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  • actionscript-3: refactor interface inheritance to get rid of ambiguous reference error

    - by maxmc
    hi! imagine there are two interfaces arranged via composite pattern, one of them has a dispose method among other methods: interface IComponent extends ILeaf { ... function dispose() : void; } interface ILeaf { ... } some implementations have some more things in common (say an id) so there are two more interfaces: interface ICommonLeaf extends ILeaf { function get id() : String; } interface ICommonComponent extends ICommonLeaf, IComponent { } so far so good. but there is another interface which also has a dispose method: interface ISomething { ... function dispose() : void; } and ISomething is inherited by ICommonLeaf: interface ICommonLeaf extends ILeaf, ISomething { function get id() : String; } As soon as the dispose method is invoked on an instance which implements the ICommonComponent interface, the compiler fails with an ambiguous reference error because ISomething has a method called dispose and ILeaf also has a dispose method, both living in different interfaces (IComponent, ISomething) within the inheritace tree of ICommonComponent. I wonder how to deal with the situation if the IComponent, the ILeaf and the ISomething can't change. the composite structure must also work for for the ICommonLeaf & ICommonComponent implementations and the ICommonLeaf & ICommonComponent must conform to the ISomething type. this might be an actionscript-3 specific issue. i haven't tested how other languages (for instance java) handle stuff like this.

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  • How to replace custom IDs in the order of their appearance with a shell script?

    - by Péter Török
    I have a pair of rather large log files with very similar content, except that some identifiers are different between the two. A couple of examples: UnifiedClassLoader3@19518cc | UnifiedClassLoader3@d0357a JBossRMIClassLoader@13c2d7f | JBossRMIClassLoader@191777e That is, wherever the first file contains UnifiedClassLoader3@19518cc, the second contains UnifiedClassLoader3@d0357a, and so on. I want to replace these with identical IDs so that I can spot the really important differences between the two files. I.e. I want to replace all occurrences of both UnifiedClassLoader3@19518cc in file1 and UnifiedClassLoader3@d0357a in file2 with UnifiedClassLoader3@1; all occurrences of both JBossRMIClassLoader@13c2d7f in file1 and JBossRMIClassLoader@191777e in file2 with JBossRMIClassLoader@2 etc. Using the Cygwin shell, so far I managed to list all different identifiers occurring in one of the files with grep -o -e 'ClassLoader[0-9]*@[0-9a-f][0-9a-f]*' file1.log | sort | uniq However, now the original order is lost, so I don't know which is the pair of which ID in the other file. With grep -n I can get the line number, so the sort would preserve the order of appearance, but then I can't weed out the duplicate occurrences. Unfortunately grep can not print only the first match of a pattern. I figured I could save the list of identifiers produced by the above command into a file, then iterate over the patterns in the file with grep -n | head -n 1, concatenate the results and sort them again. The result would be something like 2 ClassLoader3@19518cc 137 ClassLoader@13c2d7f 563 ClassLoader3@1267649 ... Then I could (either manually or with sed itself) massage this into a sed command like sed -e 's/ClassLoader3@19518cc/ClassLoader3@2/g' -e 's/ClassLoader@13c2d7f/ClassLoader@137/g' -e 's/ClassLoader3@1267649/ClassLoader3@563/g' file1.log > file1_processed.log and similarly for file2. However, before I start, I would like to verify that my plan is the simplest possible working solution to this. Is there any flaw in this approach? Is there a simpler way?

