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  • Run code before class instanciation in ActionScript 3

    - by soow.fr
    I need to run code in a class declaration before its instanciation. This would be especially useful to automatically register classes in a factory. See: // Main.as public class Main extends Sprite { public function Main() : void { var o : Object = Factory.make(42); } } // Factory.as public class Factory { private static var _factory : Array = new Array(); public static function registerClass(id : uint, c : Class) : void { _factory[id] = function () : Object { return new c(); }; } public static function make(id : uint) : Object { return _factory[id](); } } // Foo.as public class Foo { // Run this code before instanciating Foo! Factory.registerClass(42, Foo); } AFAIK, the JIT machine for the ActionScript language won't let me do that since no reference to Foo is made in the Main method. The Foo class being generated, I can't (and don't want to) register the classes in Main: I'd like to register all the exported classes in a specific package (or library). Ideally, this would be done through package introspection, which doesn't exist in ActionScript 3. Do you know any fix (or other solution) to my design issue?

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  • Avoiding resource (localizable string) duplication with String.Format

    - by Hrvoje Prgeša
    I'm working on a application (.NET, but not relevant) where there is large potential for resource/string duplication - most of these strings are simple like: Volume: 33 Volume: 33 (dB) Volume 33 dB Volume (dB) Command - Volume: 33 (dB) where X, Y and unit are the same. Should I define a new resource for each of the string or is it preferable to use String.Format to simplify some of these, eg.: String.Format("{0}: {1}", Resource.Volume, 33) String.Format("{0}: {1} {2}", Resource.Volume, 33, Resource.dB) Resource.Volume String.Format("{0} ({1})", 33, Resource.dB) String.Format("{0} ({1})", Resource.Volume, Resource.dB) String.Format("Command - {0}: {1} {2}", Resource.Volume, 33, Resource.dB) I would also define string formats like "{0}: {1}" in the resources so there would be a possibility of reordering words... I would not use this approach selectivly and not throughout the whole application.. And how about: String.Format("{0}: {1}", Volume, Resource.Muted_Volume) // = Volume: Muted Resource.Muted_Volume String.Format("{0}: {1} (by user {2})", Volume, Resource.Muted_Volume, "xy") // = Volume: Muted (by user xy) The advantage is cutting the number of resource by the factor of 4-5. Are there any hidden dangers of using this approach? Could someone give me an example (language) where this would not work correctly?

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  • Why is my JavaScript function "a" not defined?

    - by 4l3x
    When I call my JavaScript function B, the javascript console in firefox said that function A is not defined, but on chrome browser if defined. And when I call function "A" in body segment: <input type="button" onclick="A()" value=" ..A.. "> , firefox said that function B is not defined? :S <html> <head> <script language="javascript" type="text/javascript"> function B(){ alert(" hi B "); document.write('<br><br><input type="button" onClick="A()" value=" ..A..">'); }; function A(){ alert(" hi A"); document.write('<br><br><input type="button" onclick="B()" value=" ..b..">'); if (window.WebCL == undefined) { alert("Unfortunately your system does not support WebCL. "); return false; } } </script> </head> <body> <input type="button" onclick="B()" value=" ..B.. "> </body> </html>

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  • Error in FireFox Loading Images

