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  • Building asynchronous cache pattern with JSP

    - by merweirdo
    I have a JSP that will take some 8 minutes to render. The code logic itself can not be made more efficient (it will update often and be updated by basically a pointy haired boss). I tried wrapping it with a caching layer like <%@ taglib uri="/WEB-INF/classes/oscache.tld" prefix="oscache" %> <oscache:cache time="60"> <div class="pagecontent"> ..... my logic </div> </oscache:cache> This is nice until the 60 seconds is over. The next query after that blocks until the 8 minutes of rendering is done with again. I would need a way to build a pattern something like: If there is no version of the dynamic content in the cache run the actual logic (and populate the cache for subsequent requests) If there is a non-expired version of the dynamic content in the cache serve the output of the JSP logic from the cache If there is an expired version of the dynamic content in the cache serve the output of the JSP logic still from the cache AND run the JSP logic in the background so that the cache gets updated transparently to the user - avoiding the user have to wait for 8 minutes I found out that at least EHCache might be able to do some asynchronous cache updating but it did not sadly seem to apply to the JSP tags... Also I have to take in 10-20 parameters for the actual logic of the JSP and some of them should be used as a key for caching. Code example and/or pointers would be greatly appreciated. I do not frankly care if the solution provided is extremely ugly. I just want a simple 5 minute caching with asynchronous cache update taking into account some parameters as a key.

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  • Customizing the TFS 2008 build sequence to avoid compilation and deploy SSRS

    - by Andrew
    I'm trying to create a CI process for SQL Server Reporting Services. I am fairly new to TFS but quite experienced with MSBuild. In the past I've used a combination of MSBuild with Team City so the whole build process is more or less custom. Here lies the start of my problems, as the solution I am deploying only contains Report Server projects (rds), no compilation is required. I thought that I would override the the first default task that TFS runs (EndToEndIteration) to override the default TFS build sequence and inject my own. The first snag that I have come across is that the build always fails, how can I set the status of the build to success? Currently the EndToEndIteration task is very light and only has a message. Is this the best method to create a custom build process in TFS where compilation is not required? Or should I use the default sequence and override one of the hook tasks mentioned in http://msdn.microsoft.com/en-us/library/aa337604%28VS.80%29.aspx (ie: AfterCompile) The core steps that I'd like to achieve are: Bundle the RDL and datasource files Connect to the host server to register/deploy the reports Re-apply any subscriptions that previously existed Run tests to verify the deployment succeeded and is returning results as expected I have found another article on Report services deployment: http://stackoverflow.com/questions/88710/reporting-services-deployment But it doesn't mention the best practice for customizing the standard build process. Any help would be appreciated.

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  • How to calculate this string-dissimilarity function efficiently?

    - by ybungalobill
    Hello, I was looking for a string metric that have the property that moving around large blocks in a string won't affect the distance so much. So "helloworld" is close to "worldhello". Obviously Levenshtein distance and Longest common subsequence don't fulfill this requirement. Using Jaccard distance on the set of n-grams gives good results but has other drawbacks (it's a pseudometric and higher n results in higher penalty for changing single character). [original research] As I thought about it, what I'm looking for is a function f(A,B) such that f(A,B)+1 equals the minimum number of blocks that one have to divide A into (A1 ... An), apply a permutation on the blocks and get B: f("hello", "hello") = 0 f("helloworld", "worldhello") = 1 // hello world -> world hello f("abba", "baba") = 2 // ab b a -> b ab a f("computer", "copmuter") = 3 // co m p uter -> co p m uter This can be extended for A and B that aren't necessarily permutations of each other: any additional character that can't be matched is considered as one additional block. f("computer", "combuter") = 3 // com uter -> com uter, unmatched: p and b. Observing that instead of counting blocks we can count the number of pairs of indices that are taken apart by a permutation, we can write f(A,B) formally as: f(A,B) = min { C(P) | P:|A|?|B|, P is bijective, ?i?dom(P) A[P(i)]=B[P(i)] } C(P) = |A| + |B| - |dom(P)| - |{ i | i,i+1?dom(P) and P(i)+1=P(i+1) }| - 1 The problem is... guess what... ... that I'm not able to calculate this in polynomial time. Can someone suggest a way to do this efficiently? Or perhaps point me to already known metric that exhibits similar properties?

