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  • Ruby: counters, counting and incrementing

    - by Shyam
    Hi, If you have seen my previous questions, you'd already know I am a big nuby when it comes to Ruby. So, I discovered this website which is intended for C programming, but I thought whatever one can do in C, must be possible in Ruby (and more readable too). The challenge is to print out a bunch of numbers. I discovered this nifty method .upto() and I used a block (and actually understanding its purpose). However, in IRb, I got some unexpected behavior. class MyCounter def run 1.upto(10) { |x| print x.to_s + " " } end end irb(main):033:0> q = MyCounter.new => #<MyCounter:0x5dca0> irb(main):034:0> q.run 1 2 3 4 5 6 7 8 9 10 => 1 I have no idea where the = 1 comes from :S Should I do this otherwise? I am expecting to have this result: 1 2 3 4 5 6 7 8 9 10 Thank you for your answers, comments and feedback!

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  • Creating a web application that can be extended by plugins/modules

    - by Adam Pope
    I'm currently involved with developing a C# CMS-like web application which will be used to standardise our development of websites. From the outset, the idea has been to keep the core as simple as possible to avoid the complexity and menu/option overload that blights many CMS systems. This simple core is now complete and working very well. We envisisaged that the system would be able to accept plugins or modules which would extend the core functionality to suit a given projects needs. These would also be re-usable across projects. For example, a basic catalogue and shopping basket might be needed. All the code for such extensions should be in seperate assemblies. They should be able to provide their own admin interfaces and front-end code from this library. The system should search for available plugins and give the admin user the option to enable/disable the feature. (This is all very much like WordPress plugins) It is crucial that we attack this problem in the correct way, so I'm trying to perform as much due dilligence as possible before jumping in. I am aware of the Plugin Pattern (http://msdn.microsoft.com/en-us/library/ms972962.aspx) and have read some articles on it's use. It seems reasonable but I'm not convinced it's necessarily the correct/best technique for this situation. It seems more suited to processing applications (image/audio manipulation, maths etc). Are there any other options for achieving this kind of UI extensibility functionality? Or is the plugin pattern the way to go? I'd also be interested if anybody has links to articles that explain using the plugin pattern for this purpose?

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  • In Perl, how can I wait for threads to end in parallel?

    - by Pmarcoen
    I have a Perl script that launches 2 threads,one for each processor. I need it to wait for a thread to end, if one thread ends a new one is spawned. It seems that the join method blocks the rest of the program, therefore the second thread can't end until everything the first thread does is done which sort of defeats its purpose. I tried the is_joinable method but that doesn't seem to do it either. Here is some of my code : use threads; use threads::shared; @file_list = @ARGV; #Our file list $nofiles = $#file_list + 1; #Real number of files $currfile = 1; #Current number of file to process my %MSG : shared; #shared hash $thr0 = threads->new(\&process, shift(@file_list)); $currfile++; $thr1 = threads->new(\&process, shift(@file_list)); $currfile++; while(1){ if ($thr0->is_joinable()) { $thr0->join; #check if there are files left to process if($currfile <= $nofiles){ $thr0 = threads->new(\&process, shift(@file_list)); $currfile++; } } if ($thr1->is_joinable()) { $thr1->join; #check if there are files left to process if($currfile <= $nofiles){ $thr1 = threads->new(\&process, shift(@file_list)); $currfile++; } } } sub process{ print "Opening $currfile of $nofiles\n"; #do some stuff if(some condition){ lock(%MSG); #write stuff to hash } print "Closing $currfile of $nofiles\n"; } The output of this is : Opening 1 of 4 Opening 2 of 4 Closing 1 of 4 Opening 3 of 4 Closing 3 of 4 Opening 4 of 4 Closing 2 of 4 Closing 4 of 4

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  • Using an element against an entire list in Haskell

    - by Snick
    I have an assignment and am currently caught in one section of what I'm trying to do. Without going in to specific detail here is the basic layout: I'm given a data element, f, that holds four different types inside (each with their own purpose): data F = F Float Int, Int a function: func :: F -> F-> Q Which takes two data elements and (by simple calculations) returns a type that is now an updated version of one of the types in the first f. I now have an entire list of these elements and need to run the given function using one data element and return the type's value (not the data element). My first analysis was to use a foldl function: myfunc :: F -> [F] -> Q myfunc y [] = func y y -- func deals with the same data element calls myfunc y (x:xs) = foldl func y (x:xs) however I keep getting the same error: "Couldn't match expected type 'F' against inferred type 'Q'. In the first argument of 'foldl', namely 'myfunc' In the expression: foldl func y (x:xs) I apologise for such an abstract analysis on my problem but could anyone give me an idea as to what I should do? Should I even use a fold function or is there recursion I'm not thinking about?

