Search Results

Search found 5044 results on 202 pages for 'clausal logic'.

Page 182/202 | < Previous Page | 178 179 180 181 182 183 184 185 186 187 188 189  | Next Page >

• ANSI C as core of a C# project? Is this possible?

  - by Nektarios

  I'm writing a NON-GUI app which I want to be cross platform between OS X and Windows. I'm looking at the following architecture, but I don't know if it will work on the windows side: (Platform specific entry point) - ANSI C main loop = ANSI C model code doing data processing / logic = (Platform specific helpers) So the core stuff I'm planning to write in regular ANSI C, because A) it should be platform independent, B) I'm extremely comfortable with C, C) It can do the job and do it well (Platform specific entry point) can be written in whatever necessary to get the job done, this is a small amount of code, doesn't matter to me. (Platform specific helpers) is the sticky thing. This is stuff like parsing XML, accessing databases, graphics toolkit stuff, whatever. Things that aren't easy in C. Things that modern languages/frameworks will give for free. On OS X this code will be written in Objective-C interfacing with Cocoa. On Windows I'm thinking my best bet is to use C# So on Windows my architecture (simplified) looks like (C# or C?) - ANSI C - C# Is this possible? Some thoughts/suggestions so far.. 1) Compile my C core as a .dll -- this is fine, but seems there's no way to call my C# helpers unless I can somehow get function pointers and pass them to my core, but that seems unlikely 2) Compile a C .exe and a C# .exe and have them talk via shared memory or some kind of IPC. I'm not entirely opposed to this but it obviously introduces a lot of complexity so it doesn't seem ideal 3) Instead of C# use C++, it gets me some nice data management stuff and nice helper code. And I can mix it pretty easily. And the work I do could probably easily port to Linux. But I really don't like C++, and I don't want this to turn in to a 3rd-party-library-fest. Not that it's a huge deal, but it's 2010.. anything for basic data management should be built in. And targetting Linux is really not a priority. Note that no "total" alternatives are OK as suggested in other similar questions on SO I've seen; java, RealBasic, mono.. this is an extremely performance intensive application doing soft realtime for game/simulation purposes, I need C & friends here to do it right (maybe you don't, but I do)

  Read the article

• Separation of domain and ui layer in a composite

  - by hansmaad

  Hi all, i'm wondering if there is a pattern how to separate the domain logic of a class from the ui responsibilities of the objects in the domain layer. Example: // Domain classes interface MachinePart { CalculateX(in, out) // Where do we put these: // Draw(Screen) ?? // ShowProperties(View) ?? // ... } class Assembly : MachinePart { CalculateX(in, out) subParts } class Pipe : MachinePart { CalculateX(in, out) length, diamater... } There is an application that calculates the value X for machines assembled from many machine parts. The assembly is loaded from a file representation and is designed as a composite. Each concrete part class stores some data to implement the CalculateX(in,out) method to simulate behaviour of the whole assembly. The application runs well but without GUI. To increase the usability a GUi should be developed on top of the existing implementation (changes to the existing code are allowed). The GUI should show a schematic graphical representation of the assembly and provide part specific dialogs to edit several parameters. To achieve these goals the application needs new functionality for each machine part to draw a schematic representation on the screen, show a property dialog and other things not related to the domain of machine simulation. I can think of some different solutions to implement a Draw(Screen) functionality for each part but i am not happy with each of them. First i could add a Draw(Screen) method to the MachinePart interface but this would mix-up domain code with ui code and i had to add a lot of functionality to each machine part class what makes my domain model hard to read and hard to understand. Another "simple" solution is to make all parts visitable and implement ui code in visitors but Visitor does not belong to my favorite patterns. I could derive UI variants from each machine part class to add the UI implementation there but i had to check if each part class is suited for inheritance and had to be careful on changes to the base classes. My currently favorite design is to create a parallel composite hierarchy where each component stores data to define a machine part, has implementation for UI methods and a factory method which creates instances of the corresponding domain classes, so that i can "convert" a UI assembly to a domain assembly. But there are problems to go back from the created domain hierarchy to the UI hierarchy for showing calculation results in the drawing for example (imagine some parts store some values during the calculation i want to show in the schematic representation after the simluation). Maybe there are some proven patterns for such problems?

  Read the article

• Visual studio 2010 colourizers, intellisense and the rest. Where to start!!

  - by Owen

  Ok, before I begin I realize that there is a lot of documentation on this subject but I have thus far failed to get even basic colourization working for VS2010. My goal is to simply get to a point where I can open a document and everything is coloured red, from here I can implement the relevant parsing logic. Here's what I have tried/found: 1) Downloaded all the relevent SDK's and such- Found the ook sample (http://code.msdn.microsoft.com/ookLanguage) - didn't build, didn't work. 2) Knowing almost nothing about MEF read through "Implementing a Language Service By Using the Managed Package Framework" - http://msdn.microsoft.com/en-us/library/bb166533(v=VS.100).aspx This was pretty much a copy and paste of all the basic stuff here, and also updating some references which were out of date with the sample see: http://social.msdn.microsoft.com/Forums/en-US/vsx/thread/a310fe67-afd2-4592-b295-3fc86fec7996 Now, I have got to a point where when running the package MEF appears to have hooked up correctly (I know this because with the debugger open I can see that the packages initialize and FDoIdle methods are being hit). When I open a file of the extension I have registered with the ProvideLanguageExtensionAttribute everything dies as if in an endless loop, yet no debug symbols hit (though they are loaded). Looking at the ook sample and the MEF examples they seem to be totally different approaches to the same problem. In the ook sample there are notions of Clasifications and Completion controllers which aren't mentioned in the MEF example. Also, they don't seem to create a Package or Language service, so I have no idea how it should work? With the MEF example, my assumption is that I need to hook into the "IScanner.ScanTokenAndProvideInfoAboutIt" to provide syntax highlighting? Which would be fine if I could ever hit this method. So my first question I guess is which approach should I be taking here? Or do they both somehow tie together? My second questions is, where can I find a basic fully working project that implements bog standard basic syntax highlighting and intellisense or VS2010? Thirdly, in the MEF example when I created a Package there were a bunch of test projects created for me. I appears that the integration tests launch the VS2010 test rig somehow, but the test fails. It would be good to write my service with tests but I have no idea what/how I can test each interaction so any references to testing Language services would be helpful. Finally, please throw any resource/book links my way that I may find useful. Cheers, Chris. N.B. Sorry I realize this is part question part rant, but I have never been so confused.

