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  • Static Variables somehow maintaining state?

    - by gfoley
    I am working on an existing project, setup by another coder. I'm having some trouble understanding how state is being maintained between pages. There is a Class library which has some helper objects. Mostly these objects are just used for there static methods and rarely instantiated or inherited. This is an example class I'm testing with. public sealed class Application { public static string Test; } Now when i run something like the following in the base class of my page, I would expect the result to be "1: 2:Test" all the time (note that "1" is empty), but strangly its only this way the first time it is run. Then every time afterwards its "1:Test 2:Test". Somehow its maintaining the state of the static variable between pages and being refreshed?? Response.Write("1:" + SharedLibrary.Application.Test); SharedLibrary.Application.Test = "Test"; Response.Write(" 2:" + SharedLibrary.Application.Test); I need to create more classes like this, but want to understand why this is occurring in the first place. Many Thanks

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  • XSLT - How to select top a to top b

    - by user812241
    how can I extract the first 2 C-Values ('Baby' and 'Cola') where B is 'RED'. Input instance is: <Root> <A> <B>BLACK</B> <C>Apple</C> </A> <A> <B>RED</B> <C>Baby</C> </A> <A> <B>GREEN</B> <C>Sun</C> </A> <A> <B>RED</B> <C>Cola</C> </A> <A> <B>RED</B> <C>Mobile</C> </A> </Root> Output instance must be: <Root> <D>Baby</D> <D>Cola</D> </Root> I thought about the combination of for-each and global variables. But in XSLT it is not possible to change the value for a global variable to break the for-each. I have no idea anymore.

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  • How can I modified the value of a string defined in a struc?

    - by Eric
    Hi, I have the following code in c++: define TAM 4000 define NUMPAGS 512 struct pagina { bitset<12 direccion; char operacion; char permiso; string *dato; int numero; }; void crearPagina(pagina* pag[], int pos, int dir) { pagina * paginas = (pagina*)malloc(sizeof(char) * TAM); paginas - direccion = bitset<12 (dir); paginas - operacion = 'n'; paginas - permiso = 'n'; string **tempDato = &paginas - dato; char *temp = " "; **tempDato = temp; paginas - numero = 0; pag[pos] = paginas; } I want to modify the value of the variable called "string *dato" in the struct pagina but, everytime I want to assing a new value, the compiler throws a segmentation fault. In this case I'm using a pointer to string, but I have also tried with a string. In a few words I want to do the following: pagina - dato = "test"; Any idea? Thanks in advance!!!

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  • Trouble determining onclick's target

    - by pwseo
    I've tried and tried... and I can't seem to make this work in IE (tested version 6) Can anybody help me? IE complains about an error but refuses to tell which error it is... var a = document.getElementsByTagName("a"); for (i = 0; i < a.length; i++) { if (a[i].getAttribute("class") == "info-link") { a[i].onclick = function(e) { e = e || window.event; var target = e.srcElement || e.target; var info = target.parentNode.getElementsByTagName("div")[0]; if (info.style.display == "none" || info.style.display == "") { info.style.display = "block"; } else { info.style.display = "none"; } return false; } } } <div class="auxdata"> <a href="#" class="info-link">Esta questão possuí dados anexos. Clique para ver.</a> <div style="display: none;" class="info-inner"> <!-- variable stuff here --> </div> </div>

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  • map operator [] operands

    - by Jamie Cook
    Hi all I have the following in a member function int tt = 6; vector<set<int>>& temp = m_egressCandidatesByDestAndOtMode[tt]; set<int>& egressCandidateStops = temp.at(dest); and the following declaration of a member variable map<int, vector<set<int>>> m_egressCandidatesByDestAndOtMode; However I get an error when compiling (Intel Compiler 11.0) 1>C:\projects\svn\bdk\Source\ZenithAssignment\src\Iteration\PtBranchAndBoundIterationOriginRunner.cpp(85): error: no operator "[]" matches these operands 1> operand types are: const std::map<int, std::vector<std::set<int, std::less<int>, std::allocator<int>>, std::allocator<std::set<int, std::less<int>, std::allocator<int>>>>, std::less<int>, std::allocator<std::pair<const int, std::vector<std::set<int, std::less<int>, std::allocator<int>>, std::allocator<std::set<int, std::less<int>, std::allocator<int>>>>>>> [ const int ] 1> vector<set<int>>& temp = m_egressCandidatesByDestAndOtMode[tt]; 1> ^ I know it's got to be something silly but I can't see what I've done wrong.

