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Sed: regular expression match lines without /' web.xml Takes: <a>  <b> bla </b> </a> Produces:   --> // NOTE: there are two end comments.     Ideally I would like to not use my sed script to comment things that are already commented. Ie:       I could do something like this: sed 's/^\([ \t]*\)\(.*[0-9a-zA-Z<].*\)$/\1/' web.xml sed 's/^[ \t]*\) -->/\1/' web.xml but I think a one liner is cleaner (?) This is pretty similar: http://stackoverflow.com/questions/436850/matching-a-line-that-doesnt-contain-specific-text-with-regular-expressions

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How to conduct an interview for a development position remotely?

- by sharptooth

Usually we run interviews in office. We have a room with a table, the interviewee and one or two interviewers sit at the table, interviewers ask questions, often accompanied with code snippets on paper, the interviewee (hopefully) answers them, writes code snippets to illustrate his point. Usually it's something like an interviewer writes about five lines of C++ code and asks some specific question - quite a little code. Now we need to do the same remotely. We will be in our office and the interviewee will be far away - we are asked to help hire a person for another office located abroad. Of course we can use some technology for voice calls, but I'm afraid it's the most we can count on. I see a whole set of obstacles here: how to write illustration code snippets and exchange them efficiently? what to do to compensate for the fact that we're not native English speakers and the interviewees might or might be not native English speakers (I'm afraid this can make conversation significantly harder)? Are there any best practices for this situation? How could we address the obstacles listed? What other things should we consider to run the interview most efficiently?

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how to pass vector of string to foo(char const *const *const)?

- by user347208

Hi, This is my first post so please be nice. I searched in this forum and googled but I still can not find the answer. This problem has bothered me for more than a day, so please give me some help. Thank you. I need to pass a vector of string to a library function foo(char const *const *const). I can not pass the &Vec[0] since it's a pointer to a string. Therefore, I have an array and pass the c_str() to that array. The following is my code (aNames is the vector of string): const char* aR[aNames.size()]; std::transform(aNames.begin(), aNames.end(), aR, boost::bind(&std::string::c_str, _1)); foo(aR); However, it seems it causes some undefined behavior: If I run the above code, then the function foo throw some warnings about illegal characters ('èI' blablabla) in aR. If I print aR before function foo like this: std::copy(aR, aR+rowNames.size(), std::ostream_iterator<const char*>(std::cout, "\n")); foo(aR); Then, everything is fine. My questions are: Does the conversion causes undefined behavior? If so, why? What is the correct way to pass vector of string to foo(char const *const *const)? Thank you very much for your help!

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Is this an error in "More Effective C++" in Item28?

- by particle128

I encountered a question when I was reading the item28 in More Effective C++ .In this item, the author shows to us that we can use member template in SmartPtr such that the SmartPtr<Cassette> can be converted to SmartPtr<MusicProduct>. The following code is not the same as in the book,but has the same effect. #include <iostream> class Base{}; class Derived:public Base{}; template<typename T> class smart{ public: smart(T* ptr):ptr(ptr){} template<typename U> operator smart<U>() { return smart<U>(ptr); } ~smart(){delete ptr;} private: T* ptr; }; void test(const smart<Base>& ) {} int main() { smart<Derived> sd(new Derived); test(sd); return 0; } It indeed can be compiled without compilation error. But when I ran the executable file, I got a core dump. I think that's because the member function of the conversion operator makes a temporary smart, which has a pointer to the same ptr in sd (its type is smart<Derived>). So the delete directive operates twice. What's more, after calling test, we can never use sd any more, since ptr in sd has already been delete. Now my questions are : Is my thought right? Or my code is not the same as the original code in the book? If my thought is right, is there any method to do this? Thanks very much for your help.

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implementing user tracking (logging) in Rails 3

- by seth.vargo

Hi, I'm creating a Rails application in which logging individual user actions is vital. Every time a user clicks a url, I want to log the action along with all parameters. Here is my current implementation: class CreateActivityLogs < ActiveRecord::Migration create_table :activity_logs do |t| t.references :user t.string :ip_address t.string :referring_url t.string :current_url t.text :params t.text :action t.timestamps end end class ActivityLog < ActiveRecord::Base belongs_to :user end In a controller, I'd like to be able to do something like the following: ... ActivityLog::log @user.id, params, 'did foo with bar' ... I'd like to have the ActivityLog::log method automatically get the IP address, referring url, and current url (I know how to do this already) and create a new record in the table. So, my questions are: How do I do this? How do I use ActivityLog without having to create an instance everytime I want to log? Is this the best way? Some people have argued for a flat-file log for this kind of logging - however, I want admins to be able to see a user's activity in the backend as well, so I thought a database solution may be better?