  Read the article

• Unable to find assembly, C#

  - by PlasmaCube

  So, here's the deal. I've got two ASP.NET applications, both of which use SQLServer Session State management. They also both use the same server. I've got a custom session class in an external DLL, which fully implements serialization, and which both applications have referenced. Each application, in turn, has a class which inherits from the DLL class, and both applications use their own respective classes for their session state. Now, what I was trying to accomplish was that if you wanted to go to the other application, it could look in the session (they all use the same session key) and treat the existing object there as the base (the one from the DLL), extract whatever login info you need, then overwrite the session object with your own. Unfortunately, when the second application attempts to read the session, it seems that it looks for the DLL of the first application, and when it can't find it, it throws an exception. Is there a flaw in my logic? Here's an example: // Global.asax of the 1st app protected void Session_Start(object sender, EventArgs e) { Session.Add( "UserSessionKey", new FirstUserSession()); // FirstUserSession inherits from BaseUserSession } Now the second application: // Global.asax of 2nd app protected void Session_Start(object sender, EventArgs e) { if (Session["UserSessionKey"] != null) { BaseUserSession existing = (BaseUserSession)Session["UserSessionKey"]; SecondUserSession session = new SecondUserSession(); // This also inherits from BaseUserSession session.Authenticated = existing.Authenticated; session.Id = existing.Id; session.Role = existing.Role; Session.Add("UserSessionKey", session); } else { Session.Add("UserSessionKey", new SecondUserSession()); } } Here's the exception stack trace. In this case, "MyCBC" is the real name of the first app, and "ASPTesting" is the second app. [SerializationException: Unable to find assembly 'MyCBC, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null'.] System.Runtime.Serialization.Formatters.Binary.BinaryAssemblyInfo.GetAssembly() +1871092 System.Runtime.Serialization.Formatters.Binary.ObjectReader.GetType(BinaryAssemblyInfo assemblyInfo, String name) +7545734 System.Runtime.Serialization.Formatters.Binary.ObjectMap..ctor(String objectName, String[] memberNames, BinaryTypeEnum[] binaryTypeEnumA, Object[] typeInformationA, Int32[] memberAssemIds, ObjectReader objectReader, Int32 objectId, BinaryAssemblyInfo assemblyInfo, SizedArray assemIdToAssemblyTable) +120 System.Runtime.Serialization.Formatters.Binary.ObjectMap.Create(String name, String[] memberNames, BinaryTypeEnum[] binaryTypeEnumA, Object[] typeInformationA, Int32[] memberAssemIds, ObjectReader objectReader, Int32 objectId, BinaryAssemblyInfo assemblyInfo, SizedArray assemIdToAssemblyTable) +52 System.Runtime.Serialization.Formatters.Binary.__BinaryParser.ReadObjectWithMapTyped(BinaryObjectWithMapTyped record) +190 System.Runtime.Serialization.Formatters.Binary.__BinaryParser.ReadObjectWithMapTyped(BinaryHeaderEnum binaryHeaderEnum) +61 System.Runtime.Serialization.Formatters.Binary.__BinaryParser.Run() +253 System.Runtime.Serialization.Formatters.Binary.ObjectReader.Deserialize(HeaderHandler handler, __BinaryParser serParser, Boolean fCheck, Boolean isCrossAppDomain, IMethodCallMessage methodCallMessage) +168 System.Runtime.Serialization.Formatters.Binary.BinaryFormatter.Deserialize(Stream serializationStream, HeaderHandler handler, Boolean fCheck, Boolean isCrossAppDomain, IMethodCallMessage methodCallMessage) +203 System.Web.Util.AltSerialization.ReadValueFromStream(BinaryReader reader) +788 System.Web.SessionState.SessionStateItemCollection.ReadValueFromStreamWithAssert() +55 System.Web.SessionState.SessionStateItemCollection.DeserializeItem(String name, Boolean check) +281 System.Web.SessionState.SessionStateItemCollection.get_Item(String name) +19 System.Web.SessionState.HttpSessionStateContainer.get_Item(String name) +13 System.Web.SessionState.HttpSessionState.get_Item(String name) +13 ASPTesting._Default.Page_Load(Object sender, EventArgs e) in C:\Documents and Settings\sarsstu\My Documents\Projects\Testing\ASPTesting\ASPTesting\Default.aspx.cs:20 System.Web.Util.CalliHelper.EventArgFunctionCaller(IntPtr fp, Object o, Object t, EventArgs e) +14 System.Web.Util.CalliEventHandlerDelegateProxy.Callback(Object sender, EventArgs e) +35 System.Web.UI.Control.OnLoad(EventArgs e) +99 System.Web.UI.Control.LoadRecursive() +50 System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +627 Thanks to everyone in advance.

  Read the article

• Do you use logical negation operator (!) in "if" statement or check on "== false"

  - by Taras Terebkov

  Hello everyone, I just want to conduct a little survey about code style developers prefer. For me there are two ways to write "if" in such languages as Java, C#, C++, etc. (1) Logical negation operator public void foo() { if (!SessionManager.getInstance().hasActiveSession()) { . . . . . } } (2) Check on "false" public void foo() { if (SessionManager.getInstance().hasActiveSession() == false) { . . . . . } } I always believe that first way is much worst then the second one. Cause usually you don't "read" the code, but "recognize" it in one brief look. And exclamation symbol slipped from your mind, just disturbing you somewhere on the bottom of your unconscious. And only during reading the "if" block below you understand, that the logic is opposite - no sessions in "if" On the other hand in the second way of writing, an eye immediately catches words "SessionManager", "hasActiveSession" and "false". Also for me, the situation with "true" is different. In code like class SessionManager { private bool hasSession; public void foo() { if (hasSession == true) { . . . . . } else { . . . . . } } } I find "true" superfluous. why we repeating the sentence two times? The following is shorter and quicker to catch. class SessionManager { private bool hasSession; public void foo() { if (hasSession) { . . . . . } else { . . . . . } } } What do YOU think, guys?

  Read the article

• PHP Based session variable not retaining value. Works on localhost, but not on server.