    - by Brian
    Hello, Details of the app are: ASP.NET project, local web server, hosted in IIS locally, using latest FireFox, uses forms authentication. I'm getting a logon user name/pwd box when trying to access my local web server. Using the net panel in firebug, I see the issue is with an animated GIF, showing up as 401 unauthorized. I check the details and this is what I see for this URL: http://localhost/<virtual>/Images/loading.gif I'm getting the following: Response Headers: Server Microsoft-IIS/5.1 Date Thu, 17 Jun 2010 19:02:58 GMT WWW-Authenticate Negotiate NTLM Connection close Content-Length 4046 Content-Type text/html Request headers: Host localhost User-Agent Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2.3) Gecko/20100401 Firefox/3.6.3 ( .NET CLR 3.5.30729; .NET4.0E) Accept image/png,image/*;q=0.8,*/*;q=0.5 Accept-Language en-us,en;q=0.5 Accept-Encoding gzip,deflate Accept-Charset ISO-8859-1,utf-8;q=0.7,*;q=0.7 Keep-Alive 115 Connection keep-alive Referer <correct referer> Cookie ASP.NET_SessionId=ux4bt345qjz4p3u1wm1zgmez; .ASPXFormsAuth=33F12B444040827B8ABF154EE4EDE43B6CA532432EB846987B355097E00256DF0955C76A37BC593EAA961747BF1CC1D8949FF63C6F2CA69D77213EB15B4EDFAF57A83D9E1F88AB8D821C3A09C07EA2EE; .ASPROLES=qTFrGteJydYAE3118WGXbhJthTDdjdtuQ06t4bYVrM1BwIfcEHU1HhnEcs7TqSOaV-fIN5MH3uO57oNVWXDvrhkZ8gQuURuUk_K0TpoR-DEFXuF953Gl9aIilKAdV211jutMNQmhkt2rdPE2tEhHs3pz953fADxjAOyZl7K-AqNvMk3yqJshhKHhJIf-ALMhWIYlrrKy0WsYznUwh3WCtPfzEBD5XzmXU8HVMJ2-ArLjBISuegvSmxvK1PuXBPhoMRMi9Ynaw6xi9ypGk-R6uN0ljOMCGkB2-20WUlFuP0xWTfac_zCTDT00pbpnyjtygnM-LShOXTrZ_mhoRuXfKYEYSodNihwD6SRr19Nm-8uZ5BQ-W81svM17S2C0vc0FaxtiuAcN_vHcsN1OEJeCuVfRjeqzo9xWEViupP3Vh6aOcCm6yrftgw5x94piuCJO7tCfXjJAw5RVUWDBBWv5gmid171F0k-_XZ0CSv7Gm2Eai1BRfogAqQ_MV3tyPv7XVEyJXRXqYGlf1JpkfTW8S8On4E05v9gx9RcdnKHZebiOZwbP1_ho9nG7pMwXysbhjxtxwZ-zLx-v11_rhZw_i5m7iNcLtt4BbFU-sb_crzMpCKGywHIc452Zp1E0kx1Rfx-2eUnaiLiCfGed-QqelO88NYTpJHttGKEfhFrDgmaIXZPJRtuZ-GrS6t3Vla-8qDAVb1p6ovPwoVT4z4BhQyFsk542gDx-uQDw6D0B6zo7lXfcOjtolUxDcLbETsNlYsexZaxFpRSbw7M1ldwL_k92P9wLPlv9mw4NtyhXKJesMu7GjquZuoBN3hO00AqJEe1tKFFtfrvbE5ZH7uNu7myNdtlxRPe3WZe7qukbqHo1 Pragma no-cache Cache-Control no-cache Any ideas? Thanks.

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  • perl - universal operator overload

    - by Todd Freed
    I have an idea for perl, and I'm trying to figure out the best way to implement it. The idea is to have new versions of every operator which consider the undefined value as the identity of that operation. For example: $a = undef + 5; # undef treated as 0, so $a = 5 $a = undef . "foo"; # undef treated as '', so $a = foo $a = undef && 1; # undef treated as false, $a = true and so forth. ideally, this would be in the language as a pragma, or something. use operators::awesome; However, I would be satisfied if I could implement this special logic myself, and then invoke it where needed: use My::Operators; The problem is that if I say "use overload" inside My::Operators only affects objects blessed into My::Operators. So the question is: is there a way (with "use overoad" or otherwise) to do a "universal operator overload" - which would be called for all operations, not just operations on blessed scalars. If not - who thinks this would be a great idea !? It would save me a TON of this kind of code if($object && $object{value} && $object{value} == 15) replace with if($object{value} == 15) ## the special "is-equal-to" operator

