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  • Special technology needed for browser based chat?

    - by orokusaki
    On this post, I read about the usage of XMPP. Is this sort of thing necessary, and more importantly, my main question expanded: Can a chat server and client be built efficiently using only standard HTTP and browser technologies (such as PHP and JS, or RoR and JS, etc)? Or, is it best to stick with old protocols like XMPP find a way to integrate them with my application? I looked into CampFire via LiveHTTPHeaders and Firebug for about 5 minutes, and it appears to use Ajax to send a request which is never answered until another chat happens. Is this just CampFire opening a new thread on the server to listen for an update and then returning a response to the request when the thread hears an update? I noticed that they're requesting on a specific port (8043 if memory serves me) which makes me think that they're doing something more complex than just what I mentioned. Also, the URL requested started with /tcp/ which I found interesting. Note: I don't expect to ever have more than 150 users live-chatting in all the rooms combined at the same time. I understand that if I was building a hosted pay for chat service like CampFire with thousands of concurrent users, it would behoove me to invest time in researching special technologies vs trying to reinvent the wheel in a simple way in my app. Also, if you're going to do it with server polling, how often would you personally poll to maximize response without slamming the server?

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  • Good guidelines for developing an ecommerce application

    - by kaciula
    I'm making an ecommerce application on Android and, as it is my first serious project, I'm trying to figure out beforehand the best approach to do this. The application talks to a web service (magento api, meaning soap or xml rpc unfortunately) and gets all the content on the phone (product categories, product details, user credentials etc.). I think it should do lazy loading or something like that. So, I was thinking to keep the user credentials in a custom Object which will be kept in a SharedPreferences so that every Activity cand easily access it. I'll use a couple of ListViews to show the content and AsyncTask to fetch the data needed. Should I keep all the data in memory in objects or should I use some sort of cache or a local database? Also, I'm planning to use a HashMap with SoftReferences to hold the bitmaps I am downloading. But wouldn't this eat a lot of memory? How cand all the activities have access to all these objects (ecommerce basket etc.)? I'm thinking of passing them using Intents but this doesn't seem right to me. Can SharedPreferences be used for a lot of objects and are there any concurrency issues? Any pointers would be really appreciated. What are some good guidelines? What classes should I look into? Do you know of any resources on the Internet for me to check out?

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  • Bespoke Development or Leverage SharePoint With Web Parts etc?

    - by Asim
    Hi all, We are currently in the process of drawing up a solution for an existing client, creating a number of eServices. The client currently have MOSS 2007. The proposed solution is to use MOSS as the launching pad for the eServices… The requirement involves drawing up several online forms which provide registration facilities as well as facilitating a workflow of some sort. I have been told that the proposed solution requires complex web forms. Most are complex forms with parent child details that have multiple windows. The proposed solution is to do some bespoke development, developing ASP .NET forms. These forms would be deployed under the _layouts folder of the current MOSS portal, inheriting the master page design on the current site. I have been told that this approach make development and deployment more simple, as well has having ‘complete integration’ with MOSS. My questions are: Is this the best way to leverage SharePoint – it seems like the proposed solution is not leveraging MOSS at all..! I thought perhaps utilizing Web Parts would be better, but I have been told that this is more complex and developing more smarter intuitive UI is more difficult. Is this really the case? If not, what should be the recommended approach? We will be utilizing Ultimus as the workflow engine. However, I have been recommended K2 Workflows. Anyone used both/have any opinions on either? Many thanks in advance! Kind Regards,

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  • How to make active services highly available?

    - by Jader Dias
    I know that with Network Load Balancing and Failover Clusteringwe can make passive services highly available. But what about active apps? Example: One of my apps retrieves some content from a external resource in a fixed interval. I have imagined the following scenarios: Run it in a single machine. Problem: if this instance falls, the content won't be retrieved Run it in each machine of the cluster. Problem: the content will be retrieved multiple times Have it in each machine of the cluster, but run it only in one of them. Each instance will have to check some sort of common resource to decide whether it its turn to do the task or not. When I was thinking about the solution #3 I have wondered what should be the common resource. I have thought of creating a table in the database, where we could use it to get a global lock. Is this the best solution? How does people usually do this? By the way it's a C# .NET WCF app running on Windows Server 2008

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  • OracleGlobalization.SetThreadInfo() ORA-12705 Error