  - by Foo

  I've been trying to debug this problem for many hours, but to no avail. I've been using PHP for many years, and got back into it after long hiatus, so I'm still a bit rusty. Anyways, my $_SESSION vars are not retaining their value for some reason that I can't figure out. The site worked on localhost perfectly, but uploading it to the server seemed to break it. First thing I checked was the PHP.ini server settings. Everything seems fine. In fact, my login system is session based and it works perfectly. So now that I know $_SESSIONS are working properly and retaining their value for my login, I'm presuming the server is setup and the problem is in my script. Here's a stripped version of the code that's causing a problem. $type, $order and $style are not being retained after they are set via a GET variable. The user clicks a link, which sets a variable via GET, and this variable is retained for the remainder of their session. Is there some problem with my logic that I'm not seeing? <?php require_once('includes/top.php'); //first line includes a call to session_start(); require_once('includes/db.php'); $type = filter_input(INPUT_GET, 't', FILTER_VALIDATE_INT); $order = filter_input(INPUT_GET, 'o', FILTER_VALIDATE_INT); $style = filter_input(INPUT_GET, 's', FILTER_VALIDATE_INT); /* According to documentation, filter_input returns a NULL when variables are undefined. So, if t, o, or s are not set via URL, $type, $order and $style will be NULL. */ print_r($_SESSION); /* All other sessions, such as the login session, etc. are displayed here. After the sessions are set below, they are displayed up here to... simply with no value. This leads me to believe the problem is with the code below, perhaps? */ // If $type is not null (meaning it WAS set via the get method above) // or it's false because the validation failed for some reason, // then set the session to the $type. I removed the false check for simplicity. // This code is being successfully executed, and the data is being stored... if(!is_null($type)) { $_SESSION['type'] = $type; } if(!is_null($order)) { $_SESSION['order'] = $order; } if(!is_null($style)) { $_SESSION['style'] = $style; } $smarty->display($template); ?> If anyone can point me in the right direction, I'd greatly appreciate it. Thanks.

  Read the article

• Twisted + SQLAlchemy and the best way to do it.

  - by Khorkrak

  So I'm writing yet another Twisted based daemon. It'll have an xmlrpc interface as usual so I can easily communicate with it and have other processes interchange data with it as needed. This daemon needs to access a database. We've been using SQL Alchemy in place of hard coding SQL strings for our latest projects - those mostly done for web apps in Pylons. We'd like to do the same for this app and re-use library code that makes use of SQL Alchemy. So what to do? Well of course since that library was written for use in a Pylons app it's all the straight-forward blocking style code that everyone is accustomed to and all of the non-blocking is magically handled by Pylons via threading, thread locals, scoped sessions and so on. So now for Twisted I guess I'm a bit stuck. I could: Just write the sql I need directly if it's minimal and use the dbapi pool in twisted to do runInteractions etc when I need to hit the db. Use the objects and inherently blocking methods in our library and block now and then in my Twisted daemon. Bah. Use sAsync which was last updated in 2008 and kind of reuse the models we have defined already but not really and it does address code that needs to work in Pylons either. Does that even work with the latest version SQL Alchemy? Who knows. That project looked great though - why was it apparently abandoned? Spawn a separate subprocess and have it deal with the library code and all it's blocking, the results being returned back to my daemon when ready as objects marshalled via YAML over xmlrpc. Use deferToThread and then expunge the objects returned having made sure to do eager loads so that I have all my stuff that I might need. Seems kind of ugha to me. I'm also stuck using Python 2.5.4 atm so no 2.6 yet and I don't think I can just do an import from future to get access to the cool new multiprocessing module stuff in there. That's OK though I guess as we've got dealing with interprocess communication down pretty well. So I'm leaning towards option 4 mostly as that would avoid the mortal sin of logic duplication with option 1 while also staying the heck away from threads. Any better ideas?

  Read the article

• What is the most idiomatic way to emulating Perl's Test::More::done_testing?

  - by DVK

  I have to build unit tests for in environment with a very old version of Test::More (perl5.8 with $Test::More::VERSION being '0.80') which predates the addition of done_testing(). Upgrading to newer Test::More is out of the question for practical reasons. And I am trying to avoid using no_tests - it's generally a bad idea not catching when your unit test exits prematurely - say due to some logic not executing when you expected it to. What is the most idiomatic way of running a configurable amount of tests, assuming no no_tests or done_testing() is used? Details: My unit tests usually take the form of: use Test::More; my @test_set = ( [ "Test #1", $param1, $param2, ... ] ,[ "Test #1", $param1, $param2, ... ] # ,... ); foreach my $test (@test_set) { run_test($test); } sub run_test { # $expected_tests += count_tests($test); ok(test1($test)) || diag("Test1 failed"); # ... } The standard approach of use Test::More tests => 23; or BEGIN {plan tests => 23} does not work since both are obviously executed before @tests is known. My current approach involves making @tests global and defining it in the BEGIN {} block as follows: use Test::More; BEGIN { our @test_set = (); # Same set of tests as above my $expected_tests = 0; foreach my $test (@tests) { my $expected_tests += count_tests($test); } plan tests = $expected_tests; } our @test_set; # Must do!!! Since first "our" was in BEGIN's scope :( foreach my $test (@test_set) { run_test($test); } # Same sub run_test {} # Same I feel this can be done more idiomatically but not certain how to improve. Chief among the smells is the duplicate our @test_test declarations - in BEGIN{} and after it. Another approach is to emulate done_testing() by calling Test::More->builder->plan(tests=>$total_tests_calculated). I'm not sure if it's any better idiomatically-wise.

  Read the article

• How do i know in the detail view what cell in tableview was selected?

  - by Daniel Rotaru

  how can i know what tableview cell was selected?(being in the detail view) The problem is that. I have an table view controller. Here are parsed from the internet entries to the table. So it's a dynamic tabe view that loads from internet. I will not know how many entries will be in the table so i will not know what details view to call when i click a row. So i have maked one view. This view contains an calendar. On this calendar(wich is the detail iew) i will parse data from internet depending on the selected row. For exemple: i have table: entry 1, entry 2,entry 3,entry 4 When i click entry 2 i need to call a php with the argument entry 2. The php will know what entry on the table i have selected and will generate me the correct xml that i will parse. Here is my tableview didSelectRow function: - (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath { // Navigation logic -- create and push a new view controller if(bdvController == nil) bdvController = [[BookDetailViewController alloc] initWithNibName:@"BookDetailView" bundle:[NSBundle mainBundle]]; Villa *aVilla = [appDelegate.villas objectAtIndex:indexPath.row]; [self.navigationController pushViewController:bdvController animated:YES] And here is my self view function on detailviewcontroller: -(void)loadView { [super loadView]; self.title=@"Month" UIBarButtonItem *addButtonItem = [[UIBarButtonItem alloc] initWithTitle:@"ListView" style:UIBarButtonItemStyleDone target:self action:@selector(add:)]; self.navigationItem.rightBarButtonItem = addButtonItem; calendarView = [[[KLCalendarView alloc] initWithFrame:CGRectMake(0.0f, 0.0f, 320.0f, 373.0f) delegate:self] autorelease]; appDelegate1 = (XMLAppDelegate *)[[UIApplication sharedApplication] delegate]; myTableView=[[UITableView alloc]initWithFrame:CGRectMake(0, 260, 320, 160)style:UITableViewStylePlain]; myTableView.dataSource=self; myTableView.delegate=self; UIView *myHeaderView=[[UIView alloc]initWithFrame:CGRectMake(0, 0, myTableView.frame.size.width,2)]; myHeaderView.backgroundColor=[UIColor grayColor]; [myTableView setTableHeaderView:myHeaderView]; [self.view addSubview:myTableView]; [self.view addSubview:calendarView]; [self.view bringSubviewToFront:myTableView]; } I think that here in self load i need to make the if procedure.. If indexPath.row=x parse fisier.php?variabila=title_of_rowx but the question is how i know the indexPath variable?