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  • jQuery draggable removing without changing position of other elements

    - by Yurish
    Hi! I am building a page layout configuration system on jQuery. So everyone, who is using my website can make it personal by moving elements on webpage. But, I have a problem. Every element on my page is a draggable div with option to be removed from page if necessary. When user wants to remove an element, he clicks on inner div and the following function is called: <script language="javascript"> $(function() { $('.close').click(function(){ $(this).parent().hide(); }); }); </script> <div class="main"><div class="close"></div></div> When user wants to add an element on page, he clicks on link and followinf function is called: function addNewWidget(page_name, size){ var page = $('#'+page_name); var closeDiv = $(document.createElement("div")).attr("class", "close").html('X'); closeDiv.click(function(){ $(this).parent().hide(); }); var div = $(document.createElement("div")) div.attr("class", "drag"); div.appendTo(page); closeDiv.appendTo(div); div.draggable({ containment: "#page", scroll: false, grid: [200, 200] }); div.css("top:0; left:0"); div.addClass(size); div.addClass('widget'); } Everything works fine, but when element is removed, other elements, which were on page are moving up. It is because of element positioning in the code. These divs in the code are before div, which was removed, and their absolute top is changed by -heghtOfRemovedElement Is there any way to prevent other elements from moving up?

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  • facebook Hacker cup: studious Student problem.

    - by smartmuki
    During the qualification round, the following question was asked: You've been given a list of words to study and memorize. Being a diligent student of language and the arts, you've decided to not study them at all and instead make up pointless games based on them. One game you've come up with is to see how you can concatenate the words to generate the lexicographically lowest possible string. Input As input for playing this game you will receive a text file containing an integer N, the number of word sets you need to play your game against. This will be followed by N word sets, each starting with an integer M, the number of words in the set, followed by M words. All tokens in the input will be separated by some whitespace and, aside from N and M, will consist entirely of lowercase letters. Output Your submission should contain the lexicographically shortest strings for each corresponding word set, one per line and in order. Constraints 1 <= N <= 100 1 <= M <= 9 1 <= all word lengths <= 10 Example input 5 6 facebook hacker cup for studious students 5 k duz q rc lvraw 5 mybea zdr yubx xe dyroiy 5 jibw ji jp bw jibw 5 uiuy hopji li j dcyi Example output cupfacebookforhackerstudentsstudious duzklvrawqrc dyroiymybeaxeyubxzdr bwjibwjibwjijp dcyihopjijliuiuy The program I wrote goes as: chomp($numberElements=<STDIN>); for(my $i=0; $i < $numberElements; $i++) { my $string; chomp ($string = <STDIN>); my @array=split(/\s+/,$string); my $number=shift @array; @sorted=sort @array; $sortedStr=join("",@sorted); push(@data,$sortedStr); } foreach (@data) { print "$_\n"; } The program gives the correct output for the given test cases but still facebook shows it to be incorrect. Is there something wrong with the program??

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  • Android - Parsing XML with XPath

    - by Ruben Deig Ramos
    First of all, thanks to all the people who's going to spend a little time on this question. Second, sorry for my english (not my first language! :D). Well, here is my problem. I'm learning Android and I'm making an app which uses a XML file to store some info. I have no problem creating the file, but trying to read de XML tags with XPath (DOM, XMLPullParser, etc. only gave me problems) I've been able to read, at least, the first one. Let's see the code. Here is the XML file the app generates: <dispositivo> <id>111</id> <nombre>Name</nombre> <intervalo>300</intervalo> </dispositivo> And here is the function which reads the XML file: private void leerXML() { try { XPathFactory factory=XPathFactory.newInstance(); XPath xPath=factory.newXPath(); // Introducimos XML en memoria File xmlDocument = new File("/data/data/com.example.gps/files/devloc_cfg.xml"); InputSource inputSource = new InputSource(new FileInputStream(xmlDocument)); // Definimos expresiones para encontrar valor. XPathExpression tag_id = xPath.compile("/dispositivo/id"); String valor_id = tag_id.evaluate(inputSource); id=valor_id; XPathExpression tag_nombre = xPath.compile("/dispositivo/nombre"); String valor_nombre = tag_nombre.evaluate(inputSource); nombre=valor_nombre; } catch (Exception e) { e.printStackTrace(); } } The app gets correctly the id value and shows it on the screen ("id" and "nombre" variables are assigned to a TextView each one), but the "nombre" is not working. What should I change? :) Thanks for all your time and help. This site is quite helpful! PD: I've been searching for a response on the whole site but didn't found any.