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  • Two questions on ensuring EndInvoke() gets called on a list of IAsyncResult objects

    - by RobV
    So this question is regarding the .Net IAsyncResult design pattern and the necessity of calling EndInvoke as covered in this question Background I have some code where I'm firing off potentially many asynchronous calls to a particular function and then waiting for all these calls to finish before using EndInvoke() to get back all the results. Question 1 I don't know whether any of the calls has encountered an exception until I call EndInvoke() and in the event that an exception occurs in one of the calls the entire method should fail and the exception gets wrapped into an API specific exception and thrown upwards. So my first question is what's the best way then to ensure that the remainder of the async calls get properly terminated? Is a finally block which calls EndInvoke() on the remainder of the unterminated calls (and ignores any further exceptions) the best way to do this? Question 2 Secondly when I first fire off all my asyc calls I then call WaitHandle.WaitAll() on the array of WaitHandle instances that I've got from my IAsyncResult instances. The method which is firing all these async calls has a timeout to adhere to so I provide this to the WaitAll() method. Then I test whether all the calls have completed, if not then the timeout must have been reached so the method should also fail and throw another API specific exception. So my second question is what should I do in this case? I need to call EndInvoke() to terminate all these async calls before I throw the error but at the same time I don't want the code to get stuck since EndInvoke() is blocking. In theory at least if the WaitAll() call times out then all the async calls should themselves have timed out and thrown exceptions (thus completing the call) since they are also governed by a timeout but this timeout is potentially different from the main timeout

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  • JSF how to temporary disable validators to save draft

    - by Swiety
    I have a pretty complex form with lots of inputs and validators. For the user it takes pretty long time (even over an hour) to complete that, so they would like to be able to save the draft data, even if it violates rules like mandatory fields being not typed in. I believe this problem is common to many web applications, but can't find any well recognised pattern how this should be implemented. Can you please advise how to achieve that? For now I can see the following options: use of immediate=true on "Save draft" button doesn't work, as the UI data would not be stored on the bean, so I wouldn't be able to access it. Technically I could find the data in UI component tree, but traversing that doesn't seem to be a good idea. remove all the fields validation from the page and validate the data programmaticaly in the action listener defined for the form. Again, not a good idea, form is really complex, there are plenty of fields so validation implemented this way would be very messy. implement my own validators, that would be controlled by some request attribute, which would be set for standard form submission (with full validation expected) and would be unset for "save as draft" submission (when validation should be skipped). Again, not a good solution, I would need to provide my own wrappers for all validators I am using. But as you see no one is really reasonable. Is there really no simple solution to the problem?

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  • Setting javascript prototype function within object class declaration

    - by Tauren
    Normally, I've seen prototype functions declared outside the class definition, like this: function Container(param) { this.member = param; } Container.prototype.stamp = function (string) { return this.member + string; } var container1 = new Container('A'); alert(container1.member); alert(container1.stamp('X')); This code produces two alerts with the values "A" and "AX". I'd like to define the prototype function INSIDE of the class definition. Is there anything wrong with doing something like this? function Container(param) { this.member = param; if (!Container.prototype.stamp) { Container.prototype.stamp = function() { return this.member + string; } } } I was trying this so that I could access a private variable in the class. But I've discovered that if my prototype function references a private var, the value of the private var is always the value that was used when the prototype function was INITIALLY created, not the value in the object instance: Container = function(param) { this.member = param; var privateVar = param; if (!Container.prototype.stamp) { Container.prototype.stamp = function(string) { return privateVar + this.member + string; } } } var container1 = new Container('A'); var container2 = new Container('B'); alert(container1.stamp('X')); alert(container2.stamp('X')); This code produces two alerts with the values "AAX" and "ABX". I was hoping the output would be "AAX" and "BBX". I'm curious why this doesn't work, and if there is some other pattern that I could use instead.

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  • Using clases in PHP to store function

    - by Artur
    Hello! I need some advise on my PHP code organisation. I need classes where I can store different functions, and I need access to those classes in different parts of my project. Making an object of this classes each time is too sadly, so I've found a two ways have to solve it. First is to use static methods, like class car { public static $wheels_count = 4; public static function change_wheels_count($new_count) { car::$wheels_count = $new_count; } } Second is to use singleton pattern: class Example { // Hold an instance of the class private static $instance; // The singleton method public static function singleton() { if (!isset(self::$instance)) { $c = __CLASS__; self::$instance = new $c; } return self::$instance; } } But author of the article about singletons said, that if I have too much singletons in my code I should reconstruct it. But I need a lot of such classes. Can anybody explain prons and cons of each way? Which is mostly used? Are there more beautiful ways?

