not visible the second time the app. starts.

  - by Nijenhuis

  Hi, I have created some dockable panes in CChildFrame::OnCreate() The first time i start the application they are shown. The second time i start the application they are created but the splitterwindows are completly against the sides of the clients area (bottom and right), so not visible. So i have to use the mouse to pull the splitters into the clientarea so that the dockable windows become visible again. If i do File-New in my app a new client window is created and showing the dockable windows as they should be. I Think this has something to do with saving the windows layout in the registry, because if i change SetRegistryKey(_T("61sakjgsajkdg")); in the CWinApp derived class of my app. and rerun they are shown again the first time. (but not the second time i restart the app). How can i save the layout of those dockable windows as well, so if i restart my app. they are visible ? Or else how do i prevent my app. of overwritting the window layout with the one previously saved. Something to do with LoadCustomState() and SaveCustomState() ?, i could no find any info on howto implement those methods. I have here a link to the demo project to demonstrate what i mean: http://www.4shared.com/file/237193472/c384f0f6/GUI60.html Could someone tell me how to show those dockable windows in my CChildFrame class the second time the app starts?

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• How to pass data from selected rows using checkboxes from JSP to the server

  - by eddy

  Hi, I'd like to know if there's any way to send data to the server for the selected rows using the checkboxes I've put on those rows? I mean , how can I send only the data (in this case mileage ) of those selected rows (selected with the checkboxes) to the server ? see the image Here's the html code I use: <table> <thead> <tr class="tableheader"> <td width="10%"></td> <td width="30%">Vehicle</td> <td width="40%">Driver</td> <td width="10%">Mileage</td> </tr> </thead> <tbody> <c:forEach items="${list}" var="item"> <tr> <td align="center"> <input type="checkbox" name="selectedItems" value="c:out value="${item.numberPlate}"/>"/> </td> <td align="left"><c:out value="${item.numberPlate}"/></td> <td align="left"><c:out value="${item.driver.fullName}" /></td> <td align="left"><input type="text" name="mileage" value="" /></td> </tr> </c:forEach> </tbody> </table> I really hope you can give some guidance on this. Thanks in beforehand.

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• How to use keyword this in a mouse wrapper in right context in Javascript?

  - by MartyIX

  Hi, I'm trying to write a simple wrapper for mouse behaviour. This is my current code: function MouseWrapper() { this.mouseDown = 0; this.OnMouseDownEvent = null; this.OnMouseUpEvent = null; document.body.onmousedown = this.OnMouseDown; document.body.onmouseup = this.OnMouseUp; } MouseWrapper.prototype.Subscribe = function (eventName, fn) { // Subscribe a function to the event if (eventName == 'MouseDown') { this.OnMouseDownEvent = fn; } else if (eventName == 'MouseUp') { this.OnMouseUpEvent = fn; } else { alert('Subscribe: Unknown event.'); } } MouseWrapper.prototype.OnMouseDown = function () { this.mouseDown = 1; // Fire event $.dump(this.OnMouseDownEvent); if (this.OnMouseDownEvent != null) { alert('test'); this.OnMouseDownEvent(); } } MouseWrapper.prototype.OnMouseUp = function () { this.mouseDown = 0; // Fire event if (this.OnMouseUpEvent != null) { this.OnMouseUpEvent(); } } From what I gathered it seems that in MouseWrapper.prototype.OnMouseUp and MouseWrapper.prototype.OnMouseDown the keyword "this" doesn't mean current instance of MouseWrapper but something else. And it makes sense that it doesn't point to my instance but how to solve the problem? I want to solve the problem properly I don't want to use something dirty. My thinking: * use a singleton pattern (mouse is only one after all) * pass somehow my instance to OnMouseDown/Up - how? Thank you for help!

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• Clarification of atomic memory access for different OSs

  - by murrekatt

  I'm currently porting a Windows C++ library to MacOS as a hobby project as a learning experience. I stumbled across some code using the Win Interlocked* functions and thus I've been trying to read up on the subject in general. Reading related questions here in SO, I understand there are different ways to do these operations depending on the OS. Interlocked* in Windows, OSAtomic* in MacOS and I also found that compilers have builtin (intrinsic) operations for this. After reading gcc builtin atomic memory access, I'm left wondering what is the difference between intrinsic and the OSAtomic* or Interlocked* ones? I mean, can I not choose between OSAtomic* or gcc builtin if I'm on MacOS when I use gcc? The same if I'd be on Windows using gcc. I also read that on Windows Interlocked* come as both inline and intrinsic versions. What to consider when choosing between intrinsic or inline? In general, are there multiple options on OSs what to use? Or is this again "it depends"? If so, what does it depend on? Thanks!

