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  • PHP error T_object_operator

    - by kwek-kwek
    I am getting this error : Parse error: syntax error, unexpected T_OBJECT_OPERATOR in wp-content/themes/phil/page.php on line 104 This is my code: <?php $todaysDate = date ('M d'); $event_query = new WP_Query('showposts=5&category_name=events&meta_key=Date&meta_compare=>=&meta_value='.$todaysDate.'&orderby=meta_value=order=ASC'); ?> <?php if (event_query->have_post()) : while ($event_query->have_post()) : $event_query->the_post(); $eventMeta = get_post_meta($post->ID, 'Date', true); $eventDate = strtotime($eventMeta); $displayDate = date ('M d', $eventDate); ?> <li> <span class="date"><?php echo $displayDate ; ?></span> <span><a href="<?php the_permalink();?>" title="<?php the_title(); ?>"><?php the_title(); ?></a></span></li> <?php endwhile; else:?> <li>No Upcoming events</li> <?php endif;?> I am pretty new to this PHP stuff and WOrdpress so let me know what am I doing wrong. or paste the code to replace. Thank you

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  • How to repair Java in Ubuntu after trying to switch to Java 6 using update-java-alternatives

    - by Kau-Boy
    I tried to switch from Java 5 to Java 6 using the "update-java-alternatives" command like explained on this page: https://help.ubuntu.com/community/Java But afterwards I get the following error when I tried to execute java: root@webserver:~# java Error occurred during initialization of VM Could not reserve enough space for object heap Could not create the Java virtual machine. I also tried to reinstall the java binaries using "apt-get" but I didn't succeed reinstalling it. I would like to post the "apt-get" errors, but unfortunately I don't know how to print out the error messages in English and not in German. My system is a Ubuntu 8.04 ROOT server. Here is the (Google translated) english text tring to install Java 6 again: root@server:~# apt-get install sun-java6-jdk Reading package lists ... Ready Dependency tree Reading state information ... Ready sun-java6-jdk is already the newest version. sun-java6-jdk set to manually installed. 0 upgraded, 0 newly installed, 0 to remove and 86 not upgraded. 1 not fully installed or removed. After this operation, 0B of additional disk space will be used. Set up a sun-java6-bin (6-03-0ubuntu2) ... Could not create the Java virtual machine. dpkg: error processing sun-java6-bin (- configure): Subprocess post-installation script returned error exit status 1 Errors were encountered while processing: sun-java6-bin E: Sub-process / usr / bin / dpkg returned an error code (1) I hope that this might help you helping me.

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  • Set JTabbedPane width to constant

    - by msp
    I'm implementing an UI in Java Swing. Therefore I use a JTabbedPane. The tabbedPane has no components at startup. When i add a tab to the tabbedpane, the width of the tabbedpane increases, when i remove the tab, the width resizes to the width at the startup. This should not happen. The tabbedpane is placed on a JPanel which has a gridbag layout. Layout code: Container contentPane = mainFrame.getContentPane(); contentPane.setLayout( new GridBagLayout() ); GridBagConstraints c = new GridBagConstraints(); // add the component tree initComponentTree(); c.gridx = 0; c.gridy = 0; c.gridheight = 1; c.gridwidth = 1; c.fill = GridBagConstraints.BOTH; c.anchor = GridBagConstraints.LINE_START; c.weightx = 1; c.weighty = 1; contentPane.add( componentTree, c ); // add the tabbed pane initTabbedPane(); c.gridx = 1; c.weightx = 10; contentPane.add( tabbedPane, c ); // add the status panel initStatusPanel(); c.gridx = 0; c.gridy = 1; c.gridwidth = 2; c.fill = GridBagConstraints.HORIZONTAL; c.anchor = GridBagConstraints.LINE_START; c.weightx = 0; c.weighty = 0; contentPane.add( statusPanel, c ); Hope someone can help!