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  • Rename files and directories using substitution and variables

    - by rednectar
    I have found several similar questions that have solutions, except they don't involve variables. I have a particular pattern in a tree of files and directories - the pattern is the word TEMPLATE. I want a script file to rename all of the files and directories by replacing the word TEMPLATE with some other name that is contained in the variable ${newName} If I knew that the value of ${newName} was say "Fred lives here", then the command find . -name '*TEMPLATE*' -exec bash -c 'mv "$0" "${0/TEMPLATE/Fred lives here}"' {} \; will do the job However, if my script is: newName="Fred lives here" find . -name '*TEMPLATE*' -exec bash -c 'mv "$0" "${0/TEMPLATE/${newName}}"' {} \; then the word TEMPLATE is replaced by null rather than "Fred lives here" I need the "" around $0 because there are spaces in the path name, so I can't do something like: find . -name '*TEMPLATE*' -exec bash -c 'mv "$0" "${0/TEMPLATE/"${newName}"}"' {} \; Can anyone help me get this script to work so that all files and directories that contain the word TEMPLATE have TEMPLATE replaced by whatever the value of ${newName} is eg, if newName="A different name" and a I had directory of /foo/bar/some TEMPLATE directory/with files then the directory would be renamed to /foo/bar/some A different name directory/with files and a file called some TEMPLATE file would be renamed to some A different name file

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  • Best method to select an object from another unknown jQuery object

    - by Yosi
    Lets say I have a jQuery object/collection stored in a variable named obj, which should contain a DOM element with an id named target. I don't know in advance if target will be a child in obj, i.e.: obj = $('<div id="parent"><div id="target"></div></div>'); or if obj equals target, i.e.: obj = $('<div id="target"></div>'); or if target is a top-level element inside obj, i.e.: obj = $('<div id="target"/><span id="other"/>'); I need a way to select target from obj, but I don't know in advance when to use .find and when to use .filter. What would be the fastest and/or most concise method of extracting target from obj? What I've come up with is: var $target = obj.find("#target").add(obj.filter("#target")); UPDATE I'm adding solutions to a JSPERF test page to see which one is the best. Currently my solution is still the fastest. Here is the link, please run the tests so that we'll have more data: http://jsperf.com/jquery-selecting-objects

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  • WCF Custom SOAP Header Issues

    - by WayneC
    I'm trying to implement an endpoint behavior which injects a custom SOAP header into all messages to and from a service. I've gotten pretty close by implementing the approach from the accepted answer of this question: http://stackoverflow.com/questions/986455/wcf-wsdl-soap-header-on-all-operations/995951#995951 After implementing that solution, my custom SOAP header does indeed show up in the WSDL; however, when I try to call the methods on my service, I get the following exception/fault: <ExceptionDetail xmlns="http://schemas.datacontract.org/2004/07/System.ServiceModel" xmlns:i="http://www.w3.org/2001/XMLSchema-instance"> <HelpLink i:nil="true" /> <InnerException i:nil="true" /> <Message>Index was outside the bounds of the array.</Message> <StackTrace> at System.ServiceModel.Dispatcher.DataContractSerializerOperationFormatter.AddHeadersToMessage(Message message, MessageDescription messageDescription, Object[] parameters, Boolean isRequest) at System.ServiceModel.Dispatcher.OperationFormatter.SerializeReply(MessageVersion messageVersion, Object[] parameters, Object result) at System.ServiceModel.Dispatcher.DispatchOperationRuntime.SerializeOutputs(MessageRpc&amp; rpc) at System.ServiceModel.Dispatcher.DispatchOperationRuntime.InvokeBegin(MessageRpc&amp; rpc) at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage5(MessageRpc&amp; rpc) at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage4(MessageRpc&amp; rpc) at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage3(MessageRpc&amp; rpc) at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage2(MessageRpc&amp; rpc) at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage1(MessageRpc&amp; rpc) at System.ServiceModel.Dispatcher.MessageRpc.Process(Boolean isOperationContextSet)</StackTrace> <Type>System.IndexOutOfRangeException</Type> </ExceptionDetail> Looking in Reflector at the DataContractSerializerOperationFormatter.AddHeadersToMessage method thats throwing the exception, leads me to believe that the following snippet is causing the problem...but I'm not sure why. MessageHeaderDescription description = (MessageHeaderDescription) headerPart.Description; object parameterValue = parameters[description.Index]; I think the last line above is throwing the exception. The parameters variable is from IDispatchFormatter.SerializeReply What's going on?!?!! Any help would be greatly appreciated...