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  • LinqToSql Select to a class then do more queries

    - by fyjham
    I have a LINQ query running with multiple joins and I want to pass it around as an IQueryable<T> and apply additional filters in other methods. The problem is that I can't work out how to pass around a var data type and keep it strongly typed, and if I try to put it in my own class (EG: .Select((a,b) => new MyClass(a,b))) I get errors when I try to add later Where clauses because my class has no translations into SQL. Is there any way I can do one of the following: Make my class map to SQL? Make the var data-type implement an interface (So I can pass it round as though it's that)? Something I haven't though of that'll solve my issue? Example: public void Main() { using (DBDataContext context = new DBDataContext()) { var result = context.TableAs.Join( context.TableBs, a => a.BID, b => b.ID, (a,b) => new {A = a, B = b} ); result = addNeedValue(result, 4); } } private ???? addNeedValue(???? result, int value) { return result.Where(r => r.A.Value == value); } PS: I know in my example I can flatten out the function easily, but in the real thing it'd be an absolute mess if I tried.

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  • What is the base open source java package to filter/match URLs?

    - by Boaz
    Hi, I have an high performance application which deals with URLs. For every URL it needs to retrieve the appropriate settings from a predefined pool. Every settings object is associated with a URL pattern which indicates which URLs should use these settings. The matching rules are as follows: "google.com" match pattern should match all URLs pointing to the google domain (thus, maps.google.com and www.google.com/match are matched). "*.google.com" should match all URLs pointing to a subdomain of google.com (thus, maps.google.com matches, but google.com and www.google.com don't). "maps.google.com" should match all URLs pointing to this specific subdomain. Apart from the above rules, every match rule can contain a path, which means that the path part of the URL should start with the match rule path. So: "*.google.com/maps" matches "maps.google.com/maps" but not "maps.google.com/advanced". As you can see the rules above are overlapping. In the case two rules exist which match the same URL the most specific should apply. The list above is ranked from least specific to most specific. This seems to be such a standard problem that I was hoping to use a ready made library rather than program my self. Google reveals a couple of options but without a clear way to choose between them. What would you recommend as a good library for this task? Thanks, Boaz

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  • How to get encoding from MAPI message with PR_BODY_A tag (windows mobile)?

    - by SadSido
    Hi, everyone! I am developing a program, that handles incoming e-mail and sms through windows-mobile MAPI. The code basically looks like that: ulBodyProp = PR_BODY_A; hr = piMessage->OpenProperty(ulBodyProp, NULL, STGM_READ, 0, (LPUNKNOWN*)&piStream); if (hr == S_OK) { // ... get body size in bytes ... STATSTG statstg; piStream->Stat(&statstg, 0); ULONG cbBody = statstg.cbSize.LowPart; // ... allocate memory for the buffer ... BYTE* pszBodyInBytes = NULL; boost::scoped_array<BYTE> szBodyInBytesPtr(pszBodyInBytes = new BYTE[cbBody+2]); // ... read body into the pszBodyInBytes ... } That works and I have a message body. The problem is that this body is multibyte encoded and I need to return a Unicode string. I guess, I have to use ::MultiByteToWideChar() function, but how can I guess, what codepage should I apply? Using CP_UTF8 is naive, because it can simply be not in UTF8. Using CP_ACP works, well, sometimes, but sometimes does not. So, my question is: how can I retrieve the information about message codepage. Does MAPI provide any functions for it? Or is there a way to decode multibyte string, other than MultiByteToWideChar()? Thanks!

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  • Iterating Over <select> Using jQuery + Multi Select

    - by Kezzer
    This isn't quite as straight forward as one may think. I'm using a plugin called jQuery MultiSelect and multiple <select options using XSLT as follows: <xsl:for-each select="RootField"> <select id="{RootField}" multiple="multiple" size="3"> <option value=""></option> <xsl:for-each select="ChildField"> <option value="{ChildField}"><xsl:value-of select="ChildField"/></option> </xsl:for-each> </select> </xsl:for-each> The accompanying JavaScript is as follows: var selects = document.getElementsByTagName("select"); $.each(selects, function() { $(this).multiSelect(); }); This allows me to apply the multiSelect(); function to every single <select on the page. The behaviour is quite strange, every other <select is being changed into the dropdown list (all the even ones anyway). I can't see anything wrong in my JavaScript to cause this issue as it would iterate over every single one. To make it more clear, the only lists that have that JavaScript applied to it are ones in position 2, 4, 6 and 8 (out of the 9 which are on the page). Any ideas?