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PHP rewrite an included file - is this a valid script?

- by Poni

Hi all! I've made this question: http://stackoverflow.com/questions/2921469/php-mutual-exclusion-mutex As said there, I want several sources to send their stats once in a while, and these stats will be showed at the website's main page. My problem is that I want this to be done in an atomic manner, so no update of the stats will overlap another one running in the background. Now, I came up with this solution and I want you PHP experts to judge it. stats.php <?php define("my_counter", 12); ?> index.php <?php include "stats.php"; echo constant("my_counter"); ?> update.php <?php $old_error_reporting = error_reporting(0); include "stats.php"; define("my_stats_template",' <?php define("my_counter", %d); ?> '); $fd = fopen("stats.php", "w+"); if($fd) { if (flock($fd, LOCK_EX)) { $my_counter = 0; try { $my_counter = constant("my_counter"); } catch(Exception $e) { } $my_counter++; $new_stats = sprintf(constant("my_stats_template"), $my_counter); echo "Counter should stand at $my_counter"; fwrite($fd, $new_stats); } flock($fd, LOCK_UN); fclose($fd); } error_reporting($old_error_reporting); ?> Several clients will call the "update.php" file once every 60sec each. The "index.php" is going to use the "stats.php" file all the time as you can see. What's your opinion?

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Can I use a UINavigationController as the detail view of a UISplitViewController?

- by B Sweigard

I'm running into a problem with an iPad app where I would like to have UINavigationControllers in both of the views within a UISplitView. I've looked through other similar questions here, but most link to a tutorial online that doesn't completely solve the problem. Here's a 2-minute walkthrough to re-create the problem I'm having: Create a New Project in XCode, starting from the Split View-based Application template. Add the following NSLog statement as the first line within the DetailViewController's willHideViewController method: NSLog(@"toolbar: %@", toolbar); If you run the application now, the log will show that the DetailViewController's toolbar is alive and well. Now... Open MainWindow.xib and expand the SplitViewController. Drag a Navigation Controller from the library on top of the DetailViewController. Expand the new Navigation Controller and change the class of the UIViewController within to a DetailViewController. Ctrl-drag from the SplitViewController to the DetailViewController and assign it as the delegate. Save MainWindow.xib and run the app again. At this point, the detail view has a navigation bar and an empty toolbar. If you view the logs, you should find that the toolbar is null. Why is this? Am I missing some sort of connection in Interface Builder? Is the navigation bar the problem for some reason? Unlike the tutorial at http://www.cimgf.com/2010/05/24/fixing-the-uisplitviewcontroller-template/, I would like to keep both the navigation bar and the toolbar (preferably with the toolbar at the top when in portrait and not visible when in landscape), so that I still have a functional "Back" button when the iPad is in portrait orientation. Does anyone have any suggestions for fixing this problem? An example project with this sort of set-up would be ideal.

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How do I conditionally compile C code snippets to my Perl module?

- by mobrule

I have a module that will target several different operating systems and configurations. Sometimes, some C code can make this module's task a little easier, so I have some C functions that I would like to bind the code. I don't have to bind the C functions -- I can't guarantee that the end-user even has a C compiler, for instance, and it's generally not a problem to failover gracefully to a pure Perl way of accomplishing the same thing -- but it would be nice if I could call the C functions from the Perl script. Still with me? Here's another tricky part. Just about all of the C code is system specific -- a function written for Windows won't compile on Linux and vice-versa, and the function that does a similar thing on Solaris will look totally different. #include <some/Windows/headerfile.h> int foo_for_Windows_c(int a,double b) { do_windows_stuff(); return 42; } #include <path/to/linux/headerfile.h> int foo_for_linux_c(int a,double b) { do_linux_stuff(7); return 42; } Furthermore, even for native code that targets the same system, it's possible that only some of them can be compiled on any particular configuration. #include <some/headerfile/that/might/not/even/exist.h> int bar_for_solaris_c(int a,double b) { call_solaris_library_that_might_be_installed_here(11); return 19; } But ideally we could still use the C functions that would compile with that configuration. So my questions are: how can I compile C functions conditionally (compile only the code that is appropriate for the current value of $^O)? how can I compile C functions individually (some functions might not compile, but we still want to use the ones that can)? can I do this at build-time (while the end-user is installing the module) or at run-time (with Inline::C, for example)? Which way is better? how would I tell which functions were successfully compiled and are available for use from Perl? All thoughts appreciated!