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  • why create CLSID_CaptureGraphBuilder2 instance always failed in a machine

    - by Yigang Wu
    It's a real strange issue, the machine information below is from DXDiag. There is no error reported, but create CLSID_CaptureGraphBuilder2 instance always failed in the machine. It's okay to create CLSID_FilterGraph. Before create CLSID_CaptureGraphBuilder2, I have called CoInitialize and created CLSID_FilterGraph. Only this machine has the error, what dll related with this interface or any function needed to call before to make it work? Thanks in advance. System Information Time of this report: 4/24/2010, 09:46:58 Machine name: TURION Operating System: Windows XP Home Edition (5.1, Build 2600) Service Pack 3 (2600.xpsp_sp3_qfe.100216-1510) Language: Japanese (Regional Setting: Japanese) System Manufacturer: To Be Filled By O.E.M. System Model: MS-7145 BIOS: Default System BIOS Processor: AMD Turion(tm) 64 Mobile Technology MT-30, MMX, 3DNow, ~1.6GHz Memory: 768MB RAM Page File: 376MB used, 1401MB available Windows Dir: C:\WINDOWS DirectX Version: DirectX 9.0c (4.09.0000.0904) DX Setup Parameters: Not found DxDiag Version: 5.03.2600.5512 32bit Unicode DxDiag Notes DirectX Files Tab: No problems found. Display Tab 1: No problems found. Sound Tab 1: No problems found. Sound Tab 2: No problems found. Music Tab: No problems found. Input Tab: No problems found. Network Tab: No problems found.

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  • How Best to Replace Ugly Queries and Dynamic PL/SQL with C#?

    - by Mike
    Hi, I write a lot of one-off Oracle SQL queries (in Toad), and sometimes they can get complex, involving lots of unions, joins, and subqueries, and sometimes requiring dynamic SQL. That is, sometimes SQL queries require set based processing along with significant procedural processing. This is what PL/SQL is custom made for, but as a language it does not begin to compare to C#. Now and then I convert a PL/SQL procedure to C#, and am always amazed at how much cleaner and easier to both read and write the C# version is. The C# program might for example construct a SQL query string piece by piece and/or run several queries and process them as needed. The C# version is usually much faster as well, which must mean that I'm not very good at PL/SQL either. I do not currently have access to LINQ. My question is, how best to package all these little C# programs, which are really just mini reports, that is, replacements for ugly SQL queries? Right now I'm actually using NUnit to hold them, and calling each report a [Test], even though they aren't really tests. NUnit just happens to provide a convenient packaging framework.

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  • Computing, storing, and retrieving values to and from an N-Dimensional matrix

    - by Adam S
    This question is probably quite different from what you are used to reading here - I hope it can provide a fun challenge. Essentially I have an algorithm that uses 5(or more) variables to compute a single value, called outcome. Now I have to implement this algorithm on an embedded device which has no memory limitations, but has very harsh processing constraints. Because of this, I would like to run a calculation engine which computes outcome for, say, 20 different values of each variable and stores this information in a file. You may think of this as a 5(or more)-dimensional matrix or 5(or more)-dimensional array, each dimension being 20 entries long. In any modern language, filling this array is as simple as having 5(or more) nested for loops. The tricky part is that I need to dump these values into a file that can then be placed onto the embedded device so that the device can use it as a lookup table. The questions now, are: What format(s) might be acceptable for storing the data? What programs (MATLAB, C#, etc) might be best suited to compute the data? C# must be used to import the data on the device - is this possible given your answer to #1?