    - by michele
    Hi guys! I'm stuck in a problem, i cannot workaround! I have a Oracle client 11, with registry key set to AMERICAN_AMERICA.WE8ISO8859P1. I cannot edit this key, but my application must get data from Oracle in Italian culture format. So I want to edit culture info form my application only. I'm trying to using OracleGlobalization class in ODP.NET library before my Application.Run(), to set culture for my thread: OracleGlobalization og = OracleGlobalization.GetThreadInfo(); //OracleGlobalization.SetThreadInfo(OracleGlobalization.GetThreadInfo()); og.Calendar = "GREGORIAN"; og.Comparison = "BINARY"; og.Currency = "€"; og.DateFormat = "DD-MON-RR"; og.DateLanguage = "ITALIAN"; og.DualCurrency = "€"; og.ISOCurrency = "ITALY"; og.Language = "ITALIAN"; og.LengthSemantics = "BYTE"; og.NCharConversionException = false; og.NumericCharacters = ",."; og.Sort = "WEST_EUROPEAN"; og.Territory = "ITALY"; OracleGlobalization.SetThreadInfo(og); I get always the same error: ORA-12705: Cannot access NLS data files or invalid environment specified. I really don't know ho to solve this problem! Any hint? I'm working on a Win7 pc with VisualStudio 2008. Thank you in advance!

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  • Trying to find a PHP5 API-based embeddable CMS

    - by StrangeElement
    I've been making the rounds for a CMS that I can use as an API, in a sort of "embedded" mode. I mean by this that I don't want the CMS to do any logic or presentation. I want it to be used as an API, which I can then use within an existing site. I don't want to be tied to the architecture of the CMS. A good example of this is NC-CMS (http://www.nconsulting.ca/nc-cms/). All it needs is an include at the top, then wherever editable content is desired it's only a function call with a unique label. It's also perfect in the sense that it allows to differentiate between small strings (like titles, labels) and texts (which require a rich-text editor). It's the only CMS I found that fits this description, but it is a little too light as it does not handle site structure. I need to be able to allow my client to add pages, choosing an existing template for the layout. A minimal back-end is required. Wordpress also fits some requirements in that it handles only content editing and allows freedom for the themes by letting them call the content where and how they want it. But it is article-based and backwards, in that it embeds sites (as themes) within its structure, rather than being embeddable in sites like NC. It's funny how checking out all the CMS out there, almost all of them claim that most CMS are not self-sufficient, that they do not handle application logic, while (almost) every single on I found with only one exception do so. Many are mostly article-based blog engines, which does not fit my need. I would appreciate any CMS that fits the general description.

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  • How to build a sequence in the method calls of a fluent interface

    - by silverfighter
    Hi I would like to build a fluent interface for creating am object some sort of factory or builder. I understand that I have to "return this" in order to make the methods chainable. public class CarBuilder { public CarBuilder() { car = new Car(); } private Car car; public CarBuilder AddEngine(IEngineBuilder engine) { car.Engine = engine.Engine(); return this; } public CarBuilder AddWheels(IWheelsBuilder wheels) { car.Wheels = wheels.Wheels(); return this; } public CarBuilder AddFrame(IFrameBuilder frame) { car.Frame = frame.Frame(); return this; } public Car BuildCar() { return car; } } with this I could build a car like that: Car c = builder.AddFrame(fBuilder).AddWheels(wBuilder).AddEngine(eBuilder).BuildCar(); But what I need is a special sequence or workflow: I can only build the wheels on top of the frame and when the wheels exist then I'll be able to build up the engine. So instead of offering every method of the car builder I want to be able to add only the frame to the builder and then only the wheels to the frame and then the engine on top of that... And how would it be or what would be a good implementation if the EngineBuilder itself has a fluent api like eBuilder.Cylinders(12).WithPistons().... Would it be possible to have something like this Car c = builder.AddFrame(fBuilder).AddWheels(wBuilder).AddEngine(x=>x.WithCylinders(12).WithPistons()).BuildCar(); So in sum how to structure the flow of the fluent interface and how to nest fluent Interfaces?

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  • Why does Tex/Latex not speed up in subsequent runs?