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Processor, OS : 32bit, 64 bit

- by Sandbox

I am new to programming and come from a non-CS background (no formal degree). I mostly program winforms using C#. I am confused about 32 bit and 64 bit.... I mean, have heard about 32 bit OS, 32 bit processor and based on which a program can have maximum memory. How it affects the speed of a program. There are lot more questions which keep coming to mind. I tried to go through some Computer Organization and Architecture books. But, either I am too dumb to understand what is written in there or the writers assume that the reader has some CS background. Can someone explain me these things in a plain simple English or point me to something which does that. EDIT: I have read things like In 32-bit mode, they can access up to 4GB memory; in 64-bit mode, they can access much much more....I want to know WHY to all such things. BOUNTY: Answers below are really good....esp one by Martin. But, I am looking at a thorough explanation, but in plain simple English.

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What is causing this template-related compile error? (c++)

- by Setien

When I try to compile this: #include <map> #include <string> template <class T> class ZUniquePool { typedef std::map< int, T* > ZObjectMap; ZObjectMap m_objects; public: T * Get( int id ) { ZObjectMap::const_iterator it = m_objects.find( id ); if( it == m_objects.end() ) { T * p = new T; m_objects[ id ] = p; return p; } return m_objects[ id ]; } }; int main( int argc, char * args ) { ZUniquePool< std::string > pool; return 0; } I get this: main.cpp: In member function ‘T* ZUniquePool<T>::Get(int)’: main.cpp:12: error: expected `;' before ‘it’ main.cpp:13: error: ‘it’ was not declared in this scope I'm using GCC 4.2.1 on Mac OS X. It works in VS2008. I'm wondering whether it might be a variation of this problem: http://stackoverflow.com/questions/1364837/why-doesnt-this-c-template-code-compile But as my error output is only partially similar, and my code works in VS2008, I am not sure. Can anyone shed some light on what I am doing wrong?

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Coloring Default Buttons - color filter only on unfocused state

- by rlo

I want to buttons of different colors, but I want to do so while using the default button background resource in order to preserve the onfocus and onclick states. This is because I want to use the default highlight color of the OS for my app, which is NOT always orange (HTC Sense makes it green). I found that adding a color filter to the button's background drawable works great (in this case, blue): myButton.getBackground().setColorFilter(Color.parseColor(this.getString (R.color.button_blue)), Mode.MULTIPLY); BUT, when the button is focused or clicked, it turns a nasty orange_blue because it mixes the color filter with the orange of the background drawable. I want to ONLY set this color filter for the unfocused/unclicked nine- patch drawable within the default button's statelistdrawable. I'm not sure how else to do this. I see a similar solution here: http://stackoverflow.com/questions/2065430/fixed-android-detecting-fo... but I have some concerns with that solution, mainly what if the OS changes the graphic of the default button? Since the normal unfocused/ unpressed graphic is now hardcoded into the app, it would break the flow. Maybe can someone comment on whether it would be good or bad practice to hardcode the default graphic into the app? What are the chances of the OS completely changing the graphic? Any help please? Thanks very much!!

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Must JsUnit Cases Reside Under the Same Directory as JsUnit?