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  • ASP.NET/C#: How to use a Subclassed Control on a Page?

    - by Bob Kaufman
    I've subclassed DropDownList to add functionality specific to my application: public class MyDropDownList : DropDownList { ... } ... then referenced it in Web.Config, which is where I figure things start to go wrong: <pages theme="Main"> <controls> <add tagPrefix="bob" tagName="MyDropDownList" src="~/Components/MyDropDownList.cs" /> </controls> </pages> my reference to it does not work: <tr><td>Category</td> <td><bob:MyDropDownList runat="server" ID="Category"... /> and my best clue is the complier error message: "The file 'src' is not a valid [sic] here because it doesn't expose a type." I figure I'm misapplying knowledge of how to create a Web User Control here. What I want to be able to do is refer to this control on an ASP.NET page just like I would the parent DropDownList. Refactoring back into a Web User Control that contains a DropDownList is not desirable, because I want to apply a RequiredFieldValidator to it.

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  • Performing calculations by subsets of data in R

    - by Vivi
    I want to perform calculations for each company number in the column PERMNO of my data frame, the summary of which can be seen here: > summary(companydataRETS) PERMNO RET Min. :10000 Min. :-0.971698 1st Qu.:32716 1st Qu.:-0.011905 Median :61735 Median : 0.000000 Mean :56788 Mean : 0.000799 3rd Qu.:80280 3rd Qu.: 0.010989 Max. :93436 Max. :19.000000 My solution so far was to create a variable with all possible company numbers compns <- companydataRETS[!duplicated(companydataRETS[,"PERMNO"]),"PERMNO"] And then use a foreach loop using parallel computing which calls my function get.rho() which in turn perform the desired calculations rhos <- foreach (i=1:length(compns), .combine=rbind) %dopar% get.rho(subset(companydataRETS[,"RET"],companydataRETS$PERMNO == compns[i])) I tested it for a subset of my data and it all works. The problem is that I have 72 million observations, and even after leaving the computer working overnight, it still didn't finish. I am new in R, so I imagine my code structure can be improved upon and there is a better (quicker, less computationally intensive) way to perform this same task (perhaps using apply or with, both of which I don't understand). Any suggestions?

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  • Using AND vs && in a for loop (Not related to precedence?)

    - by Peter
    Why is it that this code prints "Hello!" four times and then prints "1": <?php for ($i=1 AND $blah=1; $i<5; $i++) echo("Hello!"); echo($blah); ?> While this doesn't print out "Hello!" at all and then prints "1": <?php for ($i=1 && $blah=1; $i<5; $i++) echo("Hello!"); echo($blah); ?> I know AND and && have different precedences, but that doesn't seem to apply here. What am I missing? (I'm using a variant of the code above, since I will use $blah within the for loop, and I want to set the value for it). Thanks for any help!

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  • Flex NetConnection error: Property onDirtyList not found on flash.net.NetConnection

    - by David Wolever
    I'm having some trouble with NetConnection. The following code makes a connection without issue… var n:NetConnection = new NetConnection(); n.objectEncoding = ObjectEncoding.AMF0; n.addEventListener(NetStatusEvent.NET_STATUS, function(...args):void { trace("HERE"); }); n.connect("rtmp://...host...", ...args); But as soon as the NET_STATUS event handler finishes (ie, hitting "step into" with the debugger), I get this error: ReferenceError: Error #1069: Property onDirtyList not found on flash.net.NetConnection and there is no default value. Error #2044: Unhandled AsyncErrorEvent:. text=Error #2095: flash.net.NetConnection was unable to invoke callback onDirtyList. error=ReferenceError: Error #1069: Property onDirtyList not found on flash.net.NetConnection and there is no default value. at Test/___Test_Application1_creationComplete()[/Users/wolever/Workspace/Test/src/Test.mxml:13] at flash.events::EventDispatcher/dispatchEventFunction() at flash.events::EventDispatcher/dispatchEvent() at mx.core::UIComponent/dispatchEvent()[C:\autobuild\3.5.0\frameworks\projects\framework\src\mx\core\UIComponent.as:9440] at mx.core::UIComponent/set initialized()[C:\autobuild\3.5.0\frameworks\projects\framework\src\mx\core\UIComponent.as:1168] at mx.managers::LayoutManager/doPhasedInstantiation()[C:\autobuild\3.5.0\frameworks\projects\framework\src\mx\managers\LayoutManager.as:718] at Function/http://adobe.com/AS3/2006/builtin::apply() at mx.core::UIComponent/callLaterDispatcher2()[C:\autobuild\3.5.0\frameworks\projects\framework\src\mx\core\UIComponent.as:8744] at mx.core::UIComponent/callLaterDispatcher()[C:\autobuild\3.5.0\frameworks\projects\framework\src\mx\core\UIComponent.as:8684] Which is kind of scary because onDirtyList only yields two hits on Google. So... Any suggestions?