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  • a selective dual command binding converter in WPF?

    - by Jippers
    I'll start off and say I am not using the MVVM pattern for my WPF app. Please forgive me. Right now I have a data template with two buttons, each binds to a different command on the CLR object this data template represents. Both use the same command parameter. Here's an example of the buttons. <Button x:Name="Button1" Command="{Binding Path=Command1}" CommandParameter="{Binding Path=Text, ElementName=TextBox1}" /> <Button x:Name="Button2" Command="{Binding Path=Command2}" CommandParameter="{Binding Path=Text, ElementName=TextBox1}" /> I would like to refactor this into a single button that can perform either command based on a user setting like a boolean in Settings.settings. I don't have access to refactoring the CLR object itself. Also this is a Data Template there isn't codebehind for me to work with. My take is that a converter would be the best bet, but I don't know how I would put that together. The converter would need to take in the CommandParameter, as well as the DataContext so it knows which object to execute the Commands on. Can someone lend me a hand with this? Thanks in advance.

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  • Hibernate database integrity with multiple java applications

    - by Austen
    We have 2 java web apps both are read/write and 3 standalone java read/write applications (one loads questions via email, one processes an xml feed, one sends email to subscribers) all use hibernate and share a common code base. The problem we have recently come across is that questions loaded via email sometimes overwrite questions created in one of the web apps. We originally thought this to be a caching issue. We've tried turning off the second level cache, but this doesn't make a difference. We are not explicitly opening and closing sessions, but rather let hibernate manage them via Util.getSessionFactory().getCurrentSession(), which thinking about it, may actually be the issue. We'd rather not setup a clustered 2nd level cache at this stage as this creates another layer of complexity and we're more than happy with the level of performance we get from the app as a whole. So does implementing a open-session-in-view pattern in the web apps and manually managing the sessions in the standalone apps sound like it would fix this? Or any other suggestions/ideas please? <property name="hibernate.transaction.factory_class">org.hibernate.transaction.JDBCTransactionFactory</property> <property name="hibernate.current_session_context_class">thread</property> <property name="hibernate.cache.use_second_level_cache">false</property>

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  • Using Sub-Types And Return Types in Scala to Process a Generic Object Into a Specific One

    - by pr1001
    I think this is about covariance but I'm weak on the topic... I have a generic Event class used for things like database persistance, let's say like this: class Event( subject: Long, verb: String, directobject: Option[Long], indirectobject: Option[Long], timestamp: Long) { def getSubject = subject def getVerb = verb def getDirectObject = directobject def getIndirectObject = indirectobject def getTimestamp = timestamp } However, I have lots of different event verbs and I want to use pattern matching and such with these different event types, so I will create some corresponding case classes: trait EventCC case class Login(user: Long, timestamp: Long) extends EventCC case class Follow( follower: Long, followee: Long, timestamp: Long ) extends EventCC Now, the question is, how can I easily convert generic Events to the specific case classes. This is my first stab at it: def event2CC[T <: EventCC](event: Event): T = event.getVerb match { case "login" => Login(event.getSubject, event.getTimestamp) case "follow" => Follow( event.getSubject, event.getDirectObject.getOrElse(0), event.getTimestamp ) // ... } Unfortunately, this is wrong. <console>:11: error: type mismatch; found : Login required: T case "login" => Login(event.getSubject, event.getTimestamp) ^ <console>:12: error: type mismatch; found : Follow required: T case "follow" => Follow(event.getSubject, event.getDirectObject.getOrElse(0), event.getTimestamp) Could someone with greater type-fu than me explain if, 1) if what I want to do is possible (or reasonable, for that matter), and 2) if so, how to fix event2CC. Thanks!