- by chernevik

I have installed JsUnit and a test case as follows: /home/chernevik/Programming/JavaScript/jsunit /home/chernevik/Programming/JavaScript/jsunit/testRunner.html /home/chernevik/Programming/JavaScript/jsunit/myTests/lineTestAbs.html /home/chernevik/Programming/JavaScript/lineTestAbs.html When I open the test runner in a browser as a file, and test lineTestAbs.html from the jsunit/myTests directory, it passes. When I test the same file from the JavaScript directory, the test runner times out, asking if the file exists or is a test page. Questions: Am I doing something wrong here, or is this the expected behavior? Is it possible to put test cases in a different directory structure, and if so what is the proper path reference to to JsUnitCore.js? Would JsUnit behave differently if the files were retrieved from an HTTP server? <html> <head> <title>Test Page line(m, x, b)</title> <script language="JavaScript" src="/home/chernevik/Programming/JavaScript/jsunit/app/jsUnitCore.js"></script> <script language="JavaScript"> function line(m, x, b) { return m*x + b; } function testCalculationIsValid() { assertEquals("zero intercept", 10, line(5, 2, 0)); assertEquals("zero slope", 5, line(0, 2, 5)); assertEquals("at x = 10", 25, line(2, 10, 5)); } </script> </head> <body> This pages tests line(m, x, b). </body> </html>

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I am trying to access the individual bytes in a floating point number and I am getting unexpected results

- by oweinh

So I have this so far: #include <iostream> #include <string> #include <typeinfo> using namespace std; int main () { float f = 3.45; // just an example fp# char* ptr = (char*)&f; // a character pointer to the first byte of the fp#? cout << int(ptr[0]) << endl; // these lines are just to see if I get what I cout << int(ptr[1]) << endl; // am looking for... I want ints that I can cout << int(ptr[2]) << endl; // otherwise manipulate. cout << int(ptr[3]) << endl; } the result is: -51 -52 92 64 so obviously -51 and -52 are not in the byte range that I would expect for a char... I have taken information from similar questions to arrive at this code and from all discussions, a conversion from char to int is straightforward. So why negative values? I am trying to look at a four-byte number, therefore I would expect 4 integers, each in the range 0-255. I am using Codeblocks 13.12 with gcc 4.8.1 with option -std=C++11 on a Windows 8.1 device.

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Would there be a market for this idea (cross platform VM for iPhone OS)

- by Tzury Bar Yochay

For a long time I wondered if the following idea worth a nickel or just a waste of time and energy. I am willing to start a project which will provide a kind of a VM for all iPxxx apps - so developed once for iPxxx can run on a Macbook, iMac, Linux, Android and windows (desktop and mobile). You get the idea, right? I want to do to the current iPhone SDK, the same as what Mono did to Microsoft .Net and perhaps a more complete set of implementation. I tend to believe that if overnight all apps on appstore become available on the android market as well that would be a mini revolution. Think about running iPad apps on every tablet that will come out to the market in the future. Wouldn't it be fantastic to all the developers, which from now on, can write once and sell everywhere? The main questions which I ask myself repeatedly is: "Is This Legal?" - I mean, say I have done this, would apple's lawyers will start sending me all kinds of nasty emails? I am willing to hear your opinion about this idea as well as if some of you willing and able to join forces and start this open source project.

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Why extremely occasionally will one of bof/eof be true for a new non-empty recordset

- by jjb

set recordsetname = databasename.openrecordset(SQLString) if recordsetname.bof <> true and recordsetname.eof <> true then 'do something end if 2 questions : the above test can evaluate to false incorrectly but only extremely rarely (I've had one lurking in my code and it failed today, I believe for the first time in 5 years of daily use-that's how I found it). Why very occasionally will one of bof/eof be true for a non-empty recordset. It seems so rare that I wonder why it occurs at all. Is this a foolproof replacement: if recordsetname.bof <> true or recordsetname.eof <> true then Edit to add details of code : Customers have orders, each order begins with a BeginOrder item and end with an EndOrder item and in between are the items in the order. The SQL is: ' ids are autoincrement long integers ' SQLString = "select * from Orders where type = OrderBegin or type = OrderEnd" Dim OrderOpen as Boolean OrderOpen = False Set rs = db.Openrecordset(SQLString) If rs.bof <> True And rs.eof <> True Then myrec.movelast If rs.fields("type").value = BeginOrder Then OrderOpen = True End If End If If OrderOpen F False Then 'code here to add new BeginOrder Item to Orders table ' End If ShowOrderHistory 'displays the customer's Order history ' In this case which looks this this BeginOrder Item a Item b ... Item n EndOrder BeginOrder Item a Item b ... Item n EndOrder BeginOrder Item a item b ... Item m BeginOrder <----should not be there as previous order still open