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• What algorithms compute directions from point A to point B on a map?

  - by A. Rex

  How do map providers (such as Google or Yahoo! Maps) suggest directions? I mean, they probably have real-world data in some form, certainly including distances but also perhaps things like driving speeds, presence of sidewalks, train schedules, etc. But suppose the data were in a simpler format, say a very large directed graph with edge weights reflecting distances. I want to be able to quickly compute directions from one arbitrary point to another. Sometimes these points will be close together (within one city) while sometimes they will be far apart (cross-country). Graph algorithms like Dijkstra's algorithm will not work because the graph is enormous. Luckily, heuristic algorithms like A* will probably work. However, our data is very structured, and perhaps some kind of tiered approach might work? (For example, store precomputed directions between certain "key" points far apart, as well as some local directions. Then directions for two far-away points will involve local directions to a key points, global directions to another key point, and then local directions again.) What algorithms are actually used in practice? PS. This question was motivated by finding quirks in online mapping directions. Contrary to the triangle inequality, sometimes Google Maps thinks that X-Z takes longer and is farther than using an intermediate point as in X-Y-Z. But maybe their walking directions optimize for another parameter, too? PPS. Here's another violation of the triangle inequality that suggests (to me) that they use some kind of tiered approach: X-Z versus X-Y-Z. The former seems to use prominent Boulevard de Sebastopol even though it's slightly out of the way. (Edit: this example doesn't work anymore, but did at the time of the original post. The one above still works as of early November 2009.)

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• Pointers, am I doing them correctly? Objective-c/cocoa

  - by Chris

  I have this in my @interface struct track currentTrack; struct track previousTrack; int anInt; Since these are not objects, I do not have to have them like int* anInt right? And if setting non-object values like ints, boolean, etc, I do not have to release the old value right (assuming non-GC environment)? The struct contains objects: typedef struct track { NSString* theId; NSString* title; } *track; Am I doing that correctly? Lastly, I access the struct like this: [currentTrack.title ...]; currentTrack.theId = @"asdf"; //LINE 1 I'm also manually managing the memory (from a setter) for the struct like this: [currentTrack.title autorelease]; currentTrack.title = [newTitle retain]; If I'm understanding the garbage collection correctly, I should be able to ditch that and just set it like LINE 1 (above)? Also with garbage collection, I don't need a dealloc method right? If I use garbage collection does this mean it only runs on OS 10.5+? And any other thing I should know before I switch to garbage collected code? Sorry there are so many questions. Very new to objective-c and desktop programming. Thanks

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• How to output multicolumn html without "widows"?

  - by user314850

  I need to output to HTML a list of categorized links in exactly three columns of text. They must be displayed similar to columns in a newspaper or magazine. So, for example, if there are 20 lines total the first and second columns would contain 7 lines and the last column would contain 6. The list must be dynamic; it will be regularly changed. The tricky part is that the links are categorized with a title and this title cannot be a "widow". If you have a page layout background you'll know that this means the titles cannot be displayed at the bottom of the column -- they must have at least one link underneath them, otherwise they should bump to the next column (I know, technically it should be two lines if I were actually doing page layout, but in this case one is acceptable). I'm having a difficult time figuring out how to get this done. Here's an example of what I mean: Shopping Link 3 Link1 Link 1 Link 4 Link2 Link 2 Link 3 Link 3 Cars Link 1 Music Games Link 2 Link 1 Link 1 Link 2 News As you can see, the "News" title is at the bottom of the middle column, and so is a "widow". This is unacceptable. I could bump it to the next column, but that would create an unnecessarily large amount of white space at the bottom of the second column. What needs to happen instead is that the entire list needs to be re-balanced. I'm wondering if anyone has any tips for how to accomplish this, or perhaps source code or a plug in. Python is preferable, but any language is fine. I'm just trying to get the general concept down.