  Read the article

• How to store array of NSManagedObjects in an NSManagedObject

  - by David Tay

  I am loading my app with a property list of data from a web site. This property list file contains an NSArray of NSDictionaries which itself contains an NSArray of NSDictionaries. Basically, I'm trying to load a tableView of restaurant menu categories each of which contains menu items. My property list file is fine. I am able to load the file and loop through the nodes structure creating NSEntityDescriptions and am able to save to Core Data. Everything works fine and expectedly except that in my menu category managed object, I have an NSArray of menu items for that category. Later on, when I fetch the categories, the pointers to the menu items in a category is lost and I get all the menu items. Am I suppose to be using predicates or does Core Data keep track of my object graph for me? Can anyone look at how I am loading Core Data and point out the flaw in my logic? I'm pretty good with either SQL and OOP by themselves, but am a little bewildered by ORM. I thought that I should just be able to use aggregation in my managed objects and that the framework would keep track of the pointers for me, but apparently not. NSError *error; NSURL *url = [NSURL URLWithString:@"http://foo.com"]; NSArray *categories = [[NSArray alloc] initWithContentsOfURL:url]; NSMutableArray *menuCategories = [[NSMutableArray alloc] init]; for (int i=0; i<[categories count]; i++){ MenuCategory *menuCategory = [NSEntityDescription insertNewObjectForEntityForName:@"MenuCategory" inManagedObjectContext:[self managedObjectContext]]; NSDictionary *category = [categories objectAtIndex:i]; menuCategory.name = [category objectForKey:@"name"]; NSArray *items = [category objectForKey:@"items"]; NSMutableArray *menuItems = [[NSMutableArray alloc] init]; for (int j=0; j<[items count]; j++){ MenuItem *menuItem = [NSEntityDescription insertNewObjectForEntityForName:@"MenuItem" inManagedObjectContext:[self managedObjectContext]]; NSDictionary *item = [items objectAtIndex:j]; menuItem.name = [item objectForKey:@"name"]; menuItem.price = [item objectForKey:@"price"]; menuItem.image = [item objectForKey:@"image"]; menuItem.details = [item objectForKey:@"details"]; [menuItems addObject:menuItem]; } [menuCategory setValue:menuItems forKey:@"menuItems"]; [menuCategories addObject:menuCategory]; [menuItems release]; } if (![[self managedObjectContext] save:&error]) { NSLog(@"An error occurred: %@", [error localizedDescription]); }

  Read the article

• organizing unit test

  - by soulmerge

  I have found several conventions to housekeeping unit tests in a project and I'm not sure which approach would be suitable for our next PHP project. I am trying to find the best convention to encourage easy development and accessibility of the tests when reviewing the source code. I would be very interested in your experience/opinion regarding each: One folder for productive code, another for unit tests: This separates unit tests from the logic files of the project. This separation of concerns is as much a nuisance as it is an advantage: Someone looking into the source code of the project will - so I suppose - either browse the implementation or the unit tests (or more commonly: the implementation only). The advantage of unit tests being another viewpoint to your classes is lost - those two viewpoints are just too far apart IMO. Annotated test methods: Any modern unit testing framework I know allows developers to create dedicated test methods, annotating them (@test) and embedding them in the project code. The big drawback I see here is that the project files get cluttered. Even if these methods are separated using a comment header (like UNIT TESTS below this line) it just bloats the class unnecessarily. Test files within the same folders as the implementation files: Our file naming convention dictates that PHP files containing classes (one class per file) should end with .class.php. I could imagine that putting unit tests regarding a class file into another one ending on .test.php would render the tests much more present to other developers without tainting the class. Although it bloats the project folders, instead of the implementation files, this is my favorite so far, but I have my doubts: I would think others have come up with this already, and discarded this option for some reason (i.e. I have not seen a java project with the files Foo.java and FooTest.java within the same folder.) Maybe it's because java developers make heavier use of IDEs that allow them easier access to the tests, whereas in PHP no big editors have emerged (like eclipse for java) - many devs I know use vim/emacs or similar editors with little support for PHP development per se. What is your experience with any of these unit test placements? Do you have another convention I haven't listed here? Or am I just overrating unit test accessibility to reviewing developers?

  Read the article

• Passing arguments between classes - use public properties or pass a properties class as argument?

  - by devoured elysium

  So let's assume I have a class named ABC that will have a list of Point objects. I need to make some drawing logic with them. Each one of those Point objects will have a Draw() method that will be called by the ABC class. The Draw() method code will need info from ABC class. I can only see two ways to make them have this info: Having Abc class make public some properties that would allow draw() to make its decisions. Having Abc class pass to draw() a class full of properties. The properties in both cases would be the same, my question is what is preferred in this case. Maybe the second approach is more flexible? Maybe not? I don't see here a clear winner, but that sure has more to do with my inexperience than any other thing. If there are other good approaches, feel free to share them. Here are both cases: class Abc1 { public property a; public property b; public property c; ... public property z; public void method1(); ... public void methodn(); } and here is approach 2: class Abc2 { //here we make take down all properties public void method1(); ... public void methodn(); } class Abc2MethodArgs { //and we put them here. this class will be passed as argument to //Point's draw() method! public property a; public property b; public property c; ... public property z; } Also, if there are any "formal" names for these two approaches, I'd like to know them so I can better choose the tags/thread name, so it's more useful for searching purposes. That or feel free to edit them.