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Rails from with better url

- by Sam

wow, switching to rest is a different paradigm for sure and is mainly a headache right now. view <% form_tag (businesses_path, :method => "get") do %> <%= select_tag :business_category_id, options_for_select(@business_categories.collect {|bc| [bc.name, bc.id ]}.insert(0, ["All Containers", 0]), which_business_category(@business_category) ), { :onchange => "this.form.submit();"} %> <% end %> controller def index @business_categories = BusinessCategory.find(:all) if params[:business_category_id].to_i != 0 @business_category = BusinessCategory.find(params[:business_category_id]) @businesses = @business_category.businesses else @businesses = Business.all end respond_to do |format| format.html # index.html.erb format.xml { render :xml => @businesses } end end routes map.resources What I want to to is get a better url than what this form is presenting which is the following: http://localhost:3000/businesses?business_category_id=1 Without rest I would have do something like http://localhost:3000/business/view/bbq bbq as permalink or I would have done http://localhost:300/business_categories/view/bbq and get the business that are associated with the category but I don't really know the best way of doing this. So the two questions are what is the best logic of finding a business by its categories using the latter form and number two how to get that in a pretty url all through restful routes in rails.

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C function prototype: void f(). Is it recommended?

- by ycalleecharan

Hi, I'm learning C and I saw in a book that a function prototype has the form void f() and in the function declaration or in the calling function, the f function takes arguments. Thus In the function declaration we have something like void f(long double y[], long double A) and in the calling function is f(y, A). The function is doing operations on the array y i.e. when the function is called, some elements in the array y are changing. A is just a constant numerical value that doesn't change. I have two questions: If defining the function prototype at the top in the program as void f() a good practice? Or is it better to put it as void f(long double y[], long double A) as in the function declaration? The called function f is changing elements in the array y. Is void the right return type? The program is working fine as such with the void as described. Or should I change all my "voids" to "long double". I'm working with long double as I need as much precision as possible though on my machine both double and long double gives me 15 precision digits. Thanks a lot

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Disable a form and all contained elements until an ajax query completes (or another solution to prev

- by Max Williams

I have a search form with inputs and selects, and when any input/select is changed i run some js and then make an ajax query with jquery. I want to stop the user from making further changes to the form while the request is in progress, as at the moment they can initiate several remote searches at once, effectively causing a race between the different searches. It seems like the best solution to this is to prevent the user from interacting with the form while waiting for the request to come back. At the moment i'm doing this in the dumbest way possible by hiding the form before making the ajax query and then showing it again on success/error. This solves the problem but looks horrible and isn't really acceptable. Is there another, better way to prevent interaction with the form? To make things more complicated, to allow nice-looking selects, the user actually interacts with spans which have js hooked up to them to tie them to the actual, hidden, selects. So, even though the spans aren't inputs, they are contained in the form and represent the actual interactive elements of the form. Grateful for any advice - max. Here's what i'm doing now: function submitQuestionSearchForm(){ //bunch of irrelevant stuff var questionSearchForm = jQuery("#searchForm"); questionSearchForm.addClass("searching"); jQuery.ajax({ async: true, data: jQuery.param(questionSearchForm.serializeArray()), dataType: 'script', type: 'get', url: "/questions", success: function(msg){ //more irrelevant stuff questionSearchForm.removeClass("searching"); }, error: function(msg){ questionSearchForm.removeClass("searching"); } }); return true; }

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Square collision detection problem (iPhone).

- by thyrgle

Hi, I know I've probably posted three questions related to this then deleted them, but thats only because I solved them before I got an answer. But, this one I can not solve and I don't believe it is that hard compared to the others. So, with out further ado, here is my problem: So I am using Cocos2d and one of the major problem is they don't have buttons. To compensate for there lack in buttons I am trying to detect if when a touch ended did it collide with a square (the button). Here is my code: - (void)ccTouchesEnded:(NSSet*)touches withEvent:(UIEvent*)event { UITouch *touch = [touches anyObject]; CGPoint location = [touch locationInView:touch.view]; NSLog(@"%f", 240-location.y); if (isReady == YES) { if (((240-location.y) <= (240-StartButton.position.x - 100) || -(240-location.y) >= (240-StartButton.position.x) + 100) && ((160-location.x) <= (160-StartButton.position.y) - 25 || (160-location.x) >= (160-StartButton.position.y) + 25)) { NSLog(@"Coll:%f", 240-StartButton.position.x); CCScene *scene = [PlayScene node]; [[CCDirector sharedDirector] replaceScene:[CCZoomFlipAngularTransition transitionWithDuration:2.0f scene:scene orientation:kOrientationRightOver]]; } } } Do you know what I am doing wrong?