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  • Decimal To Octal Converter, last digit issue

    - by Srishan Supertramp
    I tried making a C program to convert a user entered decimal number to octal. I wrote the C code with my own logic without any research of how other users try to do it. It works fine for the number 601 and some other numbers but for most numbers it returns the octal equivalent with the last digit being 1 less than it should be. For 75 it returns 112 instead of 113. I realize using printf with %o gets the job done but it's kind of defeating the purpose of learning to program. Here's my code: #include <stdio.h> #include <math.h> /* converting decimal to octal */ int main() { int n,x,y,p,s; printf("Enter a decimal number "); scanf("%d",&x); s=0;p=0; while (x!=0) { y=x%8; s=s+y*pow(10,p); x=(x-y)/8; p=p+1; } printf("the octal equivalent is: %d\n",s); getch(); return 0; }

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  • Android Service setForeground While Display Sleeps

    - by c12
    I have a background Android Service that's purpose is to communicate with another device (non-phone) using a Bluetooth socket. Everything works fine except that the service gets stopped and restarted by the OS when the phone display is sleeping. This restart sometimes leaves a 15-20 minute gaps where there is no communication between the Service and the Bluetooth device and I need to be able to query the device every minute. Is startForeground the proper approach? Attempted to use: startForeground(int, Notification) //still see gaps when phone sleeps Service: public class ForegroundBluetoothService extends Service{ private boolean isStarted = false; @Override public void onDestroy() { super.onDestroy(); stop(); } /** * @see android.app.Service#onBind(android.content.Intent) */ @Override public IBinder onBind(Intent intent) { return null; } /** * @see android.app.Service#onStartCommand(android.content.Intent, int, int) */ @Override public int onStartCommand(Intent intent, int flags, int startId) { loadServiceInForeground(); return(START_STICKY); } private void loadServiceInForeground() { if (!isStarted) { isStarted=true; Notification notification = new Notification(R.drawable.icon, "Service is Running...", System.currentTimeMillis()); Intent notificationIntent = new Intent(this, MainScreen.class); PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, notificationIntent, 0); notification.setLatestEventInfo(this, "Notification Title", "Service is Running...", pendingIntent); startForeground(12345, notification); try{ queryTheBluetoothDevice(); } catch(Exception ex){ ex.printStackTrace(); } } } private void stop() { if (isStarted) { isStarted=false; stopForeground(true); } } }

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  • A beginner question on passthru() function in PHP

    - by Robert
    Hi all, I've used the following code to do an XSLT translation in PHP and save the result SVG file into a sub folder: $command = $java . $saxon . $target2 . ' ' . $xsl2.' '.$param; ob_start(); passthru($command, $result); $content_grabbed=ob_get_contents(); ob_end_clean(); $info = pathinfo($_FILES['file']['name']); $file_name= basename($_FILES['file']['name'],'.'.$info['extension']); $myFile = "images/convert/".$file_name."_".$_POST["mydropdown"].".svg"; $fh = fopen($myFile, 'w') or die("can't open file"); fwrite($fh, $content_grabbed); fclose($fh); It does a very simple SVG to SVG transformation, and created the resulting SVG file. the $command is just a simple java -jar saxon.jar input.xml stylesheet java command. The current situation is ,the file gets created perfectly, however, the error gets shown in browser, probably because I inserted the "ob_start" before passthru() command. I am thinking of making use of an argument that comes with the saxon.jar, that is "-o output_file_name". Because the final purpose is not to display the resulting SVG to the browser, but instead creating an SVG file ,and provide the link to the user for downloading. Are there any better ways to handle this problem, I am still thinking about how to get rid of the result that gets shown in the browser that is sent by the "passthru()". Thanks in advance for suggestions!