  Read the article

• Achieving C# "readonly" behavior in C++

  - by Tommy Fisk

  Hi guys, this is my first question on stack overflow, so be gentle. Let me first explain the exact behavior I would like to see. If you are familiar with C# then you know that declaring a variable as "readonly" allows a programmer to assign some value to that variable exactly once. Further attempts to modify the variable will result in an error. What I am after: I want to make sure that any and all single-ton classes I define can be predictably instantiated exactly once in my program (more details at the bottom). My approach to realizing my goal is to use extern to declare a global reference to the single-ton (which I will later instantiate at a time I choose. What I have sort of looks like this, namespace Global { extern Singleton& mainInstance; // not defined yet, but it will be later! } int main() { // now that the program has started, go ahead and create the singleton object Singleton& Global::mainInstance = Singleton::GetInstance(); // invalid use of qualified name Global::mainInstance = Singleton::GetInstance(); // doesn't work either :( } class Singleton { /* Some details ommited */ public: Singleton& GetInstance() { static Singleton instance; // exists once for the whole program return instance; } } However this does not really work, and I don't know where to go from here. Some details about what I'm up against: I'm concerned about threading as I am working on code that will deal with game logic while communicating with several third-party processes and other processes I will create. Eventually I would have to implement some kind of synchronization so multiple threads could access the information in the Singleton class without worry. Because I don't know what kinds of optimizations I might like to do, or exactly what threading entails (never done a real project using it), I was thinking that being able to predictably control when Singletons were instantiated would be a Good Thing. Imagine if Process A creates Process B, where B contains several Singletons distributed against multiple files and/or libraries. It could be a real nightmare if I can not reliably ensure the order these singleton objects are instantiated (because they could depend on each other, and calling methods on a NULL object is generally a Bad Thing). If I were in C# I would just use the readonly keyword, but is there any way I can implement this (compiler supported) behavior in C++? Is this even a good idea? Thanks for any feedback.

  Read the article

• Hot to get rid of memory allocations/deallocations in swig wrappers?

  - by Dmitriy Matveev

  I want to use swig for generation of read-only wrappers for a complex object. The object which I want to wrap will always be existent while I will read it. And also I will only use my wrappers at the time that object is existent, thus I don't need any memory management from SWIG. For following swig interface: %module test %immutable; %inline %{ struct Foo { int a; }; struct Bar { int b; Foo f; }; %} I will have a wrappers which will have a lot of garbage in generated interfaces and do useless work which will reduce performance in my case. Generated java wrapper for Bar class will be like this: public class Bar { private long swigCPtr; protected boolean swigCMemOwn; protected Bar(long cPtr, boolean cMemoryOwn) { swigCMemOwn = cMemoryOwn; swigCPtr = cPtr; } protected static long getCPtr(Bar obj) { return (obj == null) ? 0 : obj.swigCPtr; } protected void finalize() { delete(); } public synchronized void delete() { if (swigCPtr != 0) { if (swigCMemOwn) { swigCMemOwn = false; testJNI.delete_Bar(swigCPtr); } swigCPtr = 0; } } public int getB() { return testJNI.Bar_b_get(swigCPtr, this); } public Foo getF() { return new Foo(testJNI.Bar_f_get(swigCPtr, this), true); } public Bar() { this(testJNI.new_Bar(), true); } } I don't need 'swigCMemOwn' field in my wrapper since it always will be false. All code related to this field will also be useless. There are also unnecessary logic in native code: SWIGEXPORT jlong JNICALL Java_some_testJNI_Bar_1f_1get(JNIEnv *jenv, jclass jcls, jlong jarg1, jobject jarg1_) { jlong jresult = 0 ; struct Bar *arg1 = (struct Bar *) 0 ; Foo result; (void)jenv; (void)jcls; (void)jarg1_; arg1 = *(struct Bar **)&jarg1; result = ((arg1)->f); { Foo * resultptr = (Foo *) malloc(sizeof(Foo)); memmove(resultptr, &result, sizeof(Foo)); *(Foo **)&jresult = resultptr; } return jresult; } I don't need these calls to malloc and memmove. I want to force swig to resolve both of these problems, but don't know how. Is it possible?

  Read the article

• Can I use WCF to replace my current Web Service and Window Service combination?

  - by gun_shy

  I need a little bit of advise regarding the situation I am faced with. The current arrangement I have been tasked with improving just doesn't sit well with me and I feel like there is a better way to do it. The more I read about WCF, the more I get the feeling that it might be what I am looking for. Right now, I have an asp.net client, a .net web service, a windows service, a ms sql database, and a third party application that is used for processing a group of 'project' files into a finalized file. Since the third party application can only handle processing one 'project' at a time, the combination of the web service, window service, and database have been arranged to create a job queue manager for the third party application. The client sends a zip 'project' file containing multiple sub files to the web service. The web service adds a new 'project' line to the database, generating a unique job id. The zip file is expanded to a folder location on the server using the job id as the folder name. The web service then returns the job id to the client. The client will use this id to poll the web service for the status of the job submitted. When the job is complete, the client will request the processed file. The windows service polls the database every x minutes. If a new job exists, the service will pull the oldest job and send it to the third party app for processing. If the processing succeeds, the window service updates the project line in the database, marking the job complete. The window service will continue to process any non complete jobs in the database until there are no more. When it stops finding any jobs, it will sleep x minutes and then poll the database again. I do not like the fact that the window service has to poll the database. If there is only one job submitted, the client will have to wait for the window service to poll and then wait while the 'project' is being processed. It seems like WCF could be used to combine the web and window services using a combination of the InstanceContextMode.Single and ConcurrencyMode.Multiple. So far, I have been unable to find any articles or examples that would point me in the right direction. Can WCF be utilized to accomplish the job queue logic of the current arrangement in a better way? As always, any help is more than appreciated.

  Read the article

• Boxy Submit Form

  - by jornbjorndalen

  I am using the boxy jQuery plugin in my page to display a form on a clickEvent for the fullCalendar plugin. It is working all right , the only problem I have is that the form in boxy brings up the confirmation dialog the first time the dialog is opened and when the user clicks "Ok" it submits the form a second time which generates 2 events on my calendar and 2 entries in my database. My code looks like this inside fullCalendar: dayClick: function(date, allDay, jsEvent, view) { var day=""+date.getDate(); if(day.length==1){ day="0"+day; } var year=date.getFullYear(); var month=date.getMonth()+1; var month=""+month; if(month.length==1){ month="0"+month; } var defaultdate=""+year+"-"+month+"-"+day+" 00:00:00"; var ele = document.getElementById("myform"); new Boxy(ele,{title: "Add Task", modal: true}); document.getElementById("title").value=""; document.getElementById("description").value=""; document.getElementById("startdate").value=""+defaultdate; document.getElementById("enddate").value=""+defaultdate; } I also use validators on the forms fields: $.validator.addMethod( "datetime", function(value, element) { // put your own logic here, this is just a (crappy) example return value.match(/^([0-9]{4})-([0-1][0-9])-([0-3][0-9])\s([0-1][0-9]|[2][0-3]):([0-5][0-9]):([0-5][0-9])$/); }, "Please enter a date in the format YYYY-mm-dd hh:MM:ss" ); var validator=$("#myform").validate({ onsubmit:true, rules: { title: { required: true }, startdate: { required: true, datetime: true }, enddate: { required: true, datetime: true } }, submitHandler: function(form) { //this function renders a new event and makes a call to a php script that inserts it into the db addTask(form); } }); And the form looks like this: <form id ='myform'> <table border='1' width='100%'> <tr><td align='right'>Title:</td><td align='left'><input id='title' name='title' size='30'/></td></tr> <tr><td align='right'>Description:</td><td align='left'><textarea id='description' name='description' rows='4' cols='30'></textarea></td></tr> <tr><td align='right'>Start Date:</td><td align='left'><input id='startdate' name='startdate' size='30'/></td></tr> <tr><td align='right'>End Date:</td><td align='left'><input id='enddate' name='enddate' size='30' /></td></tr> <tr><td colspan='2' align='right'><input type='submit' value='Add' /></td></tr> </table> </form>