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  • In Ruby or Python can the very idea of Class be rewritten?

    - by John Berryman
    Howdy All... first time at stack overflow. I'm looking into using some of the metaprogramming features provided by Ruby or Python, but first I need to know the extent to which they will allow me to extend the language. The main thing I need to be able to do is to rewrite the concept of Class. This doesn't mean that I want to rewrite a specific class during run time, but rather I want to make my own conceptualization of what a Class is. To be a smidge more specific here, I want to make something that is like what people normally call a Class, but I want to follow an "open world" assumption. In the "closed world" of normal Classes, if I declare Poodle to be a subclass of Dog to be a subclass of Animal, then I know that Poodle is not going to also be a type of FurCoat. However, in an open world Class, then the Poodle object I've defined may or may not be and object of type FurCoat and we won't know for sure until I explain that I can wear the poodle. (Poor poodle.) This all has to do with a study I'm doing concerning OWL ontologies. Just so you know, I've tried to find information online, but due to the overloading of terms here I haven't found anything helpful. Super thanks, John

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  • I read 3 pages of a JQuery book and here's my reaction and question

    - by George
    My jQuery reaction to the language's flexible "selectors" is probably rooted in this experience: I once had managed a project where a developer constructed a web page that was used by users to provide very flexible search parameters for a search screen using dynamic sql string building based on the user's specified search parameter. The resulting queries were usually very complicated and involved joins to many tables. One of the options that the user had was to choose from one of 3 an options. Depending on the user's choice for this option, the resulting SQL would need to query a different set of database columns. For example, if choice option "A" were selected, the resulting database columns queried would be prefixed with "A_"; if option "B" were selected, he resulting database columns queried would be prefixed with "B_" and so on. The developer choice to write all the complete SQL assuming that the user selected, for example, option "A" and therefore first constructed SQLs of this type: SQL = "SELECT A_COL1, A_COL2, A_COL3 FROM TABLE ..." and then after constructing one of a million possible variations on the Query From Hell, did something like this: If UserOption = "B" then SQL = SQL.Replace("A_","B_") 'replace everywhere End if He insisted that this was the easiest was to code it, and while I understood that, I was concerned about maintenance of this code. You see, this worked for a while, but as the search options grew and the database columns evolved, the various "REPLACE small substring" with another small substring had unexpected consequences when applied to an evolving database and new search options. My feeling is that code should be written as much as possible such that you can add to it without fear of breaking what is already there. I feel a better approach, though a bit more work, would have been to write a function to return the appropriate target column based on a common set name and the user selected option. OK, so what does this have to do with jQuery selectors? Are the ultra flexible JQuery selectors kind of like perform a "replace all" on a SQL string? Handy as hell but potentially creating a maintenance nightmare?

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  • Help! I'm a Haskell Newbie

    - by Darknight
    I've only just dipped my toe in the world of Haskell as part of my journey of programming enlightenment (moving on from, procedural to OOP to concurrent to now functional). I've been trying an online Haskell Evaluator. However I'm now stuck on a problem: Create a simple function that gives the total sum of an array of numbers. In a procedural language this for me is easy enough (using recursion) (c#) : private int sum(ArrayList x, int i) { if (!(x.Count < i + 1)) { int t = 0; t = x.Item(i); t = sum(x, i + 1) + t; return t; } } All very fine however my failed attempt at Haskell was thus: let sum x = x+sum in map sum [1..10] this resulted in the following error (from that above mentioned website): Occurs check: cannot construct the infinite type: a = a -> t Please bear in mind I've only used Haskell for the last 30 minutes! I'm not looking simply for an answer but a more explanation of it. Thanks in advanced.