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  • Redirect requests only if the file is not found?

    - by ZenBlender
    I'm hoping there is a way to do this with mod_rewrite and Apache, but maybe there is another way to consider too. On my site, I have directories set up for re-skinned versions of the site for clients. If the web root is /home/blah/www, a client directory would be /home/blah/www/clients/abc. When you access the client directory via a web browser, I want it to use any requested files in the client directory if they exist. Otherwise, I want it to use the file in the web root. For example, let's say the client does not need their own index.html. Therefore, some code would determine that there is no index.html in /home/blah/www/clients/abc and will instead use the one in /home/blah/www. Keep in mind that I don't want to redirect the client to the web root at any time, I just want to use the web root's file with that name if the client directory has not specified its own copy. The web browser should still point to /clients/abc whether the file exists there or in the root. Likewise, if there is a request for news.html in the client directory and it DOES exist there, then just serve that file instead of the web root's news.html. The user's experience should be seamless. I need this to work for requests on any filename. If I need to, for example, add a new line to .htaccess for every file I might want to redirect, it rather defeats the purpose as there is too much maintenance needed, and a good chance for errors given the large number of files. In your examples, please indicate whether your code goes in the .htaccess file in the client directory, or the web root. Web root is preferred. Thanks for any suggestions! :)

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  • Optimizing this "Boundarize" method for Numerics in Ruby

    - by mstksg
    I'm extending Numerics with a method I call "Boundarize" for lack of better name; I'm sure there are actually real names for this. But its basic purpose is to reset a given point to be within a boundary. That is, "wrapping" a point around the boundary; if the area is betweeon 0 and 100, if the point goes to -1, -1.boundarize(0,100) = 99 (going one too far to the negative "wraps" the point around to one from the max). 102.boundarize(0,100) = 2 It's a very simple function to implement; when the number is below the minimum, simply add (max-min) until it's in the boundary. If the number is above the maximum, simply subtract (max-min) until it's in the boundary. One thing I also need to account for is that, there are cases where I don't want to include the minimum in the range, and cases where I don't want to include the maximum in the range. This is specified as an argument. However, I fear that my current implementation is horribly, terribly, grossly inefficient. And because every time something moves on the screen, it has to re-run this, this is one of the bottlenecks of my application. Anyone have any ideas? module Boundarizer def boundarize min=0,max=1,allow_min=true,allow_max=false raise "Improper boundaries #{min}/#{max}" if min >= max new_num = self if allow_min while new_num < min new_num += (max-min) end else while new_num <= min new_num += (max-min) end end if allow_max while new_num > max new_num -= (max-min) end else while new_num >= max new_num -= (max-min) end end return new_num end end class Numeric include Boundarizer end

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  • GUID or int entity key with SQL Compact/EF4?

    - by David Veeneman
    This is a follow-up to an earlier question I posted on EF4 entity keys with SQL Compact. SQL Compact doesn't allow server-generated identity keys, so I am left with creating my own keys as objects are added to the ObjectContext. My first choice would be an integer key, and the previous answer linked to a blog post that shows an extension method that uses the Max operator with a selector expression to find the next available key: public static TResult NextId<TSource, TResult>(this ObjectSet<TSource> table, Expression<Func<TSource, TResult>> selector) where TSource : class { TResult lastId = table.Any() ? table.Max(selector) : default(TResult); if (lastId is int) { lastId = (TResult)(object)(((int)(object)lastId) + 1); } return lastId; } Here's my take on the extension method: It will work fine if the ObjectContext that I am working with has an unfiltered entity set. In that case, the ObjectContext will contain all rows from the data table, and I will get an accurate result. But if the entity set is the result of a query filter, the method will return the last entity key in the filtered entity set, which will not necessarily be the last key in the data table. So I think the extension method won't really work. At this point, the obvious solution seems to be to simply use a GUID as the entity key. That way, I only need to call Guid.NewGuid() method to set the ID property before I add a new entity to my ObjectContext. Here is my question: Is there a simple way of getting the last primary key in the data store from EF4 (without having to create a second ObjectContext for that purpose)? Any other reason not to take the easy way out and simply use a GUID? Thanks for your help.

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  • Where should global Application Settings be stored on Windows 7?