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I have data about deadlocks, but I can't understand why they occur (MS SQL/ASP.NET MVC)

- by Alex

I am receiving a lot of deadlocks in my big web application. http://stackoverflow.com/questions/2941233/how-to-automatically-re-run-deadlocked-transaction-asp-net-mvc-sql-server Here I wanted to re-run deadlocked transactions, but I was told to get rid of the deadlocks - it's much better, than trying to catch the deadlocks. So I spent the whole day with SQL profiler, setting the tracing keys etc. And this is what I got. There's a Users table. I have a very high usable page with the following query (it's not the only query, but it's the one that causes troubles) UPDATE Users SET views = views + 1 WHERE ID IN (SELECT AuthorID FROM Articles WHERE ArticleID = @ArticleID) And then there's the following query in ALL pages: User = DB.Users.SingleOrDefault(u => u.Password == password && u.Name == username); That's where I get User from cookies. Very often a deadlock occurs and this second LINQ TO SQL query is chosen as a victim, so it's not run, and users of my site see an error screen. I read a lot about deadlocks... And I don't understand why this is causing a deadlock. So obviously both of this queries run very often. At least once a second. Maybe even more often (300-400 users online). So they can be run at the same time very easily, but why does it cause a deadlock? Please help. Thank you

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Clarification of a some code

- by Legend

I have come across a website that appears to use Ajax but does not include any js file except one file called ajax.js which has the following: function run(c, f, b, a, d) { var e = null; if (b && f) { document.getElementById(b).innerHTML = f } if (window.XMLHttpRequest) { e = new XMLHttpRequest() } else { if (window.ActiveXObject) { e = new ActiveXObject(Microsoft.XMLHTTP) } } e.onreadystatechange = function () { if (e.readyState == 4) { if (e.status == 200 || e.statusText == "OK") { if (b) { document.getElementById(b).innerHTML = e.responseText } if (a) { setTimeout(a, 0) } } else { console.log("AJAX Error: " + e.status + " | " + e.statusText); if (b && d != 1) { document.getElementById(b).innerHTML = "AJAX Error. Please try refreshing." } } } }; e.open("GET", c, true); e.setRequestHeader("Content-Type", "application/x-www-form-urlencoded"); e.send(null) } Like you might have guessed, the way it issues queries inside the page with queries like this: run('page.php',loadingText,'ajax-test', 'LoadSamples()'); I must admit that this is the first time I've seen a page from which I could not figure how things are being done. I have a few questions: Is this Server-Side Ajax or something similar? If not, can someone clarify what exactly is this? Why does one use this? Is it for hiding the design details? (which are otherwise revealed in plain text by javascript) How difficult would it be to convert my existing application into this design pattern? (maybe a subjective question but any short suggestion will do) Any suggestions?

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how to set custom tab in jquery ui and use with rails

- by Katyal

I'm using jqueryUI for tabs on a page. I initialize it like below: $("#tabs").tabs(); <div id="tabs"> <ul> <li><a href="#tabs-4">Part A</a></li> <li><a href="#tabs-2">Part B</a></li> <li><a href="#tabs-5">Part C</a></li> </ul> <div id="tabs-4"> ..... </div> <div id="tabs-2"> .... </div> <div id="tabs-5"> .... </div> </div> I have 2 questions. How do I set the tab to be custom. say I want second tab to be shown first. $('#tabs').tabs(2) does not work. i got that from this link Let say I click on a button inside tab1. Clicking on the button takes control back to an action and then control comes back to this page. When the control comes back...then is it possible to set a custom tab?. For example. in tab 1 I click something...go back to the action...and then I want to come back to tab 2.

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Why should I prefer OSGi Services over exported packages?