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  • Unable to access Java-created file -- sometimes

    - by BlairHippo
    In Java, I'm working with code running under WinXP that creates a file like this: public synchronized void store(Properties props, byte[] data) { try { File file = filenameBasedOnProperties(props); if ( file.exists() ) { return; } File temp = File.createTempFile("tempfile", null); FileOutputStream out = new FileOutputStream(temp); out.write(data); out.flush(); out.close(); file.getParentFile().mkdirs(); temp.renameTo(file); } catch (IOException ex) { // Complain and whine and stuff } } Sometimes, when a file is created this way, it's just about totally inaccessible from outside the code (though the code responsible for opening and reading the file has no problem), even when the application isn't running. When accessed via Windows Explorer, I can't move, rename, delete, or even open the file. Under Cygwin, I get the following when I ls -l the directory: ls: cannot access [big-honkin-filename] total 0 ?????????? ? ? ? ? ? [big-honkin-filename] As implied, the filenames are big, but under the 260-character max for XP (though they are slightly over 200 characters). To further add to the sense the my computer just wants me to feel stupid, sometimes the files created by this code are perfectly normal. The only pattern I've spotted is that once one file in the directory "locks", the rest are screwed. Anybody ever run into something like this before, or have any insights into what's going on here?

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  • Entity Framework and differences between Contains between SQL and objects using ToLower

    - by John Ptacek
    I have run into an "issue" I am not quite sure I understand with Entity Framework. I am using Entity Framework 4 and have tried to utilize a TDD approach. As a result, I recently implemented a search feature using a Repository pattern. For my test project, I am implementing my repository interface and have a set of "fake" object data I am using for test purposes. I ran into an issue trying to get the Contains clause to work for case invariant search. My code snippet for both my test and the repository class used against the database is as follows: if (!string.IsNullOrEmpty(Description)) { items = items.Where(r => r.Description.ToLower().Contains(Description.ToLower())); } However, when I ran my test cases the results where not populated if my case did not match the underlying data. I tried looking into what I thought was an issue for a while. To clear my mind, I went for a run and wondered if the same code with EF would work against a SQL back end database, since SQL will explicitly support the like command and it executed as I expected, using the same logic. I understand why EF against the database back end supports the Contains clause. However, I was surprised that my unit tests did not. Any ideas why other than the SQL server support of the like clause when I use objects I populate in a collection instead of against the database server? Thanks! John

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  • JSF Float Conversion

    - by Phill Sacre
    I'm using JSF 1.2 with IceFaces 1.8 in a project here. I have a page which is basically a big edit grid for a whole bunch of floating-point number fields. This is implemented with inputText fields on the page pointing at a value object with primitive float types Now, as a new requirement sees some of the fields be nullable, I wanted to change the value object to use Float objects rather than primitive types. I didn't think I'd need to do anything to the page to accomodate this. However, when I make the change I get the following error: /pages/page.xhtml @79,14 value="#{row.targetValue}": java.lang.IllegalArgumentException: argument type mismatch And /pages/page.xhtml @79,14 value="#{row.targetValue}": java.lang.IllegalArgumentException: java.lang.ClassCastException@1449aa1 The page looks like this: <ice:inputText value="#{row.targetValue}" size="4"> <f:convertNumber pattern="###.#" /> </ice:inputText> I've also tried adding in <f:convert convertId="javax.faces.Float" /> in there as well but that doesn't seem to work either! Neither does changing the value object types to Double. I'm sure I'm probably missing something really simple but I've been staring at this for a while now and no answers are immediately obvious!