    - by Kerido
    Hi everybody, I'm working hard on making my product work seamlessly on Windows 7. The problem is that there is a small set of global (not user-specific) application settings that all users should be able to change. On previous versions I used HKLM\Software\__Company__\__Product__ for that purpose. This allowed Power Users and Administrators to modify the Registry Key and everything worked correctly. Now that Windows Vista and Windows 7 have this UAC feature, by default, even an Administrator cannot access the Key for writing without elevation. A stupid solution would, of course, mean adding requireAdministrator option into the application manifest. But this is really unprofessional since the product itself is extremely far from administration-related tasks. So I need to stay with asInvoker. Another solution could mean programmatic elevation during moments when write access to the Registry Key is required. Let alone the fact that I don't know how to implement that, it's pretty awkward also. It interferes with normal user experience so much that I would hardly consider it an option. What I know should be relatively easy to accomplish is adding write access to the specified Registry Key during installation. I created a separate question for that. This also very similar to accessing a shared file for storing the settings. My feeling is that there must be a way to accomplish what I need, in a way that is secure, straightforward and compatible with all OS'es. Any ideas?

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  • How to keep windows from paging block of memory

    - by photo_tom
    We are working on a Vista/Windows 7 applicaiton that will be running in 64 bit mode using VS2008/C++. We will be needing to cache hundreds of 2-3 mb blobs of data in RAM for performance reasons up to some memory limit. Our usage profile is such that we cannot read the data in fast enough if it is all on the the disk. Cached Memory usage will be larger than 1gb memory used. For this to work well, we need to ensure that Windows does not page this memory out as it will defeat the purpose of why we are doing this. I've done a fair amount of research and cannot find documenation that states exactly how to do this. I've seen several references that infer memory mapped files work this way. Is there an expert who can clarify this for me? I'm aware there are other programs that we could adapt to do this, for example, splitting the blobs and loading into memcache or inmemory databases, but they all have too many problems with performance or code complexity. Suggestions?

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  • Can one connection get details of another? Or, how can I get the most detailed pending transaction

    - by bob-the-destroyer
    Is there a Mysql statement which provides full details of any other open connection or user? For this particular case, on myisam tables specifically. Looking at Mysql's SHOW TABLE STATUS documentation, it's missing some very important information for my purpose. For example: remote odbc connection one is inserting several thousand records, which due to a slow connection speed can take up to an hour. Tcp connection two, using PHP on the server's localhost, is running select queries with aggregate functions on that data. Before allowing connection two to run those queries, I'd like connection two to first check to make sure there's no pending inserts on any other connection on those specific tables so it can instead wait until all data is available. If the table is currently being written to, I'd like to spit back to the user of connection two an approximation of how much longer to wait based on the number of pending inserts. Ideally by table, I'd like to get back using a query the timestamp when connection one began the write, total inserts left to be done, and total inserts already completed. Instead of insert counts, even knowing number of bytes written and left to write would work just fine here. Obviously since connection two is a tcp connection via a PHP script, all I can really use in that script is some sort of query. I suppose if I have to, since it is on localhost, I can exec() it if the only way is by a mysql command line option that outputs this info, but I'd rather not. I suppose I could simply update a custom-made transaction log before and after this massive insert task which the PHP script can check, but hopefully there's already a built-in Mysql feature I can take advantage of.

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  • database design - empty fields

    - by imanc
    Hey, I am currently debating an issue with a guy on my dev team. He believes that empty fields are bad news. For instance, if we have a customer details table that stores data for customers from different countries, and each country has a slightly different address configuration - plus 1-2 extra fields, e.g. French customer details may also store details for entry code, and floor/level plus title fields (madamme, etc.). South Africa would have a security number. And so on. Given that we're talking about minor variances my idea is to put all of the fields into the table and use what is needed on each form. My colleague believes we should have a separate table with extra data. E.g. customer_info_fr. But this seams to totally defeat the purpose of a combined table in the first place. His argument is that empty fields / columns is bad - but I'm struggling to find justification in terms of database design principles for or against this argument and preferred solutions. Another option is a separate mini EAV table that stores extra data with parent_id, key, val fields. Or to serialise extra data into an extra_data column in the main customer_data table. I think I am confused because what I'm discussing is not covered by 3NF which is what I would typically use as a reference for how to structure data. So my question specifically: - if you have slight variances in data for each record (1-2 different fields for instance) what is the best way to proceed?