- by Jens

Hi, I am trying to get my head around OSGi Services. The main question I keep asking myself is: What's the benefit of using services instead of working with bundles and their exported packages? As far as I know it seems the concept of Late Binding has something to do with it. Bundle dependencies are wired together at bundle start, so they are pretty fixed I guess. But with services it seems to be almost the same. A bundle starts and registers services or binds to services. Of course services can come and go whenever they want and you have to keep track of these chances. But the core idea doesn't seem that different to me. Another aspect to this seems to be that services are more flexible. There could be many implementations for one specific Interface. On the other hand there can be a lot of different implementations for a specific exported package too. In another text I read that the disadvantage of using exported packages is that they make the application more fragile than services. The author wrote that if you remove one bundle from the dependency graph other dependencies would no longer be met, thus possibly causing a domino effect on the whole graph. But couldn't the same happen if a service would go offline? To me it looks like service dependencies are no better than bundle dependencies. So far I could not find a blog post, book or presentation that could clearly describe why services are better than just exposing functionality by exporting and importing packages. To sum my questions up: What are the key benefits of using OSGi Services that make them superior to exporting and importing packages?

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How can I use two or more COUNT()s in one SELECT statament?

- by jjj

i develop this code: SELECT COUNT(NewEmployee.EmployeeID), NewEmployee.EmployeeId,EmployeeName FROM NewEmployee INNER JOIN NewTimeAttendance ON NewEmployee.EmployeeID = NewTimeAttendance.EmployeeID and NewTimeAttendance.TotalTime is null and (NewTimeAttendance.note = '' or NewTimeAttendance.note is null) and (month = 1 or month = 2 or month = 3) GROUP BY NewEmployee.EmployeeID, EmployeeName order by EmployeeID from my previous two questions selecting null stuff and counting issue...that amazing code is working beautifully fine..but now i need to select more than one count... ...searched (google) .... found alias...tried: SELECT COUNT(NewEmployee.EmployeeID) as attenddays, COUNT(NewEmployee.EmployeeID) as empabsent , NewEmployee.EmployeeId,EmployeeName FROM NewEmployee INNER JOIN NewTimeAttendance ON empabsent =NewEmployee.EmployeeID = NewTimeAttendance.EmployeeID and NewTimeAttendance.TotalTime is null and (NewTimeAttendance.note = '' or NewTimeAttendance.note is null ) and (month=1 or month =2 or month = 3) , attenddays = NewTimeAttendance.EmployeeID and NewTimeAttendance.TotalTime is null and (NewTimeAttendance.note = '' or NewTimeAttendance.note is null ) and (month=1 or month =2 or month = 3) GROUP BY NewEmployee.EmployeeID, EmployeeName order by EmployeeID Incorrect syntax near '='. second try: SELECT COUNT(NewEmployee.EmployeeID) as attenddays, COUNT(NewEmployee.EmployeeID) as absentdays, NewEmployee.EmployeeId,EmployeeName FROM NewEmployee INNER JOIN NewTimeAttendance ON attenddays(NewEmployee.EmployeeID = NewTimeAttendance.EmployeeID and NewTimeAttendance.TotalTime is null and (NewTimeAttendance.note = '' or NewTimeAttendance.note is null ) and (month=1 or month =2 or month = 3)) , absentdays(NewEmployee.EmployeeID = NewTimeAttendance.EmployeeID and NewTimeAttendance.TotalTime is null and (NewTimeAttendance.note = '' or NewTimeAttendance.note is null ) and (month=1 or month =2 or month = 3)) GROUP BY NewEmployee.EmployeeID, EmployeeName order by EmployeeID Incorrect syntax near '='. not very good ideas... so ...help thanks in advance

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PHP - Pull out array keys that have matching values?

- by MAZUMA

Is there a way to look inside an array and pull out the keys that have keys with matching values? Questions like this have been asked, but I'm not finding anything conclusive. So if my array looks like this Array ( [0] => Array ( [title] => Title 1 [type] => [message] => ) [1] => Array ( [title] => Title 2 [type] => [message] => ) [2] => Array ( [title] => Title 3 [type] => [message] => ) [3] => Array ( [title] => Title 2 [type] => Limited [message] => 39 ) [4] => Array ( [title] => Title 4 [type] => Offline [message] => 41 ) [5] => Array ( [title] => Title 5 [type] => [message] => ) And I want to get this Array ( [1] => Array ( [title] => Title 2 [type] => [message] => ) [3] => Array ( [title] => Title 2 [type] => Limited [message] => 39 ) )

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