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  • callbacks via objective-c selectors

    - by codemonkey
    I have a "BSjax" class that I wrote that lets me make async calls to our server to get json result sets, etc using the ASIHTTPRequest class. I set it up so that the BSjax class parses my server's json response, then passes control back to the calling view controller via this call: [[self delegate] performSelectorOnMainThread:@selector(bsRequestFinished:) withObject:self waitUntilDone:YES]; ... where "bsRequestFinished" is the callback method in the calling view controller. This all worked fine and well until I realized that some pages are going to need to make different types of requests... i.e. I'll want to do different types of things in that callback function depending on which type of request was made. To me it seems like being able to pass different callback function names to my BSjax class would be the cleanest fix... but I'm having trouble (and am not even sure if it's possible) to pass in a variable that holds the callback function name and then replace the call above with something like this: [[self delegate] performSelectorOnMainThread:@selector(self.variableCallbackFunctionName) withObject:self waitUntilDone:YES]; ... where "self.variableCallbackFunctionName" is set by the calling view controller when it calls BSjax to make a new request. Is this even possible? If so, advisable? If not, alternatives? EDIT: Note that whatever fix I arrive at will need to take into account the reality that this class is making async requests... so I need to make sure that the callback function processing is correctly tied to the specific requests... as I can't rely on FIFO processing sequence.

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  • How can I format Custom Data and display in autocomplete when source is an DB

    - by Andres Scarpone
    so I'm trying to get some info in the auto-complete widget like it's shown in the JQuery UI demo Demo, the only problem is they use a variable that they fill with the data they want to show, I instead want to access the data and the different description and stuff using a Data Base in MySQL, for this I have changed the source to use another php page that looks up the info. here is the code for the Auto-complete, I really don't understand the methods so I haven't changed it from the basic search. This is the JS: $(document).ready((function(){ $( "#completa" ).autocomplete({ source: "buscar.php", minLength: 1, focus: function (event, ui){ $("#completa").val(ui.item.val); return false; }; })); This is what I have in buscar.php: <?php $conec = mysql_connect(localhost, root, admin); if(!$conec) { die(mysql_error()); } else { $bd = mysql_select_db("ve_test",$conec ); if(!$bd) { die(mysql_error()); } } $termino = trim(strip_tags($_GET['term']));//Obtener el termino que envia el autocompletar $qstring = "SELECT name, descripcion FROM VE_table WHERE name LIKE '%".$termino."%'"; $result = mysql_query($qstring);//Solicitud a la Base de Datos while ($row = mysql_fetch_array($result,MYSQL_ASSOC))//Realizar un LOOP sobre los valores obtenidos { $row['value']=htmlentities(stripslashes($row['name'])); $row_set[] = $row;//build an array } echo json_encode($row_set);//Enviar los datos al autocompletar en codificacion JSON, Altamente Necesario. ?