  Read the article

• Representation of a DateTime as the local to remote user

  - by TwoSecondsBefore

  Hello! I was confused in the problem of time zones. I am writing a web application that will contain some news with dates of publication, and I want the client to see the date of publication of the news in the form of corresponding local time. However, I do not know in which time zone the client is located. I have three questions. I have to ask just in case: does DateTimeOffset.UtcNow always returns the correct UTC date and time, regardless of whether the server is dependent on daylight savings time? For example, if the first time I get the value of this property for two minutes before daylight savings time (or before the transition from daylight saving time back) and the second time in 2 minutes after the transfer, whether the value of properties in all cases differ by only 4 minutes? Or here require any further logic? (Question #1) Please see the following example and tell me what you think. I posted the news on the site. I assume that DateTimeOffset.UtcNow takes into account the time zone of the server and the daylight savings time, and so I immediately get the correct UTC server time when pressing the button "Submit". I write this value to a MS SQL database in the field of type datetime2(0). Then the user opens a page with news and no matter how long after publication. This may occur even after many years. I did not ask him to enter his time zone. Instead, I get the offset of his current local time from UTC using the javascript function following way: function GetUserTimezoneOffset() { var offset = new Date().getTimezoneOffset(); return offset; } Next I make the calculation of the date and time of publication, which will show the user: public static DateTime Get_Publication_Date_In_User_Local_DateTime( DateTime Publication_Utc_Date_Time_From_DataBase, int User_Time_Zone_Offset_Returned_by_Javascript) { int userTimezoneOffset = User_Time_Zone_Offset_Returned_by_Javascript; // For // example Javascript returns a value equal to -300, which means the // current user's time differs from UTC to 300 minutes. Ie offset // is UTC +6. In this case, it may be the time zone UTC +5 which // currently operates summer time or UTC +6 which currently operates the // standard time. // Right? (Question #2) DateTimeOffset utcPublicationDateTime = new DateTimeOffset(Publication_Utc_Date_Time_From_DataBase, new TimeSpan(0)); // get an instance of type DateTimeOffset for the // date and time of publication for further calculations DateTimeOffset publication_DateTime_In_User_Local_DateTime = utcPublicationDateTime.ToOffset(new TimeSpan(0, - userTimezoneOffset, 0)); return publication_DateTime_In_User_Local_DateTime.DateTime;// return to user } Is the value obtained correct? Is this the right approach to solving this problem? (Question #3)

  Read the article

• Adding a clustered index to a SQL table: what dangers exist for a live production system?

  - by MoSlo

  Right, keep in mind i need to describe this by abstracting all possible confidential info: I've been put in charge of a 10-year old transactional system of which the majority business logic is implemented at database level (triggers, stored procedures etc). Win2000 server, MSSQL 2000 Enterprise. No immediate plans for replacing/updating the system are being considered :( The core process is a program that executes transactions - specifically, it executes a stored procedure with various parameters, lets call it sp_ProcessTrans. The program executes the stored procedure at asynchronous intervals. By itself, things work fine. But there are 30 instances of this program on remotely located workstations, all of them asynchronously executing sp_ProcessTrans and then retrieving data from the SQL server (execution is pretty regular - ranging 0 to 60 times a minute, depending on what items the program instance is responsible for) . Performance of the system has dropped considerably with 10 yrs of data growth: the reason is the deadlocks and specifically deadlock wait times. The deadlock is on the Employee table. I have discovered: In sp_ProcessTrans' execution, it selects from an Employee table 7 times (dont ask) The select is done on a field that is NOT the primary key No index exists on this field. Thus a table scan is performed. 7 times. per transaction So the reason for deadlocks is clear. I created a non-unique ordered clustered index on the field (field looks good, almost unique, NUM(7), very rarely changes). Immediate improvement in the test environment. The problem is that i cannot simulate the deadlocks in a test environment (I'd need 30 workstations; i'd need to simulate 'realistic' activity on those stations, so visualization is out). I need to know if i must schedule downtime. Creating an index shouldn't be a risky operation for MSSQL, but is there any danger (data corruption in transactions/select statements/extra wait time etc) to create this field index on the production database while the transactions are still taking place? (although i can select a time when transactions are fairly quiet through the 30 stations) Are there any hidden dangers i'm not seeing (not looking forward to needing to restore the DB if something goes wrong, restoring would take a lot of time with 10yrs of data).

  Read the article

• Can you call FB.login inside a callback from other FB methods (like FB.getLoginStatus) without triggering popup blockers?

  - by Erik Kallevig

  I'm trying to set up a pretty basic authentication logic flow with the FB JavaScript SDK to check a user's logged-in status and permissions before performing an action (and prompting the user to login with permissions if they are not)... User types a message into a textarea on my site to post to their Facebook feed and click's a 'post to facebook' button on my site. In response to the click, I check user's logged in status with FB.getLoginStatus In the callback to FB.getLoginStatus, if user is not logged in, prompt them to login (FB.login). In the callback to FB.login I then need to make sure they have the right permissions so I make a call to FB.api('/me/permissions') -- if they don't , I again prompt them to login (FB.login) The problem I'm running into is that anytime I try to call FB.login inside a callback to other FB methods, the browser seems to lose track of the origin of execution (the click) and thus will block the popup. I'm wondering if I'm missing some way to prompt the user to login after checking their status without the browser mistakenly thinking that it's not a user-initiated popup? I've currently fallen back to just calling FB.login() first regardless. The undesired side effect of this approach, however, is that if the user is already logged-in with permissions and I'm still calling FB.login, the auth popup will open and close immediately before continuing, which looks rather buggy despite being functional. It seems like checking a user's login status and permissions before doing something would be a common flow so I feel like I'm missing something. Here's some example code. <div onclick="onClickPostBtn()">Post to Facebook</div> <script> // Callback to click on Post button. function onClickPostBtn() { // Check if logged in, prompt to do so if not. FB.getLoginStatus(function(response) { if (response.status === 'connected') { checkPermissions(response.authResponse.accessToken); } else { FB.login(function(){}, {scope: 'publish_stream'}) } }); } // Logged in, check permissions. function checkPermissions(accessToken) { FB.api('/me/permissions', {'access_token': accessToken}, function(response){ // Logged in and authorized for this site. if (response.data && response.data.length) { // Parse response object to check for permission here... if (hasPermission) { // Logged in with permission, perform some action. } else { // Logged in without proper permission, request login with permissions. FB.login(function(){}, {scope: 'publish_stream'}) } // Logged in to FB but not authorized for this site. } else { FB.login(function(){}, {scope: 'publish_stream'}) } } ); } </script>