    - by Debilski
    I really wonder, why even recent systems of Tex/Latex do not use any caching to speed up later runs. Every time that I fix a single comma*, calling Latex costs me about the same amount of time, because it needs to load and convert every single picture file. (* I know that even changing a tiny comma could affect the whole structure but of course, a well-written cache format could see the impact of that. Also, there might be situations where 100% correctness is not needed as long as it’s fast.) Is there something in the language of Tex which makes this complicated or impossible to accomplish or is it just that in the original implementation of Tex, there was no need for this (because it would have been slow anyway on those large computers)? But then on the other hand, why doesn’t this annoy other people so much that they’ve started a fork which has some sort of caching (or transparent conversion of Tex files to a format which is faster to parse)? Is there anything I can do to speed up subsequent runs of Latex? Except from putting all the stuff into chapterXX.tex files and then commenting them out?

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  • Formatting Parameters for Ajax POST request to Rails Controller - for jQuery-UI sortable list

    - by Hung Luu
    I'm using the jQuery-UI Sortable Connected Lists. I'm saving the order of the connected lists to a Rails server. My approach is to grab the list ID, column ID and index position of each list item. I want to then wrap this into an object that can be passed as a parameter back to the Rails Controller to be saved into the database. So ideally i'm looking to format the parameter like this: Parameters: {"Activity"=>[{id:1,column:2,position:1},{id:2,column:2,position:2} ,...]} How do I properly format my parameters to be passed in this Ajax POST request? Right now, with the approach below, I'm passing on Parameters: {"undefined"=>""} This is my current jQuery code (Coffeescript) which doesn't work: jQuery -> $('[id*="day"]').sortable( connectWith: ".day" placeholder: "ui-state-highlight" update: (event, ui) -> neworder = new Array() $('[id*="day"] > li').each -> column = $(this).attr("id") index = ui.item.index() + 1 id = $("#" + column + " li:nth-child(" + index + ") ").attr('id') passObject={} passObject.id = id passObject.column = column passObject.index = index neworder.push(passObject) alert neworder $.ajax url: "sort" type: "POST" data: neworder ).disableSelection() My apologies because this seems like a really amateur question but I'm just getting started with programming jQuery and Javascript.

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  • Spring 3.0 vs J2EE 6.0

    - by StudiousJoseph
    Hi everybody, I'm confronted with a situation... I've been asked to give an advise regarding which approach to take, in terms of J2EE development between Spring 3.0 and J2EE 6.0. I was, and still am, a promoter of Spring 2.5 over classic J2EE 5 development, specially with JBoss, I even migrated old apps to Spring and influenced the re-definition of the development policy here to include Spring specific APIs, and helped the development of a strategic plan to foster more lightweight solutions like Spring + Tomcat, instead of the heavier ones of JBoss, right now, we're using JBoss merely as a Web container, having what i call the "container inside the container paradox", that is, having Spring apps, with most of its APIs, running inside JBoss, So we're in the process of migrating to tomcat. However, with the coming of J2EE 6.0 many features, that made Spring attractive at that time, easy deployment, less-coupling, even some sort of D.I, etc, seems to have been mimicked, in one way or the other. JSF 2.0, JPA 2.0, WebBeans, WebProfiles, etc. So, the question goes... From your point of view, how save, and logical, it is to continue to invest in a non-standard J2EE development framework like Spring given the new perspectives offered by J2EE 6.0? Can we talk about maybe 3 or 4 more years of Spring development, or do you recommend early adoption of J2EE 6.0 APIs and it's practices? I'll appreciate any insights with this...

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  • Managing aesthetic code changes in git

    - by Ollie Saunders
    I find that I make a lot of small changes to my source code, often things that have almost no functional effect. For example: Refining or correcting comments. Moving function definitions within a class for a more natural reading order. Spacing and lining up some declarations for readability. Collapsing something using multiple lines on to one. Removing an old piece of commented-out code. Correcting some inconsistent whitespace. I guess I have a formidable attention to detail in my code. But the problem is I don't know what to do about these changes and they make it difficult to switch between branches etc. in git. I find myself not knowing whether to commit the minor changes, stash them, or put them in a separate branch of little tweaks and merge that in later. None those options seems ideal. The main problem is that these sort of changes are unpredictable. If I was to commit these there would be so many commits with the message "Minor code aesthetic change.", because, the second I make such a commit I notice another similar issue. What should I do when I make a minor change, a significant change, and then another minor change? I'd like to merge the three minor changes into one commit. It's also annoying seeing files as modified in git status when the change barely warrants my attention. I know about git commit --amend but I also know that's bad practice as it makes my repo inconsistent with remotes.