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  • Problems installing PIL after OSX 10.9

    - by user2632417
    I installed Mac OSX 10.9 the day it came out. Afterwards I decided I needed to install PIL. I'd installed it before, but it appeared the update had broken that. When I try to use pip to install PIL, it fails when building _imaging. It appears the root cause is this. /usr/include/sys/cdefs.h:655:2: error: Unsupported architecture Theres also a similar error here: /usr/include/machine/limits.h:8:2: error: architecture not supported and here: /usr/include/machine/_types.h:34:2: error: architecture not supported Then there's a whole list of missing types. /usr/include/sys/_types.h:94:9: error: unknown type name '__int64_t' typedef __int64_t __darwin_blkcnt_t; /* total blocks */ ^ /usr/include/sys/_types.h:95:9: error: unknown type name '__int32_t' typedef __int32_t __darwin_blksize_t; /* preferred block size */ ^ /usr/include/sys/_types.h:96:9: error: unknown type name '__int32_t' typedef __int32_t __darwin_dev_t; /* dev_t */ ^ /usr/include/sys/_types.h:99:9: error: unknown type name '__uint32_t' typedef __uint32_t __darwin_gid_t; /* [???] process and group IDs */ ^ /usr/include/sys/_types.h:100:9: error: unknown type name '__uint32_t' typedef __uint32_t __darwin_id_t; /* [XSI] pid_t, uid_t, or gid_t*/ ^ /usr/include/sys/_types.h:101:9: error: unknown type name '__uint64_t' typedef __uint64_t __darwin_ino64_t; /* [???] Used for 64 bit inodes */ Needless to say I don't know where to go from here. I've got a couple of guesses, but I don't even know how to check. Wrong include probably as a result of a badly configured environment variable Problem with Xcode's installation/ missing command line tools Messed up header files If anyone has any suggestions either to check one of those possibilities or for one of their own I'm all ears.

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  • Is there a way to get the PREMATCH ($`) and POSTMATCH ($') from pcrecpp?

    - by Eric Peers
    Is there a way to obtain the C++ equivalent of Perl's PREMATCH ($`) and POSTMATCH ($') from pcrecpp? I would be happy with a string, a char *, or pairs indices/startpos+length that point at this. StringPiece seems like it might accomplish part of this, but I'm not certain how to get it. in perl: $_ = "Hello world"; if (/lo\s/) { $pre = $`; #should be "Hel" $post = $'; #should be "world" } in C++ I would have something like: string mystr = "Hello world"; //do I need to map this in a StringPiece? if (pcrecpp::RE("lo\s").PartialMatch(mystr)) { //should I use Consume or FindAndConsume? //What should I do here to get pre+post matches??? } pcre plainjane c seems to have the ability to return the vector with the matches including the "end" portion of the string, so I could theoretically extract such a pre/post variable, but that seems like a lot of work. I like the simplicty of the pcrecpp interface. Suggestions? Thanks! --Eric

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  • Constructor being called again?

    - by Halo
    I have this constructor; public UmlDiagramEntity(ReportElement reportElement, int pageIndex, Controller controller) { super(reportElement.getX1(), reportElement.getY1(), reportElement.getX2(), reportElement.getY2()); setLayout(null); this.pageIndex = pageIndex; this.controller = controller; reportElements = reportElement.getInternalReportElements(); components = new ArrayList<AbstractEntity>(); changedComponentIndex = -1; PageListener p = new PageListener(); this.addMouseMotionListener(p); this.addMouseListener(p); setPage(); } And I have an update method in the same class; @Override public void update(ReportElement reportElement) { if (changedComponentIndex == -1) { super.update(reportElement); } else { reportElements = reportElement.getInternalReportElements(); if (components.size() == reportElements.size()) { if (!isCommitted) { if (reportElement.getType() == ReportElementType.UmlRelation) { if (checkInvolvementAndSet(changedComponentIndex)) { anchorEntity(changedComponentIndex); } else { resistChanges(changedComponentIndex); } return; } } ..................goes on When I follow the flow from the debugger, I see that when update is called, somewhere in the method, the program goes into the constructor and executes it all over again (super, pageIndex, etc.). Why does it go to the constructor :D I didn't tell it to go there. I can make a deeper analysis and see where it goes to the constructor if you want. By the way, changedComponentIndex is a static variable.