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  • Bizzare Java invalid Assignment Operator Error

    - by Kay
    public class MaxHeap<T extends Comparable<T>> implements Heap<T>{ private T[] heap; private int lastIndex; private static final int defaultInitialCapacity = 25; public void add(T newItem) throws HeapException{ if (lastIndex < Max_Heap){ heap[lastIndex] = newItem; int place = lastIndex; int parent = (place – 1)/2; //ERROR HERE********** while ( (parent >=0) && (heap[place].compareTo(heap[parent])>0)){ T temp = heap[place]; heap[place] = heap[parent]; heap[parent] = temp; place = parent; parent = (place-1)/2; }else { throw new HeapException(“HeapException: Heap full”); } } } Eclipse complains that there is a: "Syntax error on token "Invalid Character", invalid AssignmentOperator" With the red line beneath the '(place-1)' There shouldn't be an error at all since it's just straight-forward arithmetic. Or is it not that simple?

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  • Best way to parse this particular string using awk / sed?

    - by Jack
    Hi, I need to get a particular version string from a file (call it version.lst) and use it to compare another in a shell script. For example sake, the file contains lines that look like this: V1.000 -- build date and other info here -- APP1 V1.000 -- build date and other info here -- APP2 V1.500 -- build date and other info here -- APP3 .. and so on. Let's say I am trying to grab the first version (in this case, V1.000) from APP1. Obviously, the versions can change and I want this to be dynamic. What I have right now works: var = `cat version.lst | grep " -- APP1" | grep -Eo V[0-9].[0-9]{3}` Pipe to grep will get the line containing APP1 and the second pipe to grep will get the version string. However, I hear grep is not the way to do this so I'd like to learn the best way using awk or sed. Any ideas? I am new to both and haven't found a tutorial easy enough to learn the syntax of it. Do they support egrep? Thanks!

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  • Communicating with a running python daemon

    - by hanksims
    I wrote a small Python application that runs as a daemon. It utilizes threading and queues. I'm looking for general approaches to altering this application so that I can communicate with it while it's running. Mostly I'd like to be able to monitor its health. In a nutshell, I'd like to be able to do something like this: python application.py start # launches the daemon Later, I'd like to be able to come along and do something like: python application.py check_queue_size # return info from the daemonized process To be clear, I don't have any problem implementing the Django-inspired syntax. What I don't have any idea how to do is to send signals to the daemonized process (start), or how to write the daemon to handle and respond to such signals. Like I said above, I'm looking for general approaches. The only one I can see right now is telling the daemon constantly log everything that might be needed to a file, but I hope there's a less messy way to go about it. UPDATE: Wow, a lot of great answers. Thanks so much. I think I'll look at both Pyro and the web.py/Werkzeug approaches, since Twisted is a little more than I want to bite off at this point. The next conceptual challenge, I suppose, is how to go about talking to my worker threads without hanging them up. Thanks again.

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  • casting char[][] to char** causes segfault?

    - by Earlz
    Ok my C is a bit rusty but I figured I'd make my next(small) project in C so I could polish back up on it and less than 20 lines in I already have a seg fault. This is my complete code: #define ROWS 4 #define COLS 4 char main_map[ROWS][COLS+1]={ "a.bb", "a.c.", "adc.", ".dc."}; void print_map(char** map){ int i; for(i=0;i<ROWS;i++){ puts(map[i]); //segfault here } } int main(){ print_map(main_map); //if I comment out this line it will work. puts(main_map[3]); return 0; } I am completely confused as to how this is causing a segfault. What is happening when casting from [][] to **!? That is the only warning I get. rushhour.c:23:3: warning: passing argument 1 of ‘print_map’ from incompatible pointer type rushhour.c:13:7: note: expected ‘char **’ but argument is of type ‘char (*)[5]’ Are [][] and ** really not compatible pointer types? They seem like they are just syntax to me.

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  • Are there any shortcuts/easier(VB) style way for raising events in C#?