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  • Using git filter-branch to remove commits by their commit message

    - by machineghost
    In our repository we have a convention where every commit message starts with a certain pattern: Redmine #555: SOME_MESSAGE We also do a bit of rebasing to bring in the potential release branch's changes to a specific issue's branch. In other words, I might have branch "foo-555", but before I merge it in to branch "pre-release" I need to get any commits that pre-release has that foo-555 doesn't (so that foo-555 can fast-forward merge in to pre-release). However, because pre-release sometimes changes, we sometimes wind up with situations where you bring in a commit from pre-release, but then that commit later gets removed from pre-release. It's easy to identify commits that came from pre-release, because the number from their commit message won't match the branch number; for instance, if I see "Redmine #123: ..." in my foo-555 branch, I know that its not a commit from my branch. So now the question: I'd like to remove all of the commits that "don't belong" to a branch; in other words, any commit that: Is in my foo-555 branch, but not in the pre-release branch (pre-release..foo-555) Has a commit message that doesn't start with "Redmine #555" but of course "555" will vary from branch to branch. Is there any way to use filter-branch (or any other tool) to accomplish this? Currently the only way I can see to do it is to do go an interactive rebase ("git rebase -i") and manually remove all the "bad" commits.

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  • Database and logic layer for ASP.NET MVC application

    - by Ismail
    I'm going to start a new project which is going to be small initially but may grow to big over the years. I'm strongly convinced that I'm going to use ASP.NET MVC with jQuery for UI. I want to go for MySQL as database for some reasons but worried on few things. I've a good years of experience working on SQL Server databases and on one project I've had a bad experience creating and managing stored procedures on MySQL database. I'm totally new to Linq but I see that it is easier to use once you are familiar with it. First thing is that accessing data should be easy. So I thought I should use MySQL to Linq but somewhere I read that it is not directly supported but MySQL .NET connector adds support for EntityFramework. I don't know what are the pros and cons of it. I would love if I can implement repository pattern as it allows to apply filter in logic layer rather than in data access layer. Will it be possible if I use Entity Framework? I'm not clear on how I should go about all this or I should just forget every thing and directly use SQL to Linq on SQL Server. I'm also concerned about the performance. Someone told me that if we use Entity framework it fetches lot of data and then filter it. Is that right? So questions basically are - Is MySQL to Linq possible? If yes where can I get more details on it? Pros and cons of using EntityFramework with MySQL? Will it be easy to access data using EntityFramework with MySQL? Will I be able to implement repository patter which allows applying filter in logic layer rather than data access layer (when I use EntityFramework with MySQL) Does it fetches hell lot of data from database and then apply filter on it? If it sounds too many questions from my side in that case, if you can just let me know what you will do (with a considerable reason) in this situation as an experienced person in this area, that should answer my question.

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  • How to allow one thread to mutate an array property while another thread iterates on a copy of the a

    - by Steve918
    I would like to implement an observer pattern in Objective-C where the observer implements an interface similar to SKPaymentTransactionObserver and the observable class just extends my base observable. My observable class looks something like what is below. Notice I'm making copies of the observers before enumeration to avoid throwing an exception . I've tried adding an NSLock around add observers and notify observers, but I run into a deadlock. What would be the proper way to handle concurrency when observers are being added as notifications are being sent? @implementation Observable -(void)notifyObservers:(SEL)selector { @synchronized(self) { NSSet* observer_copy = [observers copy]; for (id observer in observer_copy) { if([observer respondsToSelector: selector]) { [observer performSelector: selector]; } } [observer_copy release]; } } -(void)notifyObservers:(SEL)selector withObject:(id)arg1 withObject:(id)arg2 { @synchronized(self) { NSSet* observer_copy = [observers copy]; for (id observer in observer_copy) { if([observer respondsToSelector: selector]) { [observer performSelector: selector withObject: arg1 withObject: arg2]; } } [observer_copy release]; } } -(void)addObserver:(id)observer { @synchronized(self) { [observers addObject: observer]; } } -(void)removeObserver:(id)observer { @synchronized(self) { [observers removeObject: observer]; } }

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  • How does real world login process happen in web application in Java?