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  • Uniquely identify files/folders in NTFS, even after move/rename

    - by Felix Dombek
    I haven't found a backup (synchronization) program which does what I want so I'm thinking about writing my own. What I have now does the following: It goes through the data in the source and for every file which has its archive bit set OR does not exist in the destination, copies it to the destination, overwriting a possibly existing file. When done, it checks for all files in the destination if it exists in the source, and if it doesn't, deletes it. The problem is that if I move or rename a large folder, it first gets copied to the destination even though it is in principle already there, just has a different path. Then the folder which was already there is deleted afterwards. Apart from the unnecessary copying, I frequently run into space problems because my backup drive isn't large enough to hold the original data twice. Is there a way to programmatically identify such moved/renamed files or folders, i.e. by NTFS ID or physical location on media or something else? Are there solutions to this problem? I do not care about the programming language, but hints for doing this with Python, C++, C#, Java or Prolog are appreciated.

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  • Building a survey to put in a WordPress website using Python/Django

    - by chiurox
    So I've been given a task to build a survey to get data regarding time slot preferences of prospective students for a particular course. I know there are really quick solutions to this like Google Forms, SurveyMonkey, but since it's not unusually hard, I want to implement the survey myself in a totally new language as an opportunity to get started with it and also be able to customize and provide dynamic info to the users who are voting. Although I have done some stuff in PHP, C++, javascript, etc, I'm pretty new to Python+Django framework but it's something I've been meaning to get into since a long time ago. Initially, what I want is to make a grid with the days of the week as columns and time-durations as rows. In each cell I want to provide users a way to choose how strong (high/medium/low) their preference for this particular day+time is. I also want to show how many "votes" have already been cast for this particular preference because this will influence a lot in their decisions and as a result make this process easier when we are going to define the classes. I'll probably store the data in MySQL. Could anyone point me to some really good Python+Django tutorials for my particular purpose? Does anyone think I'm wasting my time with this trivial task by choosing new tools and that I should just use something I already know (like PHP) or a free service or plugin for Wordpress? Thanks!

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  • Objective-C Definedness

    - by Dan Ray
    This is an agonizingly rookie question, but here I am learning a new language and framework, and I'm trying to answer the question "What is Truth?" as pertains to Obj-C. I'm trying to lazy-load images across the network. I have a data class called Event that has properties including: @property (nonatomic, retain) UIImage image; @property (nonatomic, retain) UIImage thumbnail; in my AppDelegate, I fetch up a bunch of data about my events (this is an app that shows local arts event listings), and pre-sets each event.image to my default "no-image.png". Then in the UITableViewController where I view these things, I do: if (thisEvent.image == NULL) { NSLog(@"Going for this item's image"); UIImage *tempImage = [UIImage imageWithData:[NSData dataWithContentsOfURL: [NSURL URLWithString: [NSString stringWithFormat: @"http://www.mysite.com/content_elements/%@_image_1.jpg", thisEvent.guid]]]]; thisEvent.image = tempImage; } We never get that NSLog call. Testing thisEvent.image for NULLness isn't the thing. I've tried == nil as well, but that also doesn't work.

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  • Immutability and shared references - how to reconcile?