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• Dropping not working on Chrome Mac version

  - by user600641

  I tried to work with html5 drag&drop api, and it works very well on my chrome 20.0.1132 on windows machine, but most fun - that the same version of chrome on mac os lion is not working. I mean dragstart is working, but drop event, dragleave, dragover is not fired. Here is html: <form id="fake_form" action="#" > <div id="canvas_wrapper" style="overflow: hidden;width: 600px; position: relative;border: 1px solid black; margin-left: 30px;"> <canvas width="600" height="300" > </canvas> </div> </form> Here is javascript: var canvas = $('canvas')[0]; canvas.addEventListener('dragenter', function(e){ console.log('dragenter'); }, false); canvas.addEventListener('dragleave', function(){ console.log('dragleave'); }, false) canvas.addEventListener('dragover', function(e){ console.log('dragover'); if(e.preventDefault){ e.preventDefault(); } return false; }, false); canvas.ondrop = function(e){ console.log('ondrop'); /** OTHER CODE **/ If it helps: on safari on the same mac - it works, i`m dragging image tags some of them have draggable attribute, some of them - not. Just checked - on canary mac version 22 it works. UPDATE: i figured out that there is some magic with dragstart event, if i delete line with this e.dataTransfer.setData('src', src_var) everythings become working

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• problem creating jpg thumb with php

  - by Ross

  Hi, I am having problems creating a thumbnail from an uploaded image, my problem is (i) the quality (ii) the crop http://welovethedesign.com.cluster.cwcs.co.uk/phpimages/large.jpg http://welovethedesign.com.cluster.cwcs.co.uk/phpimages/thumb.jpg If you look the quality is very poor and the crop is taken from the top and is not a resize of the original image although the dimesions mean it is in proportion. The original is 1600px wide by 1100px high. Any help would be appreciated. $thumb = $targetPath."Thumbs/".$fileName; $imgsize = getimagesize($targetFile); $image = imagecreatefromjpeg($targetFile); $width = 200; //New width of image $height = 138; //This maintains proportions $src_w = $imgsize[0]; $src_h = $imgsize[1]; $thumbWidth = 200; $thumbHeight = 138; // Intended dimension of thumb // Beyond this point is simply code. $sourceImage = imagecreatefromjpeg($targetFile); $sourceWidth = imagesx($sourceImage); $sourceHeight = imagesy($sourceImage); $targetImage = imagecreate($thumbWidth,$thumbHeight); imagecopyresized($targetImage,$sourceImage,0,0,0,0,$thumbWidth,$thumbWidth,imagesx($sourceImage),imagesy($sourceImage)); //imagejpeg($targetImage, "$thumbPath/$thumbName"); imagejpeg($targetImage, $thumb); chmod($thumb, 0755);

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• Using maven to distribute a swing application that can have each dependency individually tracked

  - by tms

  I'm moving my project to Maven and eventually OSGi. I currently distribute the project is a large Zip file with all the dependencies. Although my projects code is only 20% of the total package I have to redistribute all the dependency. With smaller independent modules this may be even less. Looking here on stack overflow it seems that to keep my current plan the maven-assembly-plugin should do the trick. I was considering having a base installer that would look at a XML manifest, then collect all the libraries that needed to be updated. This would mean that libraries that change occasionally would be downloaded less often. This also makes since for something like OSGi plugins (which could have independent release schedules). In essence I want my software to look and manage individual libraries, and download on demand (based on the manifest). I was wondering if there is a "maven way" of generating this Manifest and publishing all the libraries to a website? I believe the deploy life-cycle would do the second step. As an alternative, is there a OpenSource Java library that does this type of deployment? I don't want to embed Maven or something larger with the distributed code. The application is not for coders, the simpler the better, and the smaller the installer the better.

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• How can I get an IObservable<T> in Rx from a "non-standard" event?

  - by Dan Tao

  Here's what I mean. Suppose I'm working with an API that exposes events, but these events do not follow the standard EventHandler or EventHandler<TEventArgs> signature. One event might look like this, for instance: Public Event Update(ByVal sender As BaseSubscription, ByVal e As BaseEvent) Now, typically, if I want to get an IObservable<TEventArgs> from an event, I can just do this: Dim updates = Observable.FromEvent(Of UpdateEventArgs)( _ target:=updateSource, _ eventName:="Update" _ ) But this doesn't work, because the Update event is not an EventHandler<UpdateEventArgs> -- in fact, there is no UpdateEventArgs -- it's basically just its own thing. Obviously, I could define my own class deriving from EventArgs (i.e., UpdateEventArgs), write another class to wrap the object providing the Update event, give the wrapper class its own Update event that is an EventHandler<UpdateEventArgs>, and get an IObservable<UpdateEventArgs> from that. But that's an annoying amount of work. Is there some way to create an IObservable<[something]> from a "non-standard" event like this, or am I out of luck?