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  • define a closure as method from class

    - by user272839
    Hi, i'm trying to play with php5.3 and closure. I see here (Listing 7. Closure inside an object : http://www.ibm.com/developerworks/opensource/library/os-php-5.3new2/index.html) that it's possible to use $this in the callback function, but it's not. So I try to give $this as use variable : $self = $this; $foo = function() use($self) { //do something with $self } So to use the same example : class Dog { private $_name; protected $_color; public function __construct($name, $color) { $this->_name = $name; $this->_color = $color; } public function greet($greeting) { $self = $this; return function() use ($greeting, $self) { echo "$greeting, I am a {$self->_color} dog named {$self->_name}."; }; } } $dog = new Dog("Rover","red"); $dog->greet("Hello"); Output: Hello, I am a red dog named Rover. First of all this example does not print the string but return the function, but that's not my problem. Secondly I can't access to private or protected, because the callback function is a global function and not in the context from the Dog object. Tha't my problem. It's the same as : function greet($greeting, $object) { echo "$greeting, I am a {$self->_color} dog named {$self->_name}."; } And I want : public function greet($greeting) { echo "$greeting, I am a {$self->_color} dog named {$self->_name}."; } Which is from Dog and not global. I hope that I am clear ...

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  • Accessing global variables of custom controls in ASP.NET

    - by CL4NCY
    Hi, I have built lots of custom asp.net controls which work really well separately but I want to somehow allow global access to all their variables from anywhere on the page. I have a central control called the ContentManager which I can use to store these variables. The problem I have is that all the controls are bound at different times so I only want the variables available after they're bound. For example I have many custom repeaters on the page which when bound I want to add a reference in the content manager so all their variables are then available to use. <Custom:ContentManager ID="cm" runat="server"/> <Custom:Repeater ID="r1" runat="server"/> <Custom:Repeater ID="r2" runat="server"/> <Custom:Repeater ID="r3" runat="server"/> Then I want a tag which can access all variables from any of these controls. <%= cm.controls["r1"].Items[0]["name"] %> The problem with this is that the variable isn't available until the repeater is bound so I might need to use events to push out the value to tags on the page like so: <Custom:Var ID="v1" control="r1" value="Items[0]["name"]" runat="server"/> Is this possible or can you recommend a better approach?

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  • How do actually castings work at the CLR level?

    - by devoured elysium
    When doing an upcast or downcast, what does really happen behind the scenes? I had the idea that when doing something as: string myString = "abc"; object myObject = myString; string myStringBack = (string)myObject; the cast in the last line would have as only purpose tell the compiler we are safe we are not doing anything wrong. So, I had the idea that actually no casting code would be embedded in the code itself. It seems I was wrong: .maxstack 1 .locals init ( [0] string myString, [1] object myObject, [2] string myStringBack) L_0000: nop L_0001: ldstr "abc" L_0006: stloc.0 L_0007: ldloc.0 L_0008: stloc.1 L_0009: ldloc.1 L_000a: castclass string L_000f: stloc.2 L_0010: ret Why does the CLR need something like castclass string? There are two possible implementations for a downcast: You require a castclass something. When you get to the line of code that does an castclass, the CLR tries to make the cast. But then, what would happen had I ommited the castclass string line and tried to run the code? You don't require a castclass. As all reference types have a similar internal structure, if you try to use a string on an Form instance, it will throw an exception of wrong usage (because it detects a Form is not a string or any of its subtypes). Also, is the following statamente from C# 4.0 in a Nutshell correct? Upcasting and downcasting between compatible reference types performs reference conversions: a new reference is created that points to the same object. Does it really create a new reference? I thought it'd be the same reference, only stored in a different type of variable. Thanks

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  • Open an Emacs buffer when a command tries to open an editor in shell-mode

    - by Chris Conway
    I like to use Emacs' shell mode, but it has a few deficiencies. One of those is that it's not smart enough to open a new buffer when a shell command tries to invoke an editor. For example with the environment variable VISUAL set to vim I get the following from svn propedit: $ svn propedit svn:externals . "svn-prop.tmp" 2L, 149C[1;1H ~ [4;1H~ [5;1H~ [6;1H~ [7;1H~ ... (It may be hard to tell from the representation, but it's a horrible, ugly mess.) With VISUAL set to "emacs -nw", I get $ svn propedit svn:externals . emacs: Terminal type "dumb" is not powerful enough to run Emacs. It lacks the ability to position the cursor. If that is not the actual type of terminal you have, use the Bourne shell command `TERM=... export TERM' (C-shell: `setenv TERM ...') to specify the correct type. It may be necessary to do `unset TERMINFO' (C-shell: `unsetenv TERMINFO') as well.svn: system('emacs -nw svn-prop.tmp') returned 256 (It works with VISUAL set to just emacs, but only from inside an Emacs X window, not inside a terminal session.) Is there a way to get shell mode to do the right thing here and open up a new buffer on behalf of the command line process?