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  • HTML Submit button vs AJAX based Post (ASP.NET MVC)

    - by Graham
    I'm after some design advice. I'm working on an application with a fellow developer. I'm from the Webforms world and he's done a lot with jQuery and AJAX stuff. We're collaborating on a new ASP.MVC 1.0 app. He's done some pretty amazing stuff that I'm just getting my head around, and used some 3rd party tools etc. for datagrids etc. but... He rarely uses Submit buttons whereas I use them most of the time. He uses a button but then attaches Javascript to it that calls an MVC action which returns a JSON object. He then parses the object to update the datagrid. I'm not sure how he deals with server-side validation - I think he adds a message property to the JSON object. A sample scenario would be to "Save" a new record that then gets added to the gridview. The user doesn't see a postback as such, so he uses jQuery to disable the UI whilst the controller action is running. TBH, it looks pretty cool. However, the way I'd do it would be to use a Submit button to postback, let the ModelBinder populate a typed model class, parse that in my controller Action method, update the model (and apply any validation against the model), update it with the new record, then send it back to be rendered by the View. Unlike him, I don't return a JSON object, I let the View (and datagrid) bind to the new model data. Both solutions "work" but we're obviously taking the application down different paths so one of us has to re-work our code... and we don't mind whose has to be done. What I'd prefer though is that we adopt the "industry-standard" way of doing this. I'm unsure as to whether my WebForms background is influencing the fact that his way just "doesn't feel right", in that a "submit" is meant to submit data to the server. Any advice at all please - many thanks.

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  • Is it possible for a function called from within an object to have access to that object's scope?

    - by Elliot Bonneville
    I can't think of a way to explain what I'm after more than I've done in the title, so I'll repeat it. Is it possible for an anonymous function called from within an object to have access to that object's scope? The following code block should explain what I'm trying to do better than I can: function myObj(testFunc) { this.testFunc = testFunc; this.Foo = function Foo(test) { this.test = test; this.saySomething = function(text) { alert(text); }; }; var Foo = this.Foo; this.testFunc.apply(this); } var test = new myObj(function() { var test = new Foo(); test.saySomething("Hello world"); }); When I run this, I get an error: "Foo is not defined." How do I ensure that Foo will be defined when I call the anonymous function? Here's a jsFiddle for further experimentation. Edit: I am aware of the fact that adding the line var Foo = this.Foo; to the anonymous function I pass in to my instance of myObj will make this work. However, I'd like to avoid having to expose the variable inside the anonymous function--do I have any other options?.

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  • How to access elements in a complex list?

    - by Martin
    Hi, it's me and the lists again. I have a nice list, which looks like this: tmp = NULL t = NULL tmp$resultitem$count = "1057230" tmp$resultitem$status = "Ok" tmp$resultitem$menu = "PubMed" tmp$resultitem$dbname = "pubmed" t$resultitem$count = "305215" t$resultitem$status = "Ok" t$resultitem$menu = "PMC" t$resultitem$dbname = "pmc" tmp = c(tmp, t) t = NULL t$resultitem$count = "1" t$resultitem$status = "Ok" t$resultitem$menu = "Journals" t$resultitem$dbname = "journals" tmp = c(tmp, t) Which produces: str(tmp) List of 3 $ resultitem:List of 4 ..$ count : chr "1057230" ..$ status: chr "Ok" ..$ menu : chr "PubMed" ..$ dbname: chr "pubmed" $ resultitem:List of 4 ..$ count : chr "305215" ..$ status: chr "Ok" ..$ menu : chr "PMC" ..$ dbname: chr "pmc" $ resultitem:List of 4 ..$ count : chr "1" ..$ status: chr "Ok" ..$ menu : chr "Journals" ..$ dbname: chr "journals" Now I want to search through the elements of each "resultitem". I want to know the "dbname" for every database, that has less then 10 "count" (example). In this case it is very easy, as this list only has 3 elements, but the real list is a little bit longer. This could be simply done with a for loop. But is there a way to do this with some other function of R (like rapply)? My problem with those apply functions is, that they only look at one element. If I do a grep to get all "dbname" elements, I can not get the count of each element. rapply(tmp, function(x) paste("Content: ", x))[grep("dbname", names(rapply(tmp, c)))] Does someone has a better idea than a for loop? Thanx, Martin