    - by davetron5000
    Consider this simplified application domain: Criminal Investigative database Person is anyone involved in an investigation Report is a bit of info that is part of an investigation A Report references a primary Person (the subject of an investigation) A Report has accomplices who are secondarily related (and could certainly be primary in other investigations or reports These classes have ids that are used to store them in a database, since their info can change over time (e.g. we might find new aliases for a person, or add persons of interest to a report) If these are stored in some sort of database and I wish to use immutable objects, there seems to be an issue regarding state and referencing. Supposing that I change some meta-data about a Person. Since my Person objects immutable, I might have some code like: class Person( val id:UUID, val aliases:List[String], val reports:List[Report]) { def addAlias(name:String) = new Person(id,name :: aliases,reports) } So that my Person with a new alias becomes a new object, also immutable. If a Report refers to that person, but the alias was changed elsewhere in the system, my Report now refers to the "old" person, i.e. the person without the new alias. Similarly, I might have: class Report(val id:UUID, val content:String) { /** Adding more info to our report */ def updateContent(newContent:String) = new Report(id,newContent) } Since these objects don't know who refers to them, it's not clear to me how to let all the "referrers" know that there is a new object available representing the most recent state. This could be done by having all objects "refresh" from a central data store and all operations that create new, updated, objects store to the central data store, but this feels like a cheesy reimplementation of the underlying language's referencing. i.e. it would be more clear to just make these "secondary storable objects" mutable. So, if I add an alias to a Person, all referrers see the new value without doing anything. How is this dealt with when we want to avoid mutability, or is this a case where immutability is not helpful?

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  • Is it acceptable to wrap PHP library functions solely to change the names?

    - by Carson Myers
    I'm going to be starting a fairly large PHP application this summer, on which I'll be the sole developer (so I don't have any coding conventions to conform to aside from my own). PHP 5.3 is a decent language IMO, despite the stupid namespace token. But one thing that has always bothered me about it is the standard library and its lack of a naming convention. So I'm curious, would it be seriously bad practice to wrap some of the most common standard library functions in my own functions/classes to make the names a little better? I suppose it could also add or modify some functionality in some cases, although at the moment I don't have any examples (I figure I will find ways to make them OO or make them work a little differently while I am working). If you saw a PHP developer do this, would you think "Man, this is one shoddy developer?" Additionally, I don't know much (or anything) about if/how PHP is optimized, and I know that usually PHP performace doesn't matter. But would doing something like this have a noticeable impact on the performance of my application?

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  • Cast base class object to derived class

    - by Popgalop
    Lets say I have two classes, animal and dog like this. class Animal { }; class Dog : public Animal { }; And I have an animal object named animal, that is actually an instance of dog, how would I cast it back to dog? This may seem like an odd question, but I need it because I am writing a programming language interpreter, and on the stack everything is stored as a BaseObject, and all the other datatypes extend BaseObject. How would I cast the base object from the stack, to a specific data type? I have tried something like this Dog dog = static_cast<Dog>(animal); But it gives me an error 1>------ Build started: Project: StackTests, Configuration: Debug Win32 ------ 1> StackTests.cpp 1>c:\users\owner\documents\visual studio 2012\projects\stacktests\stacktests\stacktests.cpp(173): error C2440: 'static_cast' : cannot convert from 'Animal' to 'Dog' 1> No constructor could take the source type, or constructor overload resolution was ambiguous 1>c:\users\owner\documents\visual studio 2012\projects\stacktests\stacktests\stacktests.cpp(173): error C2512: 'Dog' : no appropriate default constructor available ========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

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  • java array pass by reference does not work?

    - by stdnoit
    guys i thought almost all language including java pass array into function as reference (modifiable) but somehow it does not work here. and the testArray is still 1,2,3 with size of 3 strange enough, when if i change result[i] = 2 to a[1] =2; it work . it did pass by reference what is wrong with this code? at the end, i had a = result; (which update the a). did result get removed from stack. that is why a still get to the original a ? i am confused. thanks class Test { public static void main(String[] args) { int[] testArray = {1,2,3}; equalize(testArray, 6); System.out.println("test Array size :" + testArray.length); for(int i = 0; i < testArray.length; i++) System.out.println(testArray[i]); } public static void equalize(int[] a, int biggerSize) { if(a.length > biggerSize) throw new Error("Array size bigger than biggerSize"); int[] result = new int[biggerSize]; // System.arraycopy(a, 0, result, 0, a.length); // int array default value should be 0 for(int i = 0; i < biggerSize; i++) result[i] = 2; a = result; } }

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  • Generating a python file