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  • Running Cargo From Maven antrun Plugin

    - by Frank
    I have a maven (multi-module) project creating some WAR and EAR files for JBoss AS 7.1.x. For one purpose, I need to deploy one generated EAR file of one module to a fresh JBoss instance and run it, call some REST web service calls against it and stop JBoss. Then I need to package the results of these calls that were written to the database. Currently, I am trying to use CARGO and the maven ant run plugin to perform this task. Unfortunately, I cannot get the three (maven, ant run and CARGO) to play together. I don't have the uberjar that is used in the ant examples of cargo. How can I configure the ant run task so that the cargo ant task can create, start, deploy my JBoss? Ideally the one unpacked and configured by the cargo-maven2-plugin in another phase? Or, is there a better way to achieve my goal of creating the database? I cannot really use the integration-test phase, as it is executed after the package phase. So, I plan to do it all in compile phase using antrun.

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  • Can you recommend an easy to use easy to develop CMS?

    - by el_at_yahoo
    We need some easy way to manage web sites at our company, and we are evaluating some CMS tools for this purpose. We do not yet know what features the sites will need to have (but it will definitely be something with lots of functionalities), so we are looking for something with lots of features and more importantly to be easily extensible (if it does not have some feature, we at least want to be able to build-it by ourselves). We have no experience with Content Management Systems but we do with Java, so it has to be something written in Java. We evaluated some tools and from our perspective the following seem the promising of them (in no particular order): OpenCMS dotCMS (Community Edition vs Enterprise Edition) InfoGlue Alfresco (EE vs CE) Magnolia (EE vs EE Pro vs CE) Jahia (CE vs EE) Since we have no experience with either one of them, we were wondering if someone of you who have can share some information about how good they are or how easily they can be used and extended. I know similar questions have been asked on SO and I also know this is highly subjective and people will vote for closing it as soon as it is posted, but for us it is important to know what difficulties other people have been facing in using the above tools (we don’t want to walk a path that takes nowhere if other people already know it leads nowhere). Others could then vote on the posted answers if they agree or not. From your experience, which from the above mentioned CMSs is the more easily extensible, the easier to use, the easiest to learn etc? Thank you and Happy Holidays to all.

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  • Designing a chain of states

    - by devoured elysium
    I want to model a kind of FSM(Finite State Machine). I have a sequence of states (let's say, from StateA to StateZ). This sequence is called a Chain and is implemented internally as a List. I will add states by the order I want them to run. My purpose is to be able to make a sequence of actions in my computer (for example, mouse clicks). (I know this has been done a zillion times). So a state is defined as a: boolean Precondition() <- Checks to see if for this state, some condition is true. For example, if I want to click in the Record button of a program, in this method I would check if the program's process is running or not. If it is, go to the next state in the chain list, otherwise, go to what was defined as the fail state (generally is the first state of them all). IState GetNextState() <- Returns the next state to evaluate. If Precondition() was sucessful, it should yield the next state in the chain otherwise it should yield the fail state. Run() Simply checks the Precondition() and sets the internal data so GetNextState() works as expected. So, a naive approach to this would be something like this: Chain chain = new Chain(); //chain.AddState(new State(Precondition, FailState, NextState) <- Method structure chain.AddState(new State(new WinampIsOpenCondition(), null, new <problem here, I want to referr to a state that still wasn't defined!>); The big problem is that I want to make a reference to a State that at this point still wasn't defined. I could circumvent the problem by using strings when refrering to states and using an internal hashtable, but isn't there a clearer alternative? I could just pass only the pre-condition and failure states in the constructor, having the chain just before execution put in each state the correct next state in a public property but that seems kind of awkward.