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  • Analyzing Web Application Speed

    - by Amy
    I'm a bit confused because the logical/programmer brain in me says that if all things are constant, the speed of a function must be constant. I am working on a PHP web application with jqGrid as a front end for showing the data. I am testing on my personal computer, so network traffic does not apply. I make an HTTP request to a PHP function, it returns the data, and then jqGrid renders it. What has me befuddled is that sometimes, Firebug reports that this is taking 300-600 milliseconds sometimes, and sometimes, it's taking 3.68 seconds. I can run the request over and over again, with very radically different response times. The query is the same. The number of users on the system is the same. No network latency. Same code. I'm not running other applications on the computer while testing. I could understand query caching improving performance on subsequent requests, but the speed is just fluctuating wildly with no rhyme or reason. So, my question is, what else can cause such variability in the response time? How can I determine what's doing it? More importantly, is there any way to get things more consistent?

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  • SEO, ordering and duplication of content

    - by piquadrat
    I run a specialized news site and am trying to apply a little bit of SEO sauce to it. One of the most important things I hear is to avoid duplication of content. I've covered all the basics but I'm stuck with ordering of content. As an example, the archive of the site is orderable by date, views, and rating. Since we don't have that many news items, an archive page for a particular day has usually only a couple of items, so the following URLs all have the same content, albeit in different ordering: /news/archive/2010/05/16/ /news/archive/2010/05/16/?o=views /news/archive/2010/05/16/?o=rating Do search machines penalize this particular kind of duplication of content? And if yes, what's the best way to avoid said penalty? <link rel="canonical" />? Tell Google & Co. to ingore the o parameter? Marking the ordering links with nofollow? Only allow the indexation of the date-ordered archive sites through robots.txt (not sure if this is even possible)?

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  • How to bind data from a view of type List<List<MyViewModelClass>>?

    - by Robert Koritnik
    I have a strong type view of type List<List<MyViewModelClass>> The outer list will always have two lists of List<MyViewModelClass>. For each of the two outer lists I want to display a group of checkboxes. Each set can have an arbitrary number of choices. My view model class looks similar to this: public class MyViewModelClass { public Area Area { get; set; } public bool IsGeneric { get; set; } public string Code { get; set; } public bool IsChecked { get; set; } } So the final view will look something like: Please select those that apply: First set of choices: x Option 1 x Option 2 x Option 3 etc. Second set of choices: x Second Option 1 x Second Option 2 x Second Option 3 x Second Option 4 etc. Checkboxes should display MyViewModelClass.Area.Name, and their value should be related to MyViewModelClass.Area.Id. Checked state is of course related to MyViewModel.IsChecked. Question I wonder how should I use Html.CheckBox() or Html.CheckBoxFor() helper to display my checkboxes? I have to get these values back to the server on a postback of course. If it makes things simpler, I could make a separate view model type like: public class Options { public List<MyViewModelClass> General { get; set; } public List<MyViewModelClass> Others { get; set; } }

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  • too much recursion in javascript with jquery mouseover

    - by Stacia
    I am a JS novice. Using some code I found here to help me with mouseover scale/rotate images but now when I try to apply it to more than one object I'm getting errors saying "too much recursion". Before the function didn't take any arguments, it just was on s_1 and it worked fine. I am tempted to just write different code for each object but that isn't very good programming practice. var over = false; $(function(){ $("#s_1").hover(function(){ over = true; swing_left_anim("#s_1"); }, function(){ over = false; }); $("#np_1").hover(function(){ over = true; swing_left_anim("np_1"); }, function(){ over = false; }); }); function swing_left_anim(obj){ $(obj).animate({ rotate: '0deg' }, { duration: 500 }); if (over) { $(obj).animate({ rotate: '25deg' }, 500, swing_right_anim(obj)); } } function swing_right_anim(obj){ $(obj).animate({ rotate: '-25deg' }, 500, swing_left_anim(obj)); }