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• Right way to return proxy model instance from a base model instance in Django ?

  - by sotangochips

  Say I have models: class Animal(models.Model): type = models.CharField(max_length=255) class Dog(Animal): def make_sound(self): print "Woof!" class Meta: proxy = True class Cat(Animal): def make_sound(self): print "Meow!" class Meta: proxy = True Let's say I want to do: animals = Animal.objects.all() for animal in animals: animal.make_sound() I want to get back a series of Woofs and Meows. Clearly, I could just define a make_sound in the original model that forks based on animal_type, but then every time I add a new animal type (imagine they're in different apps), I'd have to go in and edit that make_sound function. I'd rather just define proxy models and have them define the behavior themselves. From what I can tell, there's no way of returning mixed Cat or Dog instances, but I figured maybe I could define a "get_proxy_model" method on the main class that returns a cat or a dog model. Surely you could do this, and pass something like the primary key and then just do Cat.objects.get(pk = passed_in_primary_key). But that'd mean doing an extra query for data you already have which seems redundant. Is there any way to turn an animal into a cat or a dog instance in an efficient way? What's the right way to do what I want to achieve?

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• Python CGI Premature end of script error depending on script parameters.

  - by nickengland

  I have a python script which should parse a file and produce some output to disk, as well as returning a webpage linking to the outputted files. When run with a file posted from the HTML form I get no HTML output back, just a 500 error page and the error_log contains the line: [Mon Apr 19 15:03:23 2010] [error] [client xxx.xxx.121.79] Premature end of script headers: uploadcml.py, referer: http://xxx.ch.cam.ac.uk:9000/ However, the files which the script should be saving are indeed saved to disk. If I run it without any arguments, the script returns the correct HTML indicating no file was parsed. All the information I have found on the web about Premature end of script headers implies it is due to either a missing header, or lack of permissions on the python script but neither can apply to me. The first lines of the script are: #!/home/nwe23/bin/bin/python import cgitb; cgitb.enable() import cgi import pybel,openbabel import random print "Content-Type: text/html" print so when run, I can see no way for it to fail to output the header, and it DOES output the header when run without a file to parse, but when given a file produces the error(but still parsed the file and saves the output to disk!). Does anyone know how this is happening and what can be done to fix it? I have tried adding wrongly-indented gibberish (such as foobar) at various points in the file, and this results in adding an indent error to the error_log wherever it is, even if its the very last line in the script. The Premature script headers error remains though. Does this mean the script is executing all the way through?

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• Got Hacked. Want to understand how.

  - by gaoshan88

  Someone has, for the second time, appended a chunk of javascript to a site I help run. This javascript hijacks Google adsense, inserting their own account number, and sticking ads all over. The code is always appended, always in one specific directory (one used by a third party ad program), affects a number of files in a number of directories inside this one ad dir (20 or so) and is inserted at roughly the same overnight time. The adsense account belongs to a Chinese website (located in a town not an hour from where I will be in China next month. Maybe I should go bust heads... kidding, sort of), btw. So, how could they append text to these files? Is it related to the permissions set on the files (ranging from 755 to 644)? To the webserver user (it's on MediaTemple so it should be secure, yes?)? I mean, if you have a file that has permissions set to 777 I still can't just add code to it at will... how might they be doing this?

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• Proper way of naming your Java Google App Engine Project

  - by Saif Bechan

  I am starting out with Google's App Engine in Java. I have seen the tutorial video but I do not understand the naming of the project package. It is going to be a guestbook, that's why the name is guestbook, I understand that part. But after that I see package name. 1)Is that something you import into the project, or is is something you create. I have seen this a lot in projects, something like com.xxx.xxx. 2)How do you name this type of thing or is this an import. I have looked at another tutorial there they take the naming to a whole new level. The name of both the project and the package is de.vogella.gae.java.todo. 3)What does this mean in java terms. 4)Maybe one of you can help me with this specific project I want to start. I want to create a Google App project that for now only serves static files. I will leave the project empty and just put all my static files in the war directory of the project. I want the domain name to be mydomainstatic

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• Where to master HTML, CSS ans Javascript?