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  • Can I create an application using SlimDX relying on the DirectX DLLs already bundled with Vista/Win7

    - by norheim.se
    I'm working on a .NET application that requires the use of accelerated graphics, currently DirectX 9.0c. The software is quite graphics intensive and must, in addition, be launchable from a CD or by ClickOnce without the user requiring administrator's permissions. I currently use SlimDX, which works great featurewise, but the users are getting rather annoyed by having to install the DirectX redistributable. Especially since this does require elevated permissions. It is rather hard to explain to them why the version of DirectX already bundled with their OS is not sufficient. After all - DirectX 9.0c has been around since 2004, and I'm not using any new fancy features. The ability to deliver an application that "just works" in Vista or Windows 7, without any particular additional prerequisites would be a huge advantage. Therefore: Is there any way I can build an application using DirectX 9.0c based on SlimDX, that relies only on the libraries provided in the standard Windows Vista/Win7 installation? That is - without requiring the additional DirectX redistributable to be installed? If not - is there any other managed (and preferably not abandoned) DirectX wrapper that can serve this purpose? Thanks in advance!

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  • JQuery modal box form validation

    - by vikitor
    Hi, I was using a view to create an object for my specific project, but now I have to adapt this to another requirements, such as the creation of this object must be integrated in the creation of another one. The thing is, that this object must be created before starting to create the other one, and the way of doing it will be poping up a modal dialog box with JQuery with the form to create it. I've got to adapt the creation and it works fine, except for the validation messages. It is made in the controller like : if (not.NotName.Trim().Length == 0) { ModelState.AddModelError("NotName", "Name is required"); } if (_notification.checkIfExists(not.NotName, not.NotRecID)) { ModelState.AddModelError("NotName", "Notification already exists"); } And before with a normal view it worked fine, but now I'm not able to get the validation messages as I did. How can you get this validation messages thrown by the controller in the Modal Box? Because now when I made a mistake on purpose in the form in order to get the error it doesn't appear. I've seen the error is displayed in the site, because I've seen it on firebug, but it doesn't appear in my model box. How can I retrieve this errors? Do you know any tutorial that could help me with this? Thank you

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  • PyGTK: Manually render an existing widget at a given Rectangle? (TextView in a custom CellRenderer)

    - by NicDumZ
    Hello! I am trying to draw a TextView into the cell of a TreeView. (Why? I would like to have custom tags on text, so they can be clickable and trigger different actions/popup menus depending on where user clicks). I have been trying to write a customized CellRenderer for this purpose, but so far I failed because I find it extremely difficult to find generic documentation on rendering design in gtk. More than an answer at the specific question (that might be hard/not doable, and I'm not expecting you to do everything for me), I am first looking for documentation on how a widget is rendered, to understand how one is supposed to implement a CellRenderer. Can you share any link that explains, either for gtk or for pygtk, the rendering mechanism? More specifically: size allocation mechanism (should I say protocol?). I understand that a window has a defined size, and then queries its children, saying "my size is w x h, what would be your ideal size, buddy?", and then sometimes shrinks children when all children cant fit together at their ideal sizes. Any specific documentation on that, and on particular on when this happens during rendering? How are rendered "builtin" widgets? What kind of methods do they call on Widget base class? On the parent Window? When? Do they use pango.Layout? can you manually draw a TextView onto a pango.Layout object? This link gives an interesting example showing how you can draw content in a pango.Layout object and use it in a CellRenderer. I guess that I could adapt it if only I understood how TextView widget are rendered. Or perhaps, to put it more simply: given an existing widget instance, how does one render it at a specific gdk.Rectangle? Thanks a lot.

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  • `enable_shared_from_this` has a non-virtual destructor

    - by Shtééf
    I have a pet project with which I experiment with new features of the upcoming C++0x standard. While I have experience with C, I'm fairly new to C++. To train myself into best practices, (besides reading a lot), I have enabled some strict compiler parameters (using GCC 4.4.1): -std=c++0x -Werror -Wall -Winline -Weffc++ -pedantic-errors This has worked fine for me. Until now, I have been able to resolve all obstacles. However, I have a need for enable_shared_from_this, and this is causing me problems. I get the following warning (error, in my case) when compiling my code (probably triggered by -Weffc++): base class ‘class std::enable_shared_from_this<Package>’ has a non-virtual destructor So basically, I'm a bit bugged by this implementation of enable_shared_from_this, because: A destructor of a class that is intended for subclassing should always be virtual, IMHO. The destructor is empty, why have it at all? I can't imagine anyone would want to delete their instance by reference to enable_shared_from_this. But I'm looking for ways to deal with this, so my question is really, is there a proper way to deal with this? And: am I correct in thinking that this destructor is bogus, or is there a real purpose to it?