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  • xml to hashmap - php

    - by csU
    Hi, Given an xml structure like this <gesmes:Envelope> <gesmes:subject>Reference rates</gesmes:subject> <gesmes:Sender> <gesmes:name>European Central Bank</gesmes:name> </gesmes:Sender> <Cube> <Cube time="2010-03-26"> <Cube currency="USD" rate="1.3353"/> <Cube currency="JPY" rate="124.00"/> <Cube currency="BGN" rate="1.9558"/> <Cube currency="CZK" rate="25.418"/> ... ... </Cube> </Cube> </gesmes:Envelope> how can i go about getting the values stored in to a hashmap or similar structure in php? Have been trying to do this for the last few hours now but cant manage it :D It is homework so i guess no full solutuins please( tho the actual assignment is to use the web services, i am just stuck with parsing it :D ). Maybe someone could show me a brief example for a made up xml file that i could apply to mine? Thanks

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  • more problems with the LAG function is SAS

    - by SAS_learner
    The following bit of SAS code is supposed to read from a dataset which contains a numeric variable called 'Radvalue'. Radvalue is the temperature of a radiator, and if a radiator is switched off but then its temperature increases by 2 or more it's a sign that it has come on, and if it is on but its temperature decreases by 2 or more it's a sign that it's gone off. Radstate is a new variable in the dataset which indicates for every observation whether the radiator is on or off, and it's this I'm trying to fill in automatically for the whole dataset. So I'm trying to use the LAG function, trying to initialise the first row, which doesn't have a dif_radvalue, and then trying to apply the algorithm I just described to row 2 onwards. Any idea why the columns Radstate and l_radstate come out completely blank? Thanks everso much!! Let me know if I haven't explained the problem clearly. Data work.heating_algorithm_b; Input ID Radvalue; Datalines; 1 15.38 2 15.38 3 20.79 4 33.47 5 37.03 ; DATA temp.heating_algorithm_c; SET temp.heating_algorithm_b; DIF_Radvalue = Radvalue - lag(Radvalue); l_Radstate = lag(Radstate); if missing(dif_radvalue) then do; dif_radvalue = 0; radstate = "off"; end; else if l_Radstate = "off" & DIF_Radvalue > 2 then Radstate = "on"; else if l_Radstate = "on" & DIF_Radvalue < -2 then Radstate = "off"; else Radstate = l_Radstate; run;

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  • How are you using C++0x today? [closed]

    - by Roger Pate
    This is a question in two parts, the first is the most important and concerns now: Are you following the design and evolution of C++0x? What blogs, newsgroups, committee papers, and other resources do you follow? Even where you're not using any new features, how have they affected your current choices? What new features are you using now, either in production or otherwise? The second part is a follow-up, concerning the new standard once it is final: Do you expect to use it immediately? What are you doing to prepare for C++0x, other than as listed for the previous questions? Obviously, compiler support must be there, but there's still co-workers, ancillary tools, and other factors to consider. What will most affect your adoption? Edit: The original really was too argumentative; however, I'm still interested in the underlying question, so I've tried to clean it up and hopefully make it acceptable. This seems a much better avenue than duplicating—even though some answers responded to the argumentative tone, they still apply to the extent that they addressed the questions, and all answers are community property to be cleaned up as appropriate, too.

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  • C++0x rvalue references and temporaries