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  • Java downcasting dilemma

    - by Shades88
    please have a look at this code here. class Vehicle { public void printSound() { System.out.print("vehicle"); } } class Car extends Vehicle { public void printSound() { System.out.print("car"); } } class Bike extends Vehicle{ public void printSound() { System.out.print("bike"); } } public class Test { public static void main(String[] args) { Vehicle v = new Car(); Bike b = (Bike)v; v.printSound(); b.printSound(); Object myObj = new String[]{"one", "two", "three"}; for (String s : (String[])myObj) System.out.print(s + "."); } } Executing this code will give ClassCastException saying inheritance.Car cannot be cast to inheritance.Bike. Now look at the line Object myObj = new String[]{"one", "two", "three"};. This line is same as Vehicle v = new Car(); right? In both lines we are assigning sub class object to super class reference variable. But downcasting String[]myObj is allowed but (Bike)v is not. Please help me understand what is going on around here.

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  • C++: defining maximum/minimum limits for a class

    - by Luis
    Basically what the title says... I have created a class that models time slots in a variable-granularity daily schedule (where for example the first time slot is 30 minutes, but the second time slot can be 40 minutes); the first available slot starts at (a value comparable to) 1. What I want to do now is to define somehow the maximum and minimum allowable values that this class takes and I have two practical questions in order to do so: 1.- does it make sense to define absolute minimum and maximum in such a way for a custom class? Or better, does it suffice that a value always compares as lower-than any other possible value of the type, given the class's defined relational operators, to be defined the min? (and analogusly for the max) 2.- assuming the previous question has an answer modeled after "yes" (or "yes but ..."), how do I define such max/min? I know that there is std::numeric_limits<> but from what I read it is intended for "numeric types". Do I interpret that as meaning "represented as a number" or can I make a broader assumption like "represented with numbers" or "having a correspondence to integers"? After all, it would make sense to define the minimum and maximum for a date class, and maybe for a dictionary class, but numeric_limits may not be intended for those uses (I don't have much experience with it). Plus, numeric_limits has a lot of extra members and information that I don't know what to make with. If I don't use numeric_limits, what other well-known / widely-used mechanism does C++ offer to indicate the available range of values for a class?

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  • jQuery each loop - using variables

    - by Sam
    I have a list of products. Each product has a title and a review link. Currently the titles link directly to the individual product page, and the review links go elsewhere. I'd like to use a jquery each loop to cycle through each li, take the href from the title (the first link), and apply it to the review link (the second link), so they both point to the product page. Simplified code would be as follows: <ul> <li><a href="product1.html">Product 1</a><a href="review1.html">Review 1</a></li> <li><a href="product2.html">Product 2</a><a href="review2.html">Review 2</a></li> <li><a href="product3.html">Product 3</a><a href="review3.html">Review 3</a></li> </ul> I thought it would be something like the following: $("li").each(function(){ var link = $("a:eq(0)").attr('href'); $("a:eq(1)").attr("href", link); }); But it always uses the same variable "link". Can someone help me out?

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  • Using the <h2> as the title after sent?

    - by Delan Azabani
    Currently, I have a semi-dynamic system for my website's pages. head.php has all the tags before the content body, foot.php the tags after. Any page using the main theme will include head.php, then write the content, then output foot.php. Currently, to be able to set the title, I quickly set a variable $title before inclusion: <?php $title = 'Untitled document'; include_once '../head.php'; ?> <h2>Untitled document</h2> Content here... <?php include_once '../foot.php'; ?> So that in head.php... <title><?php echo $title; ?> | Delan Azabani</title> However, this seems kludgy as the title is most of the time, the same as the content of the h2 tag. Is there a way I can get PHP to read the content of h2, track back and insert it, then send the whole thing at the end?