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  • Performance Comparison of Shell Scripts vs high level interpreted langs (C#/Java/etc.)

    - by dferraro
    Hi all, First - This is not meant to be a 'which is better, ignorant nonionic war thread'... But rather, I generally need help in making an architecture decision / argument to put forward to my boss. Skipping the details - I simply just would love to know and find the results of anyone who has done some performance comparisons of Shell vs [Insert General Purpose Programming Language (interpreted) here), such as C# or Java... Surprisingly, I have spent some time on Google on searching here to not find any of this data. Has anyone ever done these comparisons, in different use-cases; hitting a database like in a XYX # of loops doing different types of SQL (Oracle pref, but MSSQL would do) queries such as any of the CRUD ops - and also not hitting database and just regular 50k loop type comparison doing different types of calculations, and things of that nature? In particular - for right now, I need to a comparison of hitting an Oracle DB from a shell script vs, lets say C# (again, any GPPL thats interpreted would be fine, even the higher level ones like Python). But I also need to know about standard programming calculations / instructions/etc... Before you ask 'why not just write a quick test yourself? The answer is: I've been a Windows developer my whole life/career and have very limited knowledge of Shell scripting - not to mention *nix as a whole.... So asking the question on here from the more experienced guys would be grealty beneficial, not to mention time saving as we are in near perputual deadline crunch as it is ;). Thanks so much in advance,

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  • UITableViewRowAnimationBottom doesn't work for last row

    - by GendoIkari
    I've come across a very similar question here: Inserting row to end of table with UITableViewRowAnimationBottom doesn't animate., though no answers have been given. His code was also a little different than mine. I have an extremely simple example, built from the Navigation application template. NSMutableArray *items; - (void)viewDidLoad { [super viewDidLoad]; items = [[NSMutableArray array] retain]; self.navigationItem.rightBarButtonItem = [[[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemAdd target:self action:@selector(addItem)] autorelease]; } - (void)addItem{ [items insertObject:@"new" atIndex:0]; [self.tableView insertRowsAtIndexPaths:[NSArray arrayWithObject:[NSIndexPath indexPathForRow:0 inSection:0]] withRowAnimation:UITableViewRowAnimationBottom]; } - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section { return items.count; } - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { static NSString *CellIdentifier = @"Cell"; UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier]; if (cell == nil) { cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease]; } cell.textLabel.text = [items objectAtIndex:indexPath.row]; return cell; } - (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath { if (editingStyle == UITableViewCellEditingStyleDelete) { [items removeObjectAtIndex:indexPath.row]; [tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationBottom]; } } The problem is, when I either insert or delete the very last row in the table, the animation doesn't work at all; the row just appears or disappears instantly. This only happens with UITableViewRowAnimationBottom, but that's the animation that makes the most sense for creating or deleting table cells in this way. Is this a bug in Apple's framework? Or does it do this on purpose? Would it make sense to add an extra cell to the count, and then setup this cell so that it looks like it's not there at all, just to get around this behavior?

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  • Is locking on the requested object a bad idea?

    - by Quick Joe Smith
    Most advice on thread safety involves some variation of the following pattern: public class Thing { private static readonly object padlock = new object(); private string stuff, andNonsense; public string Stuff { get { lock (Thing.padlock) { if (this.stuff == null) this.stuff = "Threadsafe!"; } return this.stuff; } } public string AndNonsense { get { lock (Thing.padlock) { if (this.andNonsense == null) this.andNonsense = "Also threadsafe!"; } return this.andNonsense; } } // Rest of class... } In cases where the get operations are expensive and unrelated, a single locking object is unsuitable because a call to Stuff would block all calls to AndNonsense, degrading performance. And rather than create a lock object for each call, wouldn't it be better to acquire the lock on the member itself (assuming it is not something that implements SyncRoot or somesuch for that purpose? For example: public string Stuff { get { lock (this.stuff) { // Pretend that this is a very expensive operation. if (this.stuff == null) this.stuff = "Still threadsafe and good?"; } return this.stuff; } } Strangely, I have never seen this approach recommended or warned against. Am I missing something obvious?

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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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