    - by Doug
    (I asked a variation of this question on comp.std.c++ but didn't get an answer.) Why does the call to f(arg) in this code call the const ref overload of f? void f(const std::string &); //less efficient void f(std::string &&); //more efficient void g(const char * arg) { f(arg); } My intuition says that the f(string &&) overload should be chosen, because arg needs to be converted to a temporary no matter what, and the temporary matches the rvalue reference better than the lvalue reference. This is not what happens in GCC and MSVC. In at least G++ and MSVC, any lvalue does not bind to an rvalue reference argument, even if there is an intermediate temporary created. Indeed, if the const ref overload isn't present, the compilers diagnose an error. However, writing f(arg + 0) or f(std::string(arg)) does choose the rvalue reference overload as you would expect. From my reading of the C++0x standard, it seems like the implicit conversion of a const char * to a string should be considered when considering if f(string &&) is viable, just as when passing a const lvalue ref arguments. Section 13.3 (overload resolution) doesn't differentiate between rvalue refs and const references in too many places. Also, it seems that the rule that prevents lvalues from binding to rvalue references (13.3.3.1.4/3) shouldn't apply if there's an intermediate temporary - after all, it's perfectly safe to move from the temporary. Is this: Me misreading/misunderstand the standard, where the implemented behavior is the intended behavior, and there's some good reason why my example should behave the way it does? A mistake that the compiler vendors have somehow all made? Or a mistake based on common implementation strategies? Or a mistake in e.g. GCC (where this lvalue/rvalue reference binding rule was first implemented), that was copied by other vendors? A defect in the standard, or an unintended consequence, or something that should be clarified?

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  • Hierarchy of meaning

    - by asldkncvas
    I am looking for a method to build a hierarchy of words. Background: I am a "amateur" natural language processing enthusiast and right now one of the problems that I am interested in is determining the hierarchy of word semantics from a group of words. For example, if I have the set which contains a "super" representation of others, i.e. [cat, dog, monkey, animal, bird, ... ] I am interested to use any technique which would allow me to extract the word 'animal' which has the most meaningful and accurate representation of the other words inside this set. Note: they are NOT the same in meaning. cat != dog != monkey != animal BUT cat is a subset of animal and dog is a subset of animal. I know by now a lot of you will be telling me to use wordnet. Well, I will try to but I am actually interested in doing a very domain specific area which WordNet doesn't apply because: 1) Most words are not found in Wordnet 2) All the words are in another language; translation is possible but is to limited effect. another example would be: [ noise reduction, focal length, flash, functionality, .. ] so functionality includes everything in this set. I have also tried crawling wikipedia pages and applying some techniques on td-idf etc but wikipedia pages doesn't really do much either. Can someone possibly enlighten me as to what direction my research should go towards? (I could use anything)

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  • SCJP Book, IO section: Is this a typo or is there a reason it would look like this?

    - by iamchuckb
    My question is about line 4, where the new PrintWriter is created with the constructor taking the FileWriter fw as a parameter. I don't understand the use of chaining the BufferedWriter bw to FileWriter if it isn't used later on in the actual writing. Can Java apply chaining in a way that bw still somehow affects the rest of the program? 16. try { 17. FileWriter fw = new FileWriter(test); 18. BufferedWriter bw = new BufferedWriter(fw, 1024); 19. PrintWriter out = new PrintWriter(fw); 20. out.println("<html><body><h1>"); 21. out.println(args[0]); 22. out.println("</h1></body></html>"); 23. out.close(); 24. bw.close(); 25. fw.close(); 26. }catch(IOException e) { 27. e.printStackTrace(); 28. } I think it is probably a typo and they meant to use bw as the parameter for PrintWriter out but like the title says, I'm new to this. Thanks to all in advance.

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  • Count the no of LI then add class to parent UL.

    - by Wazdesign
    <ul class="taglib-ratings thumbs"> <li id="qezr_yourRating"> <a href="javascript:;" class="rating rate-up "></a> </li> </ul> <ul class="taglib-ratings thumbs"> <li id="qezr_yourRating"> <a href="javascript:;" class="rating rate-up "></a> </li> <li id="qezr_yourRating"> <a href="javascript:;" class="rating rate-up "></a> </li> </ul> I want to apply the class to the UL on base of the Count of the Inner LIs. Like if it has two LI then the class should be like two-thumbs Like if it has one LI then the class should be like one-thumbs I am trying this JS but not working it returns 2 jQuery(document).ready(function(){ var countLi = $(".taglib-ratings > li").size(); alert(countLi); if(countLi == 2) { $(this).parent('.taglib-ratings').addClass('2-col'); alert ('this ul has 2 li'); } else if(countLi == 1) { $(this).parent('.taglib-ratings').addClass('2-col'); alert ('this ul has 1 li'); } else if(countLi > 2) { alert ('this ul has'+ countLi +' li'); } }); Here is the JSbin link to the same. http://jsbin.com/ofeda/edit

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