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  • Getting my head around object oriented programing

    - by nLL
    I am entry level .Net developer and using it to develop web sites. I started with classic asp and last year jumped on the ship with a short C# book. As I developed I learned more and started to see that coming from classic asp I always used C# like scripting language. For example in my last project I needed to encode video on the webserver and wrote a code like public class Encoder { Public static bool Encode(string videopath) { ...snip... return true; } } While searching samples related to my project I’ve seen people doing this public class Encoder { Public static Encode(string videopath) { EncodedVideo encoded = new EncodedVideo(); ...snip... encoded.EncodedVideoPath = outputFile; encoded.Success = true; ...snip... } } public class EncodedVideo { public string EncodedVideoPath { get; set; } public bool Success { get; set; } } As I understand second example is more object oriented but I don’t see the point of using EncodedVideo object. Am I doing something wrong? Does it really necessary to use this sort of code in a web app?

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  • How to implement generic callbacks in C++

    - by Kylotan
    Forgive my ignorance in asking this basic question but I've become so used to using Python where this sort of thing is trivial that I've completely forgotten how I would attempt this in C++. I want to be able to pass a callback to a function that performs a slow process in the background, and have it called later when the process is complete. This callback could be a free function, a static function, or a member function. I'd also like to be able to inject some arbitrary arguments in there for context. (ie. Implementing a very poor man's coroutine, in a way.) On top of that, this function will always take a std::string, which is the output of the process. I don't mind if the position of this argument in the final callback parameter list is fixed. I get the feeling that the answer will involve boost::bind and boost::function but I can't work out the precise invocations that would be necessary in order to create arbitrary callables (while currying them to just take a single string), store them in the background process, and invoke the callable correctly with the string parameter.

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  • Creating Emulated iSCSI Target in a Lab/Testing Environment using Windows Server 2008 R2

    - by Brian McCleary
    We have a single server running Windows Server 2008 with Hyper-V installed running 5 virtual machines. I have purchased a second DELL R805 Server so that we can create a fail-over cluster to our current R805 that is currently in production. Right now, our R805 connects via iSCSI to a MD3000i iSCSI SAN. Before we try to roll out the second server and clustering to our production environment, I want to be able to test and "play with" the clustering features in our lab before rolling it out. The problem is that I don't want to spend a couple thousand dollars on another iSCSI SAN server just for testing. I already have two servers in my lab that are installed with Windows Server 2008 R2 64bit (one is the R805 and another spare desktop that was laying around) and with the Hyper-V roll enabled that should be ready to test with, but I don't have an iSCSI target to use as the Cluster Shared Volume. Is there anyway to install, either on a Hyper-V image or on a external spare computer that we have some sort of emulated iSCSI target? In our lab, we obviously don't need a real SAN, just something that we can test out how to setup the clustering properly outside of our production environment. Any advise is appreciated. FYI - I have read Jose Barret's blog on WUDSS at http://blogs.technet.com/josebda/archive/2008/01/07/installing-the-evaluation-version-of-wudss-2003-refresh-and-the-microsoft-iscsi-software-target-version-3-1-on-a-vm.aspx, but it seems awfully complex. I'm hoping for an easier solution.

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  • Suggestions on implementing an iPad magazine app

    - by alku83
    I've been tasked with creating a magazine style app for iPad. Ideally it would look a little something like the Zinio app: http://www.zinio.com/ipad/ . This app is effectively a shell, allowing you to sample magazines (eg. read the first few pages) and select them for download. The magazines appear to have some sort of overlay, allowing you to interact with some things (eg. tap to watch a video). A few questions that come to mind: How would I go about delivering content to the user? In-app purchases aren't really an option, as some content will need to be delivered for free. Is it possible to download a package and make this available within the application? What format would be suitable for displaying the magazine? Sequential images, PDF, ebook? I'll need to have some form of interactivity. I guess I could have some form of lookup table, which would include information such as if the user taps on this page, within these coordinates, then launch this item. Anyone dealt with any similar issues?