    - by Nitesh Panchal
    Hello, I am very much confused regarding login process that happen in Java web application. I read many tutorials regarding jdbcRealm and JAAS. But, one thing that i don't understand is that why should i use them ? Can't i simply check directly against my database of users? and once they successfully login to the site, i store some variable in session as a flag. And probably check that session variable on all restricted pages (I mean keep a filter for restricted resources url pattern).If the flag doesn't exist simply redirect the user to login page. Is this approach correct?Does this approch sound correct? If yes, then why did all this JAAS and jdbcRealm came into existence? Secondly, I am trying to completely implement SAS(Software as service) in my web application, meaning everything is done through web services.If i use webservices, is it possible to use jdbcRealm? If not, then is it possible to use JAAS? If yes, then please show me some example which uses mySql as a database and then authenticates and authorizes. I even heard about Spring Security. But, i am confused about that too in the sense that how do i use webservice with Spring Security. Please help me. I am really very confused. I read sun's tutorials but they only keep talking about theories. For programmers to understand a simple concept, they show a 100 page theory first before they finally come to one example.

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  • Should a new language compiler target the JVM?

    - by Pindatjuh
    I'm developing a new language. My initial target was to compile to native x86 for the Windows platform, but now I am in doubt. I've seen some new languages target the JVM (most notable Scala and Clojure). Ofcourse it's not possible to port every language easily to the JVM; to do so, it may lead to small changes to the language and it's design. So that's the reason behind this doubt, and thus this question: Is targetting the JVM a good idea, when creating a compiler for a new language? Or should I stick with x86? I have experience in generating JVM bytecode. Are there any workarounds to JVM's GC? The language has deterministic implicit memory management. How to produce JIT-compatible bytecode, such that it will get the highest speedup? Is it similar to compiling for IA-32, such as the 4-1-1 muops pattern on Pentium? I can imagine some advantages (please correct me if I'm wrong): JVM bytecode is easier than x86. Like x86 communicates with Windows, JVM communicates with the Java Foundation Classes. To provide I/O, Threading, GUI, etc. Implementing "lightweight"-threads.I've seen a very clever implementation of this at http://www.malhar.net/sriram/kilim/. Most advantages of the Java Runtime (portability, etc.) The disadvantages, as I imagined, are: Less freedom? On x86 it'll be more easy to create low-level constructs, while JVM has a higher level (more abstract) processor. Most disadvantages of the Java Runtime (no native dynamic typing, etc.)

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  • Adding exclusive filter for <static initializer> in findbugs

    - by MilanAleksic
    Hi all, I want my findbugs report not show the following error: DM_NUMBER_CTOR: Method invokes inefficient Number constructor; use static valueOf instead The problem is that this happens in groovy-generated code files, so I can't control the source code - that is why I want to exclude it and add it to my exclude filter. I do not want to add explicitly class (since I make API that many tools will use, I want my filter to be generic). I would not like to completely remove this bug from the report by type, I would really like to only exclude this bug from appearing if it happenned in "static initializer" methods. Any idea? I tried the filter below but no luck, maybe somebody has better idea? <Match> <Method name="~.*static initializer.*" /> <Bug pattern="DM_NUMBER_CTOR" /> </Match> Here is the "stacktrace" of FindBugs in that case: In class net.milanaleksic.cuc.tools.sound.SoundPlayerTool In method net.milanaleksic.cuc.tools.sound.SoundPlayerTool.() Called method new Long(long) Should call Long.valueOf(long) instead In SoundPlayerTool.groovy

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  • Processing command-line arguments in prefix notation in Python