  - by Shahensha

  I got interested in web-development lately. I am still a student. I learnt basics of HTML, CSS and JavaScript! Then I thought I should improve my server side scripting. So I am learning Struts2 and I am doing better there. Now I have decided I should finally put my skill to some use. So I and my friend have decided to come up with a fun website for our class. But now I am realizing that, though I know server-side scripting to a good extent (not great, just good considering I am a beginner), I am nowhere near good in the basic elements viz. HTML, CSS and JavaScript! I mean, I can't do cool stuff with it. I am aware of w3schools, but it would be great if you can point out a more intuitive place where I can learn to do all the cool stuff in a short time. Some of the problems I am facing are: 1) How should I design the basic layout of my website? 2) How can I use 3rd party APIs like that of Facebook graph? regards shahensha

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• javascript: "Object doesn't support this property or method" when ActiveX object called.

  - by agnieszka

  I've got simple html on Login.aspx with an ActiveX object: <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html> <head><title></title> <script language="javaScript" type="text/javascript"> function getUserInfo() { var userInfo = MyActiveX.GetInfo(); form1.info.value = userInfo; form1.submit(); } </script> </head> <body onload="javascript:getUserInfo()"> <object id="MyActiveX" name="MyActiveX" codebase="MyActiveX.cab" classid="CLSID:C63E6630-047E-4C31-H457-425C8412JAI25"></object> <form name="form1" method="post" action="Login.aspx"> <input type="hidden" id="info" name="info" value="" /> </form> </body> </html> The code works perfectly fine on my machine (edit: hosted and run), it does't work on the other: there is an error "Object doesn't support this property or method" in the first line of javascript function. The cab file is in the same folder as the page file. I don't know javascript at all and have no idea why is the problem occuring. Googling didn't help. Do you ave any idea? Edit: on both machines IE was used and activex was enabled. Edit2: I also added if (document.MyActiveX) at the beggining of the function and I still get error in the same line of code - I mean it looks like document.MyActiveX is true but calling the method still fails

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• Class design when working with dataset

  - by MC

  If you have to retrieve data from a database and bring this dataset to the client, and then allow the user to manipulate the data in various ways before updating the database again, what is a good class design for this if the data tables will not have a 1:1 relationship with the class objects? Here are some I came up with: Just manipulate the DataSet itself on the client and then send it back to the database as is. This will work though obviously the code will be very dirty and not well-structured. Same as #1, but wrap the dataset code around classes. What I mean is that you may have a class that takes a dataset or a datatable in its constructor, and then provides public methods and properties to simplify the code. Inside these methods and properties it will be reading or manipulating the dataset. To update the database afterwards will be easy because you already have the updated dataset. Get rid of the dataset entirely on the client, convert to objects, then convert back to a dataset when needing to update the database. Is there any good resources where I can find information on this?

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• jQuery and jQuery UI (Dual Licensing)

  - by John Hartsock

  OK I have read many posts regarding Dual Licensing using MIT and GPL licenses. But Im curious still, as the wording seems to be inclusive. Many of the Dual Licenses state that the software is licensed using "MIT AND GPL". The "AND" is what confuses me. It seems to me that the word "AND" in the terms, means you will be licensing the product using both licenses. Most of the posts, here on stackoverflow, say you can license the software using one "OR" the other. JQuery specifically states "OR", whereas JQuery UI specifically States "AND". Another Instance of the "AND" would be JQGrid. Im not a lawyer but, it seems to me that a legal interpretation of this would state that use of the software would mean that your using the software under both licenses. Has anyone who has contacted a lawyer gotten clarification or a definitive answer as to what is true? Can you use Dual licensed software products that state "AND" in the terms of agreement under either license?

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• Thread Safety of C# List<T> for readers

  - by ILIA BROUDNO

  I am planning to create the list once in a static constructor and then have multiple instances of that class read it (and enumerate through it) concurrently without doing any locking. In this article http://msdn.microsoft.com/en-us/library/6sh2ey19.aspx MS describes the issue of thread safety as follows: Public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe. A List can support multiple readers concurrently, as long as the collection is not modified. Enumerating through a collection is intrinsically not a thread-safe procedure. In the rare case where an enumeration contends with one or more write accesses, the only way to ensure thread safety is to lock the collection during the entire enumeration. To allow the collection to be accessed by multiple threads for reading and writing, you must implement your own synchronization. The "Enumerating through a collection is intrinsically not a thread-safe procedure." Statement is what worries me. Does this mean that it is thread safe for readers only scenario, but as long as you do not use enumeration? Or is it safe for my scenario?