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  • Import-Pssession is not importing cmdlets when used in a custom module

    - by Douglas Plumley
    I have a PowerShell script/function that works great when I use it in my PowerShell profile or manually copy/paste the function in the PowerShell window. I'm trying to make the function accessible to other members of my team as a module. I want to have the module stored in a central place so we can all add it to our PSModulePath. Here is a copy of the basic function: Function Connect-O365{ $o365cred = Get-Credential [email protected] $session365 = New-PSSession -ConfigurationName Microsoft.Exchange -ConnectionUri https://ps.outlook.com/powershell/ -Credential $o365cred -Authentication Basic -AllowRedirection Import-PSSession $session365 -AllowClobber } If I save this function in my PowerShell profile it works fine. I can dot source a *.ps1 script with this function in it and it works as well. The issue is when I save the function as a *.psm1 PowerShell script module. The function runs fine but none of the exported commands from the Import-PSSession are available. I think this may have something to do with the module scope. I'm looking for suggestions on how to get around this. EDIT When I create the following module and run Connect-O365 the imported cmdlets will not be available. $scriptblock = { Function Connect-O365{ $o365cred = Get-Credential [email protected] $session365 = New-PSSession -ConfigurationName Microsoft.Exchange -ConnectionUri "https://ps.outlook.com/powershell/" -Credential $o365cred -Authentication Basic -AllowRedirection Import-PSSession $session365 -AllowClobber } } New-Module -Name "Office 365" -ScriptBlock $scriptblock When I import the next module without the Connect-O365 function the imported cmdlets are available. $scriptblock = { $o365cred = Get-Credential [email protected] $session365 = New-PSSession -ConfigurationName Microsoft.Exchange -ConnectionUri "https://ps.outlook.com/powershell/" -Credential $o365cred -Authentication Basic -AllowRedirection Import-PSSession $session365 -AllowClobber } New-Module -Name "Office 365" -ScriptBlock $scriptblock This appears to be a scope issue of some sort, just not sure how to get around it.

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  • Sorting a list in PHP

    - by Andy
    Alright, so I've just (almost) finished my first little php script. Basically all it does is handling forms. It writes whatever the user put in to the fields of the form to a text file, then I include that text file in the index of the little page I have set up. So, currently it writes to the beginning of the text file (but doesn't overwrite previous data). But, several users wants this list to be alphabetically sorted instead. So what I want to do is make whatever they submit fall into the list in alphabetical order. The thing here is also that all I use in the text file are divs. The list is basically 'divided' into 3 parts. 'Title', 'Link', and 'Poster'. All I have done is positioned them with css. So, can I sort this list (the titles, in this case) alphabetically and still have the 'link' and 'poster' information assigned the way they already are, but just with the titles sorted? It don't use databases at all on my site, so there is no database handling at all used in this script (mainly because I'm not experienced at all in this).

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  • heterogeneous comparisons in python3

    - by Matt Anderson
    I'm 99+% still using python 2.x, but I'm trying to think ahead to the day when I switch. So, I know that using comparison operators (less/greater than, or equal to) on heterogeneous types that don't have a natural ordering is no longer supported in python3.x -- instead of some consistent (but arbitrary) result we raise TypeError instead. I see the logic in that, and even mostly think its a good thing. Consistency and refusing to guess is a virtue. But what if you essentially want the python2.x behavior? What's the best way to go about getting it? For fun (more or less) I was recently implementing a Skip List, a data structure that keeps its elements sorted. I wanted to use heterogeneous types as keys in the data structure, and I've got to compare keys to one another as I walk the data structure. The python2.x way of comparing makes this really convenient -- you get an understandable ordering amongst elements that have a natural ordering, and some ordering amongst those that don't. Consistently using a sort/comparison key like (type(obj).__name__, obj) has the disadvantage of not interleaving the objects that do have a natural ordering; you get all your floats clustered together before your ints, and your str-derived class separates from your strs. I came up with the following: import operator def hetero_sort_key(obj): cls = type(obj) return (cls.__name__+'_'+cls.__module__, obj) def make_hetero_comparitor(fn): def comparator(a, b): try: return fn(a, b) except TypeError: return fn(hetero_sort_key(a), hetero_sort_key(b)) return comparator hetero_lt = make_hetero_comparitor(operator.lt) hetero_gt = make_hetero_comparitor(operator.gt) hetero_le = make_hetero_comparitor(operator.le) hetero_ge = make_hetero_comparitor(operator.gt) Is there a better way? I suspect one could construct a corner case that this would screw up -- a situation where you can compare type A to B and type A to C, but where B and C raise TypeError when compared, and you can end up with something illogical like a > b, a < c, and yet b > c (because of how their class names sorted). I don't know how likely it is that you'd run into this in practice.