    - by ejm
    I'm trying to parse a command-line in Python which looks like the following: $ ./command -o option1 arg1 -o option2 arg2 arg3 In other words, the command takes an unlimited number of arguments, and each argument may optionally be preceded with an -o option, which relates specifically to that argument. I think this is called a "prefix notation". In the Bourne shell I would do something like the following: while test -n "$1" do if test "$1" = '-o' then option="$2" shift 2 fi # Work with $1 (the argument) and $option (the option) # ... shift done Looking around at the Bash tutorials, etc. this seems to be the accepted idiom, so I'm guessing Bash is optimized to work with command-line arguments this way. Trying to implement this pattern in Python, my first guess was to use pop(), as this is basically a stack operation. But I'm guessing this won't work as well on Python because the list of arguments in sys.argv is in the wrong order and would have to be processed like a queue (i.e. pop from the left). I've read that lists are not optimized for use as queues in Python. So, my ideas are: convert argv to a collections.deque and use popleft(), reverse argv using reverse() and use pop(), or maybe just work with the int list indices themselves. Does anyone know of a better way to do this, otherwise which of my ideas would be best-practise in Python?

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  • Should frontend and backend handled by different controllers?

    - by DR
    In my previous learning projects I always used a single controller, but know I wonder if that is good practice or even always possible. In all RESTful Rails tutorials the controllers have a show, an edit and an index view. If an authorized user is logged on, the edit view becomes available and the index view shows additional data manipulation controls, like a delete button or a link to the edit view. Now I have a Rails application which falls exactly into this pattern, but the index view is not reusable: The normal user sees a flashy index page with lots of pictures, complex layout, no Javascript requirement, ... The Admin user index has a completly different minimalistic design, jQuery table and lots of additional data, ... Now I'm not sure how to handle this case. I can think of the following: Single controller, single view: The view is split into two large blocks/partials using an if statement. Single controller, two views: index and index_admin. Two different controllers: BookController and BookAdminController None of this solutions seems perfect, but for now I'm inclined to use the 3rd option. What's the preferred way to do this?

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  • Null Safe dereferencing in Java like ?. in Groovy using Maybe monad

    - by Sathish
    I'm working on a codebase ported from Objective C to Java. There are several usages of method chaining without nullchecks dog.collar().tag().name() I was looking for something similar to safe-dereferencing operator ?. in Groovy instead of having nullchecks dog.collar?.tag?.name This led to Maybe monad to have the notion of Nothing instead of Null. But all the implementations of Nothing i came across throw exception when value is accessed which still doesn't solve the chaining problem. I made Nothing return a mock, which behaves like NullObject pattern. But it solves the chaining problem. Is there anything wrong with this implementation of Nothing? [http://github.com/sathish316/jsafederef/blob/master/src/s2k/util/safederef/Nothing.java] As far as i can see 1. It feels odd to use mocking library in code 2. It doesn't stop at the first null. 3. How do i distinguish between null result because of null reference or name actually being null? How is it distinguished in Groovy code?

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  • php parsing speed optimization

    - by Arnaud
    I would like to add tooltip or generate link according to the element available in the database, for exemple if the html page printed is: to reboot your linux host in single-user mode you can ... I will use explode(" ", $row[page]) and the idea is now to lookup for every single word in the page to find out if they have a related referance in this exemple let's say i've got a table referance an one entry for reboot and one for linux reboot: restart a computeur linux: operating system now my output will look like (replaced < and by @) to @a href="ref/reboot"@reboot@/a@ your @a href="ref/linux"@linux@/a@ host in single-user mode you can ... Instead of have a static list generated when I saved the content, if I add more keyword in the future, then the text will become more interactive. My main concerne and question is how can I create a efficient enough process to do it ? Should I store all the db entry in an array and compare them ? Do an sql query for each word (seems to be crazy) Dump the table in a file and use a very long regex or a "grep -f pattern data" way of doing it? Or or or or I'm sure it must be a better way of doing it, just don't have a clue about it, or maybe this will be far too resource un-friendly and I should avoid doing such things. Cheers!