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• Named previously unnamed branch

  - by Jab

  It seems naming a previously unnamed branch doesn't really work out. It creates a nasty multiple heads problem that I can't find a solution for. Here is the workflow... UserA starts working on feature that they expect to be small, so they just start working(off the default branch). The change turns out to be a large project and will need multiple contributors. So UserA issues... hg branch "Feature1" and continues working, committing locally s needed. UserA then pulls down the changes from the central repo so he can push. At this point, why does hg heads return 3 heads? It shows 2 for default and 1 for Feature1. The first head for default is the latest change by another user on the branch(irrelevant). The second default head is the commit prior to the hg branch "Feature1" commit. The central repository has rules enforced so that only 1 head per branch is allowed, so forcing a push isn't an option. The repo doesn't want multiple heads on the default branch. UserA should be able to push these changes so that other users can see the Feature1 branch and help out. I can't seem to find a way to "correct" this. I don't think I can re-write the branch of the initial commits for the feature, before it was a named branch. I know the initial changes before the named branch are technically on the default branch, but does that mean they will be heads until that Feature1 branch is merged?

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• C++ - passing references to boost::shared_ptr

  - by abigagli

  If I have a function that needs to work with a shared_ptr, wouldn't it be more efficient to pass it a reference to it (so to avoid copying the shared_ptr object)? What are the possible bad side effects? I envision two possible cases: 1) inside the function a copy is made of the argument, like in ClassA::take_copy_of_sp(boost::shared_ptr<foo> &sp) { ... m_sp_member=sp; //This will copy the object, incrementing refcount ... } 2) inside the function the argument is only used, like in Class::only_work_with_sp(boost::shared_ptr<foo> &sp) //Again, no copy here { ... sp->do_something(); ... } I can't see in both cases a good reason to pass the boost::shared_ptr by value instead of by reference. Passing by value would only "temporarily" increment the reference count due to the copying, and then decrement it when exiting the function scope. Am I overlooking something? Andrea. EDIT: Just to clarify, after reading several answers : I perfectly agree on the premature-optimization concerns, and I alwasy try to first-profile-then-work-on-the-hotspots. My question was more from a purely technical code-point-of-view, if you know what I mean.

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• MVC 3, View Model for user registration process. Password validation not working properly

  - by sec_goat

  I am trying to create a user registration page using MVC 3, so that I can better understand the process of how it works, what's going on behind the scenes etc. I am running into some issues when trying to use [Compare] to check to see that the user entered the same password twice. I tried adding the ComparePassword field to my user model first, and found that would not work the way I wanted as I did not have the field in the database, so the obvious answer was to create a View Model using the same information including the ComparePassword field. So I now have created a User model and a RegistrationViewModel, however it appears that the [Compare] on the password is not returning anything, for instance no matter what I put in the two boxes, when I click create it gives no error, which seems to me to mean it was successfully validated. I am not sure what I am doing or not doing to make this work properly. I have tried updating the jQuery.Validate to the newest version as there were some bugs reported in older version, this has not helped my efforts. Below is a wall of code, that is what I am working with. } public class RegistrationViewModel { [Required] [StringLength(15, MinimumLength = 3)] [Display(Name = "User Name")] [RegularExpression(@"(\S)+", ErrorMessage = " White Space is not allowed in User Names")] [ScaffoldColumn(false)] public String Username { get; set; } [Required] [StringLength(15, MinimumLength = 3)] [Display(Name = "First Name")] public String firstName { get; set; } [Required] [StringLength(15, MinimumLength = 3)] [Display(Name = "Last Name")] public String lastName { get; set; } [Required] [Display(Name = "Email")] public String email { get; set; } [Required] [Display(Name = "Password")] [DataType(DataType.Password)] public String password { get; set; } [Required] [DataType(DataType.Password)] [Display(Name = "Re-enter Password")] [Compare("Password", ErrorMessage = "Passwords do not match.")] public String comparePassword { get; set; } }

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