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  • How to control the order of module initialization in Prism

    - by Robert Taylor
    I'm using Prism V2 with a DirectoryModuleCatalog and I need the modules to be initialized in a certain order. The desired order is specified with an attribute on each IModule implementation. This is so that as each module is initialized, they add their View into a TabControl region and the order of the tabs needs to be deterministic and controlled by the module author. The order does not imply a dependency, but rather just an order that they should be initialized in. In other words: modules A, B, and C may have priorities of 1, 2, and 3 respectively. B does not have a dependency on A - it just needs to get loaded into the TabControl region after A. So that we have a deterministic and controllable order of the tabs. Also, B might not exist at runtime; so they would load as A, C because the priority should determine the order (1, 3). If i used the ModuleDependency, then module "C" will not be able to load w/o all of it's dependencies. I can manage the logic of how to sort the modules, but i can't figure out where to put said logic.

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  • iPhone: Leak with UIWebView loading Office documents. Any ideas how to avoid it?

    - by Thomas Tempelmann
    While there are already quite a few posts about leaks around UIWebView, mine is a bit more special, I believe, and thus deserves its own post here. I see a reproducible large leak every time I load a Office document such as a Word or Excel file. For instance, every time I display a 180KB .doc file, I get a 100KB leak. And that happens with both the simulator and an actual device, running OS 3.1.3. The leak is not visible with the Leaks instrument but only by looking at the malloc instances via the ObjectAlloc instrument. Here's a picture from the instruments trace: I've also made a demo project, UIWebView-Leak.zip, so you can verify this yourself. To see the leak, use the ObjectAlloc instrument, switch to the view where you see individual allocation objects, and sort by size so that you see the large ones in a group, just like in my picture above. Then view a Office document a few times and find the Malloc objects that keep staying "Live" even after the actual UIWebView has been freed. Is this a known bug? Or is there any way I can avoid these leaks? I.e, have you successfully shown Office documents on an iPhone withing getting such leaks? Note: I've reported this as a bug to Apple now, too (ID 7950594) I am still waiting for someone (including Apple) to confirm this as a true leak or show why it isn't (i.e. that I do something wrong or make wrong assumptions)

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  • Why doesn't C# do "simple" type inference on generics?

    - by Ken Birman
    Just curious: sure, we all know that the general case of type inference for generics is undecidable. And so C# won't do any kind of subtyping at all: if Foo<T> is a generic, Foo<int> isn't a subtype of Foo<T>, or Foo<Object> or of anything else you might cook up. And sure, we all hack around this with ugly interface or abstract class definitions. But... if you can't beat the general problem, why not just limit the solution to cases that are easy. For example, in my list above, it is OBVIOUS that Foo<int> is a subtype of Foo<T> and it would be trivial to check. Same for checking against Foo<Object>. So is there some other deep horror that would creep forth from the abyss if they were to just say, aw shucks, we'll do what we can? Or is this just some sort of religious purity on the part of the language guys at Microsoft?

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  • Float addition promoted to double?

    - by Andreas Brinck
    I had a small WTF moment this morning. Ths WTF can be summarized with this: float x = 0.2f; float y = 0.1f; float z = x + y; assert(z == x + y); //This assert is triggered! (Atleast with visual studio 2008) The reason seems to be that the expression x + y is promoted to double and compared with the truncated version in z. (If i change z to double the assert isn't triggered). I can see that for precision reasons it would make sense to perform all floating point arithmetics in double precision before converting the result to single precision. I found the following paragraph in the standard (which I guess I sort of already knew, but not in this context): 4.6.1. "An rvalue of type float can be converted to an rvalue of type double. The value is unchanged" My question is, is x + y guaranteed to be promoted to double or is at the compiler's discretion? UPDATE: Since many people has claimed that one shouldn't use == for floating point, I just wanted to state that in the specific case I'm working with, an exact comparison is justified. Floating point comparision is tricky, here's an interesting link on the subject which I think hasn't been mentioned.