  Read the article

• Adding different data to different jquery tabs

  - by Sarah

  i have 2 functions 1- addMessage(): save data into database and is called only on click . 2-updateMessage():get data with ajax from database, called when document is ready ,called every 3 seconds for new data, and called on success of addMessage(). function updateMessage() { $.ajax({ url:"db.php", type:"post", dataType:"text/xml", success:function(data) { $(data).find("message").each(function() { var msg_id = $(this).find("msg_id").text(); var date_time = $(this).find("date_time").text(); var from_user = $(this).find("from_user").text(); var from_group = $(this).find("from_group").text(); var to_user = $(this).find("to_user").text(); var to_group = $(this).find("to_group").text(); var msg_type = $(this).find("msg_type").text(); var msg = $(this).find("msg").text(); var grp_abr = $(this).find("grp_abr").text(); var html = "<tr class='blue'>"; html += "<td><a href='#' class='bullet' onclick='changeStatus(\""+msg_id+"\")'><\/a><\/td>"; html += "<td><a href='#' class='reply' onclick='reply(\""+from_user+"\");'><\/a><\/td>"; html += "<td>"+date_time+"<\/td>"; html += "<td>"+from_user+"["+from_group+"]"+"<\/td>"; html += "<td>"+to_user+"["+to_group+"]"+"<\/td>"; html += "<td><a href='#' class="+msg_type+"><\/a><\/td>"; html += "<td><a href='#' class='flag_msg' onclick='flagMsg("+msg_id+")'><\/a><\/td>"; html += "<td>"+msg_id+msg+"<\/td>"; html += "<td>"+grp_abr+"<\/td><\/tr>"; }); } }); setTimeout('updateMessage()',3000); } Now the data retrieved i want to add to different tabs with different names and different containers, how would i do that. My question isn't a matter of code, it is more about logic or sequence of steps. Any help please.

  Read the article

• PHP MSSQL : How to display output when query return no row

  - by vamps

  i have a problem with my PHP-MSSQL query. i have a join table that need to give a result something be like this: Department Group A Group B Total A+B WORKHOUR A OTHOUR A WORKHOUR B OTHOUR B WORKHOUR OTHOUR HR 10 15 25 0 35 15 IT 5 5 5 5 Admin 12 12 12 12 the query will count how many employee as per given date (admin will enter data and once submitted, the query will give the above result). The problem is, the final output is a mess when there's no row to be displayed. the column is shifted to the right. i.e: only Group A in IT only Group B in Admin Department Group A Group B Total A+B WORKHOUR A OTHOUR A WORKHOUR B OTHOUR B WORKHOUR OTHOUR HR 10 15 25 0 35 15 IT 5 5 5 5 Admin 12 12 12 12 my question is, how to prevent this to happen? i've tried everything with While.... if else.. but the result is still the same. how to display output "0" if no rows to return? echo "0"; this is my QUERY: select DD.DPT_ID,DPT.DEPARTMENT_NAME,TU.EMP_GROUP, sum(DD.WORK_HOUR) AS WORK_HOUR, sum(DD.OT_HOUR) AS OT_HOUR FROM DEPARTMENT_DETAIL DD left join DEPARTMENT DPT ON (DD.DEPT_ID=DPT.DEPT_ID) LEFT JOIN TBL_USERS TU ON (TU.EMP_ID=DD.EMP_ID) WHERE DD_DATE>='2012-01-01' AND DD_DATE<='2012-01-31' AND TU.EMP_GROUP!=2 GROUP BY DD.DEPT_ID, DPT.DEPARTMENT_NAME,TU.EMP_GROUP ORDER BY DPT.DEPARTMENT_NAME this is one of the logic that i've used, but doesn't return the result that i want:: while($row = mssql_fetch_array($displayResult)) { if ((!$row["WORK_HOUR"])&&(!$row["OT_HOUR"])) { echo "<td >"; echo "empty"; echo "&nbsp;</td>"; echo "<td >"; echo "empty"; echo "&nbsp;</td>"; } else { echo "<td>"; echo $row["WORK_HOUR"]; echo "&nbsp;</td>"; echo "<td>"; echo $row["OT_HOUR"]; echo "&nbsp;</td>"; } } please help. i've been doing this for 2 days. @__@

  Read the article

• Guilty of unsound programming

  - by TelJanini

  I was reading Robert Rossney's entry on "What's the most unsound program you've had to maintain?" found at: (What's the most unsound program you've had to maintain?) when I realized that I had inadvertently developed a near-identical application! The app consists of an HTTPListener object that grabs incoming POST requests. Based on the information in the header, I pass the body of the request to SQL Server to perform the appropriate transaction. The requests look like: <InvoiceCreate Control="389> <Invoice> <CustomerNumber>5555</CustomerNumber> <Total>300.00</Total> <RushOrder>1</RushOrder> </Invoice> </InvoiceCreate> Once it's received by the HTTPListener object, I perform the required INSERT to the Invoice table using SQL Server's built-in XML handling functionality via a stored procedure: INSERT INTO Invoice (InvoiceNumber, CustomerNumber, Total, RushOrder) SELECT @NEW_INVOICE_NUMBER, @XML.value('(InvoiceCreate/Invoice/CustomerNumber)[1]', 'varchar(10)'), @XML.value('(InvoiceCreate/Invoice/Total)[1]', 'varchar(10)'), @XML.value('(InvoiceCreate/Invoice/Total)[1]', 'varchar(10)') I then use another SELECT statement in the same stored procedure to return the value of the new Invoice Number that was inserted into the Invoices table: SELECT @NEW_INVOICE_NUMBER FOR XML PATH 'InvoiceCreateAck' I then read the generated XML using a SQL data reader object in C# and use it as the response of the HTTPListener object. My issue is, I'm noticing that Robert is indeed correct. All of my application logic exists inside the stored procedure, so I find myself having to do a lot of error-checking (i.e. validating the customer number and invoicenumber values) inside the stored procedure. I'm still a midlevel developer, and as such, am looking to improve. Given the original post, and my current architecture, what could I have done differently to improve the application? Are there any patterns or best practices that I could refer to? What approach would you have taken? I'm open to any and all criticism, as I'd like to do my part to reduce the amount of "unsound programming" in the world.