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  • Injecting Dependencies into Domain Model classes with Nhibernate (ASP.NET MVC + IOC)

    - by Sunday Ironfoot
    I'm building an ASP.NET MVC application that uses a DDD (Domain Driven Design) approach with database access handled by NHibernate. I have domain model class (Administrator) that I want to inject a dependency into via an IOC Container such as Castle Windsor, something like this: public class Administrator { public virtual int Id { get; set; } //.. snip ..// public virtual string HashedPassword { get; protected set; } public void SetPassword(string plainTextPassword) { IHashingService hasher = IocContainer.Resolve<IHashingService>(); this.HashedPassword = hasher.Hash(plainTextPassword); } } I basically want to inject IHashingService for the SetPassword method without calling the IOC Container directly (because this is suppose to be an IOC Anti-pattern). But I'm not sure how to go about doing it. My Administrator object either gets instantiated via new Administrator(); or it gets loaded via NHibernate, so how would I inject the IHashingService into the Administrator class? On second thoughts, am I going about this the right way? I was hoping to avoid having my codebase littered with... currentAdmin.Password = HashUtils.Hash(password, Algorithm.Sha512); ...and instead get the domain model itself to take care of hashing and neatly encapsulate it away. I can envisage another developer accidently choosing the wrong algorithm and having some passwords as Sha512, and some as MD5, some with one salt, and some with a different salt etc. etc. Instead if developers are writing... currentAdmin.SetPassword(password); ...then that would hide those details away and take care of those problems listed above would it not?

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  • How do I convert an AMD module from a singleton to an instance?

    - by Jamie Ide
    I'm trying to convert a working Durandal view model module from a singleton to an instance. The original working version followed this pattern: define(['knockout'], function(ko) { var vm = { activate: activate, companyId: null; company: ko.observable({}) }; return vm; function activate(companyId) { vm.companyId = companyId; //get company data then vm.company(data); } } The new version exports a function so that I get a new instance on every request... define(['knockout'], function(ko) { var vm = function() { activate = activate; companyId = null; company = ko.observable({}); }; return vm; function activate(companyId) { vm.companyId = companyId; //get company data then vm.company(data); } } The error I'm getting is "object function () [...function signature...] has no method company on the line vm.company(data);. What am I doing wrong? Why can I set the property but can't access the knockout observable? How should I refactor the original code so that I get a new instance on every request? My efforts to simplify the code for this question hid the actual problem. My real code was using Q promises and calling two methods with Q.All. Since Q is in the global namespace, it couldn't resolve my viewmodel after converting to a function. Passing the view model to the methods called by Q resolved the problem.

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  • How to represent and insert into an ordered list in SQL?

    - by Travis
    I want to represent the list "hi", "hello", "goodbye", "good day", "howdy" (with that order), in a SQL table: pk | i | val ------------ 1 | 0 | hi 0 | 2 | hello 2 | 3 | goodbye 3 | 4 | good day 5 | 6 | howdy 'pk' is the primary key column. Disregard its values. 'i' is the "index" that defines that order of the values in the 'val' column. It is only used to establish the order and the values are otherwise unimportant. The problem I'm having is with inserting values into the list while maintaining the order. For example, if I want to insert "hey" and I want it to appear between "hello" and "goodbye", then I have to shift the 'i' values of "goodbye" and "good day" (but preferably not "howdy") to make room for the new entry. So, is there a standard SQL pattern to do the shift operation, but only shift the elements that are necessary? (Note that a simple "UPDATE table SET i=i+1 WHERE i=3" doesn't work, because it violates the uniqueness constraint on 'i', and also it updates the "howdy" row unnecessarily.) Or, is there a better way to represent the ordered list? I suppose you could make 'i' a floating point value and choose values between, but then you have to have a separate rebalancing operation when no such value exists. Or, is there some standard algorithm for generating string values between arbitrary other strings, if I were to make 'i' a varchar? Or should I just represent it as a linked list? I was avoiding that because I'd like to also be able to do a SELECT .. ORDER BY to get all the elements in order.

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