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  • OOP - Handling Automated Instances of a Class - PHP

    - by dscher
    This is a topic that, as a beginner to PHP and programming, sort of perplexes me. I'm building a stockmarket website and want users to add their own stocks. I can clearly see the benefit of having each stock be a class instance with all the methods of a class. What I am stumped on is the best way to give that instance a name when I instantiate it. If I have: class Stock() { ....doing stuff..... } what is the best way to give my instances of it a name. Obviously I can write: $newStock = new Stock(); $newStock.getPrice(); or whatever, but if a user adds a stock via the app, where can the name of that instance come from? I guess that there is little harm in always creating a new child with $newStock = new Stock() and then storing that to the DB which leads me to my next question! What would be the best way to retrieve 20 user stocks(for example) into instances of class Stock()? Do I need to instantiate 20 new instances of class Stock() every time the user logs in or is there something I'm missing? I hope someone answers this and more important hope a bunch of people answer this and it somehow helps someone else who is having a hard time wrapping their head around what probably leads to a really elegant solution. Thanks guys!

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  • How do I send text to a UITextView?

    - by Lee
    I'm new to iphone development. I'm a VB programmer who is trying to convert a VB application to an ipad app. I need some help with sending text to a UITextView. I want to first have a UIPickerView and then once the user hits a UIButton, a UITextView appears and the text is then generated by my source code code, line by line. The code would constantly be concatenating strings to the text. It would sort of go like this-- 1) User makes selections with UIPickerView. 2) User then hits UIButton. 3) UIPickerView is replaced on the screen with a UITextView. 4) The code does stuff. 5) The code adds the 1st line of text into the UITextView. 6) The code does more stuff. 7) The code then adds the 2nd line of text into the UITextView, retaining the 1st line that was already there. Steps 6 and 7 are repeated until the code is done. Does anyone know of any examples of this that I could look at? I am mostly interested in finding something like a youtube video, a webpage that explains the code or even a good book that covers this particular topic. I am finding that the sample codes that Apple has on this site goes over my head. In fact, I could probably benefit from a good book. But, I am looking for one that I would already know covers this particular topic, since it is so essential to the app that I am trying to build.

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  • Problem with sorting NSDictionary

    - by Stas Dmitrenko
    Hello. I need to sort a NSDictionary of dictionaries. It looks like: {//dictionary RU = "110.1"; //key and value SG = "150.2"; //key and value US = "50.3"; //key and value } Result need to be like: {//dictionary SG = "150.2"; //key and value RU = "110.1"; //key and value US = "50.3"; //key and value } I am trying this: @implementation NSMutableDictionary (sorting) -(NSMutableDictionary*)sortDictionary { NSArray *allKeys = [self allKeys]; NSMutableArray *allValues = [NSMutableArray array]; NSMutableArray *sortValues= [NSMutableArray array]; NSMutableArray *sortKeys= [NSMutableArray array]; for(int i=0;i<[[self allValues] count];i++) { [allValues addObject:[NSNumber numberWithFloat:[[[self allValues] objectAtIndex:i] floatValue]]]; } [sortValues addObjectsFromArray:allValues]; [sortKeys addObjectsFromArray:[self allKeys]]; [sortValues sortUsingDescriptors:[NSArray arrayWithObject:[[[NSSortDescriptor alloc] initWithKey:@"floatValue" ascending:NO] autorelease]]]; for(int i=0;i<[sortValues count];i++) { [sortKeys replaceObjectAtIndex:i withObject:[allKeys objectAtIndex:[allValues indexOfObject:[sortValues objectAtIndex:i]]]]; [allValues replaceObjectAtIndex:[allValues indexOfObject:[sortValues objectAtIndex:i]] withObject:[NSNull null]]; } NSLog(@"%@", sortKeys); NSLog(@"%@", sortValues); NSLog(@"%@", [NSMutableDictionary dictionaryWithObjects:sortValues forKeys:sortKeys]); return [NSMutableDictionary dictionaryWithObjects:sortValues forKeys:sortKeys]; } @end This is the result of NSLog: 1) { SG, RU, US } 2) { 150.2, 110.1, 50.3 } 3) { RU = "110.1"; SG = "150.2"; US = "50.3"; } Why is this happening? Can you help me with this problem?

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