  Read the article

• Remove Item From Object SubList (LINQ)

  - by X3074861X

  I have an object that looks like this : public class Consortium { public string Id { get; set; } [JsonConverter(typeof(EnumDescriptionConverter))] public SourceType Type { get; set; } public List<UserLibrary> Branches { get; set; } } Each Consortium has a list of UserLibrary's associated with it, and that class looks like this : public class UserLibrary { public string LibraryId { get; set; } public string RetailerId {get; set;} public string UserId { get; set; } public string Name { get; set; } public DateTime CreatedAt { get; set; } } I have a method which will allow the user to remove a library from one of their consortium (note: There may be many branches associated to the consortium). However, I'm only being supplied a LibraryId, so I'm forced to traverse their list of Consortium, find which one contains the given id, then iterate over the branches and remove the one that matches the id. Here is how I'm currently accomplishing this : // Get the current list of consortiums var user = _mediator.Send(new GetUserProfileCommand { UserProfileId = _principle.UserProfileId }); var userConsortia = user.SavedConsortia; // the consortium to remove the library from var branchToRemove = _libraryService.GetLibrary(id); var consortRemove = new UserConsortium(); foreach (var userConsortium in userConsortia) { if (userConsortium.Branches.FirstOrDefault(c => string.Equals(c.LibraryId, id, StringComparison.OrdinalIgnoreCase)) != null) { consortRemove = userConsortium; } } // if the consortium id is null, something is f* if (consortRemove.Id == null) { return new JsonDotNetResult(HttpStatusCode.BadRequest); } // first remove the consortia userConsortia.Remove(consortRemove); // remove the branch from the consortium consortRemove.Branches.RemoveAll(ul => string.Equals(ul.LibraryId, id, StringComparison.OrdinalIgnoreCase)); // add it back in without the branch userConsortia.Add(consortRemove); Question : Is there a LINQ expression I'm missing here that can help me consolidate this logic, or is there a better way of doing this?

  Read the article

• Correct use of a "for...in" loop in javascript?

  - by jnkrois

  Hello everybody, before I ask my question I wanted to let everybody know that I appreciate the fact that there's always somebody out there willing to help, and on my end I'll try to give back to the community as much as I can. Thanks Now, I would like to get some pointers as to how to properly take advantage of the "for...in" loop in JavaScript, I already did some research and tried a couple things but it is still not clear to me how to properly use it. Let's say I have a random number of "select" tags in an HTML form, and I don't require the user to select an option for all of them, they can leave some untouched if they want. However I need to know if they selected none or at least one. The way I'm trying to find out if the user selected any of them is by using the "for...in" loop. For example: var allSelected = $("select option:selected"); var totalSelected = $("select option:selected").length; The first variable produces an array of all the selected options. The second variable tells me how many selected options I have in the form (select tags could be more than one and it changes every time). Now, in order to see if any has been selected I loop through each element (selected option), and retrieve the "value" attribute. The default "option" tag has a value="0", so if any selected option returns a value greater than 0, I know at least one option has been selected, however it does not have to be in order, this is my loop so far: for(var i = 0; i < totalSelected; i++){ var eachOption = $(allSelected[i]).val(); var defaultValue = 0; if(eachOption == defaultValue){ ...redirect to another page }else if(eachOption > defaultValue){ ... I display an alert } } My problem here is that as soon as the "if" matches a 0 value, it sends the user to the next page without testing the rest of the elements in the array, and the user could have selected the second or third options. What I really want to do is check all the elements in the array and then take the next action, in my mind this is how I could do it, but I'm not getting it right: var randomValue = 25; for(randomValue in allSelected){ var found = true; var notFound = false if(found){ display an alert }else{ redirect to next page } } This loop or the logic I'm using are flawed (I'm pretty sure), what I want to do is test all the elements in the array against a single variable and take the next action accordingly. I hope this makes some sense to you guys, any help would be appreciated. Thanks, JC

  Read the article

• What's the best way to handle modules that use each other?

  - by Axeman

  What's the best way to handle modules that use each other? Let's say I have a module which has functions for hashes: # Really::Useful::Functions::On::Hash.pm use base qw<Exporter>; use strict; use warnings; use Really::Useful::Functions::On::List qw<transform_list>; our @EXPORT_OK = qw<transform_hash transform_hash_as_list ...>; #... sub transform_hash { ... } #... sub transform_hash_as_list { return transform_list( %{ shift() } ); } #... 1 And another module has been segmented out for lists: # Really::Useful::Functions::On::List.pm use base qw<Exporter>; use strict; use warnings; use Really::Useful::Functions::On::Hash qw<transform_hash>; our @EXPORT_OK = qw<transform_list some_func ...>; #... sub transform_list { ... } #... sub some_func { my %params = transform_hash @_; #... } #... 1 Suppose that enough of these utility functions are handy enough that I'll want to use them in BEGIN statements and import functions to process parameter lists or configuration data. I have been putting sub definitions into BEGIN blocks to make sure they are ready to use whenever somebody includes the module. But I have gotten into hairy race conditions where a definition is not completed in a BEGIN block. I put evolving code idioms into modules so that I can reuse any idiom I find myself coding over and over again. For instance: sub list_if { my $condition = shift; return unless $condition; my $more_args = scalar @_; my $arg_list = @_ > 1 ? \@_ : @_ ? shift : $condition; if (( reftype( $arg_list ) || '' ) eq 'ARRAY' ) { return wantarray ? @$arg_list : $arg_list; } elsif ( $more_args ) { return $arg_list; } return; } captures two idioms that I'm kind of tired of typing: @{ func_I_hope_returns_a_listref() || [] } and ( $condition ? LIST : ()) The more I define functions in BEGIN blocks, the more likely I'll use these idiom bricks to express the logic the more likely that bricks are needed in BEGIN blocks. Do people have standard ways of dealing with this sort of language-idiom-brick model? I've been doing mostly Pure-Perl; will XS alleviate some of this?

  Read the article

< Previous Page | 178 179 180 181 182 183 184 185 186 187 188 189  | Next Page >