    - by fema
    Hi! I'm havin issues with python (imo python itself is an issue). I have a txt file, it contains a custom language and I have to translate it to a working python code. The input: import sys n = int(sys.argv[1]) ;;print "Beginning of the program!" LOOP i in range(1,n) {print "The number:";;print i} BRANCH n < 5 {print n ;;print "less than 5"} The wanted output looks exactly like this: import sys n = int(sys.argv[1]) print "Beginning of the program!" for i in range(1,n) : print "The number:" print i if n < 5 : print n print "less than 5" The name of the input file is read from parameter. The out file is out.py. In case of a wrong parameter, it gives an error message. The ;; means a new line. When I tried to do it, I made an array, I read all the lines into it, split by " ". Then I wanted to strip it from the marks I don't need. I made 2 loops, one for the lines, one for the words. So then I started to replace the things. Everything went fine until it came to the } mark. It finds it, but it can not replace or strip it. I have no more idea what to do. Could someone help me, please? Thanks in advance!

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  • Is there any need for me to use wstring in the following case

    - by Yan Cheng CHEOK
    Currently, I am developing an app for a China customer. China customer are mostly switch to GB2312 language in their OS encoding. I need to write a text file, which will be encoded using GB2312. I use std::ofstream file I compile my application under MBCS mode, not unicode. I use the following code, to convert CString to std::string, and write it to file using ofstream std::string Utils::ToString(CString& cString) { /* Will not work correctly, if we are compiled under unicode mode. */ return (LPCTSTR)cString; } To my surprise. It just works. I thought I need to at least make use of wstring. I try to do some investigation. Here is the MBCS.txt generated. I try to print a single character named ? (its value is 0xBDC5) When I use CString to carry this character, its length is 2. When I use Utils::ToString to perform conversion to std::string, the returned string length is 2. I write to file using std::ofstream My question is : When I exam MBCS.txt using a hex editor, the value is displayed as BD (LSB) and C5 (MSB). But I am using little endian machine. Isn't hex editor should show me C5 (LSB) and BD (MSB)? I check from wikipedia. GB2312 seems doesn't specific endianness. It seems that using std::string + CString just work fine for my case. May I know in what case, the above methodology will not work? and when I should start to use wstring?

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  • Using Visual Studio 2010 Express to create a surface I can draw to

    - by Joel
    I'm coming from a Java background and trying to port a simple version of Conway's Game of Life that I wrote to C# in order to learn the language. In Java, I drew my output by inheriting from JComponent and overriding paint(). My new canvas class then had an instance of the simulation's backend which it could read/manipulate. I was then able to get the WYSIWYG GUI editor (Matisse, from NetBeans) to allow me to visually place the canvas. In C#, I've gathered that I need to override OnPaint() to draw things, which (as far as I know) requires me to inherit from something (I chose Panel). I can't figure out how to get the Windows forms editor to let me place my custom class. I'm also uncertain about where in the generated code I need to place my class. How can I do this, and is putting all my drawing code into a subclass really how I should be going about this? The lack of easy answers on Google suggests I'm missing something important here. If anyone wants to suggest a method for doing this in WPF as well, I'm curious to hear it. Thanks

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  • PHP loop hanging/interspersed/threaded through HTML

    - by sandyv
    I can't figure out how to say what I'm talking about which is a big part of why I'm stuck. In PHP I often see code like this html <?php language construct that uses brackets { some code; ?> more html <?php some more code; } ?> rest of html Is there any name for this? Having seen this lead me to try it out so here is a concrete example whose behavior doesn't make sense to me <div id="content"> <ul id="nav"> <?php $path = 'content'; $dir = dir($path); while(false !== ($file = $dir->read())) { if(preg_match('/.+\.txt/i', $file)) { echo "<li>$file</li>"; ?> </ul> <?php echo file_get_contents($path . '/' . $file); } } ?> </div> Which outputs roughly <div><ul><li></li></ul><li></li>...</div> instead of <div><ul><li></li>...</ul></div> which is what I thought would happen and what I want to happen.

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