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  • Python: Does one of these examples waste more memory?

    - by orokusaki
    In a Django view function which uses manual transaction committing, I have: context = RequestContext(request, data) transaction.commit() return render_to_response('basic.html', data, context) # Returns a Django ``HttpResponse`` object which is similar to a dictionary. I think it is a better idea to do this: context = RequestContext(request, data) response = render_to_response('basic.html', data, context) transaction.commit() return response If the page isn't rendered correctly in the second version, the transaction is rolled back. This seems like the logical way of doing it albeit there won't likely be many exceptions at that point in the function when the application is in production. But... I fear that this might cost more and this will be replete through a number of functions since the application is heavy with custom transaction handling, so now is the time to figure out. If the HttpResponse instance is in memory already (at the point of render_to_response()), then what does another reference cost? When the function ends, doesn't the reference (response variable) go away so that when Django is done converting the HttpResponse into a string for output Python can immediately garbage collect it? Is there any reason I would want to use the first version (other than "It's 1 less line of code.")?

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  • Where is the errnos defined? Example linux c/c++ program for i2c.

    - by Johan
    Hi When something goes wrong in a classic linux c/c++ software we have the magic variable errno that gives us a clue on what just went wrong. But where is those errors defined? Let's take a example (it's actually a piece from a Qt app, therefore the qDebug()). if (ioctl(file, I2C_SLAVE, address) < 0) { int err = errno; qDebug() << __FILE__ << __FUNCTION__ << __LINE__ << "Can't set address:" << address << "Errno:" << err << strerror(err); .... The next step is to look at what that errno was so we can decide if we just quit or try to do something about the problem. So we maybe add a if or switch at this point. if (err == 9) { // do something... } else { //do someting else } And my question is where to find the errors that "9" represents? I don't like that kind of magic numbers in my code. /Thanks

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  • Can you catch exceeded allocated memory error before it kills the script?

    - by kristovaher
    The thing is that I want to catch memory problems before they happen. I have a system that gets rows from database and casts the returned associative array to a variable, but I never know what the size of the database result is is or how much memory it will take once the database request is made. This means that my software can fail simply because memory is exceeded. But I want to avoid that somehow. One of the ways is to obviously make database requests that are smaller, but what if this is not possible or what if I do not know the size of data that is returned from database? Is it possible to 'catch' situations where memory use is exceeded in PHP? Something like this: $requestOk=memory_test(function(){ return doSomething(); }); if($requestOk){ // Memory seems fine // $requestOk now has the value from memory_test() function } else { // Function would have exceeded memory } I just find it problematic that my script can just die at any moment because of memory issues. From what I know, try-catch cannot be used here because it is a fatal error. Any help would be appreciated!

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  • php request variables assigning $_GEt

    - by chris
    if you take a look at a previous question http://stackoverflow.com/questions/2690742/mod-rewrite-title-slugs-and-htaccess I am using the solution that Col. Shrapnel proposed- but when i assign values to $_GET in the actual file and not from a request the code doesnt work. It defaults away from the file as if the $_GET variables are not set The code I have come up with is- if(!empty($_GET['cat'])){ $_GET['target'] = "category"; if(isset($_GET['page'])){ $_GET['pageID'] = $_GET['page']; } $URL_query = "SELECT category_id FROM cats WHERE slug = '".$_GET['cat']."';"; $URL_result = mysql_query($URL_query); $URL_array = mysql_fetch_array($URL_result); $_GET['category_id'] = $URL_array['category_id']; }elseif($_GET['product']){ $_GET['target'] = "product"; $URL_query = "SELECT product_id FROM products WHERE slug = '".$_GET['product']."';"; $URL_result = mysql_query($URL_query); $URL_array = mysql_fetch_array($URL_result); print_r($URL_array); $_GET['product_id'] = $URL_array['product_id']; The original variable string that im trying to represent is /cart.php?Target=product&product_id=16142&category_id=249 And i'm trying to build the query string variables with code and including cart.php so i can use cleaner URL's So I have product/product-title-with-clean-url/ going to slug.php?product=slug Then the slug searches the db for a record with the matching slug and returns the product_id as in the code above.Then built the query string and include cart.php

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