    - by Eric
    Example in VB I have a worker class Public Class worker Public Event EventNumber1(ByVal messages As Dictionary(Of Integer, String)) Public Event EventNumber2(ByVal message As String) Public Sub CallEventNumber1() Dim dict As New Dictionary(Of Integer, String) dict.Add(1, "EventNumber1 First message") dict.Add(2, "EventNumber1 Second message") RaiseEvent EventNumber1(dict) End Sub Public Sub CallEventNumber2() RaiseEvent EventNumber2("I am an EventNumber2 Message") End Sub End Class and wire them up in another class with AddHandler _worker.EventNumber1, AddressOf EventNumber1Handler AddHandler _worker.EventNumber2, AddressOf EventNumber2Handler and in C# the worker class class Worker { public delegate void EventNumber1Handler(Dictionary<int, string> messages); public delegate void EventNumber2Handler(string message); public event EventNumber1Handler EventNumber1; public event EventNumber2Handler EventNumber2; public void CallEventNumber1() { Dictionary<int, string> dict = new Dictionary<int, string>(); dict.Add(1, "EventNumber1 First message"); dict.Add(2, "EventNumber1 Second message"); if (EventNumber1 != null) EventNumber1(dict); } public void CallEventNumber2() { if (EventNumber2 != null) EventNumber2("I am an EventNumber2 Message"); } } and wire that up with worker.EventNumber1 += new Worker.EventNumber1Handler(worker_EventNumber1); worker.EventNumber2 += new Worker.EventNumber2Handler(worker_EventNumber2); So I guess my question is do I always need to add the delegate along with the event in c#? Is there any new syntax for c# 3.0/4.0? Regards _Eric

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  • Unable to parse variable length string separated by delimiter

    - by Technext
    Hi, I have a problem with parsing a string, which consists only of directory path. For ex. My input string is Abc\Program Files\sample\ My output should be Abc//Program Files//sample The script should work for input path of any length i.e., it can contain any no. of subdirectories. (For ex., abc\temp\sample\folder\joe) I have looked for help in many links but to no avail. Looks like FOR command extracts only one whole line or a string (when we use ‘token’ keyword in FOR syntax) but my problem is that I am not aware of the input path length and hence, the no. of tokens. My idea was to use \ as a delimiter and then extract each word before and after it (), and put the words to an output file along with // till we reach the end of the string. I tried implementing the following but it did not work: @echo off FOR /F "delims=\" %%x in (orig.txt) do ( IF NOT %%x == "" echo.%%x//output.txt ) The file orig.txt contains only one line i.e, Abc\Program Files\sample\ The output that I get contains only: Abc// The above output contains blank spaces as well after ‘Abc//’ My desired output should be: Abc//program Files//sample// Can anyone please help me with this? Regards, Technext

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  • Input html tag not parsing properly in php

    - by Akaash
    I have a database with names that I would like displayed in the form of a table with checkboxes. Everything works until I try to place the html tag into my php code. When I put the input tag in it gives me the error: Parse error: syntax error, unexpected T_STRING, expecting ',' or ';' I can't see where I would put a comma or semi colon. <form> <?php $name = $_POST['name']; $host = "mysql16.000webhost.com"; $user_name = "a1611480_akaash"; $pwd = "****"; $database_name = "a1611480_akaash"; $db = mysql_connect($host, $user_name, $pwd); mysql_select_db($database_name); $result = mysql_query("SELECT name FROM Sort"); $var = array(); while ($row = mysql_fetch_array($result)) { $var[] = $row['name']; } $unique = array_unique($var); foreach ($unique as $value) { echo "<p class = Body_text><label>$value</label> <input type="checkbox" name="name" value="$value" /> </p>\n"; } ?> </form>

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  • Using jquery to change checkbox status

    - by Jeff
    Hi everyone! I have a list of items that have checkboxes associated with them, and the items are beneath a list header, which also has a checkbox(for db purposes only) which is actually hidden from view. I need to make it so that if any of the checkboxes beneath the header is checked, then the header checkbox is checked as well. BUT I also need to make it so that if all of the checkboxes are unchecked, then the header one is unchecked...how hard is this going to be? This is how I have it setup now: if($('.childCheckBox').is(":checked")){ $('#parentBox').attr('checked', true); } Now I am thinking that if I were to do something where I add an else if clause: else if($('.proBox2').is(not)(":checked"){ alert("uncheck parent"); } But I don't know the correct syntax for is-not, or isn't, or even if there is anything that will do that. Are there any thoughts out there? I need the box to check if one is selected and uncheck if none are selected. Thanks!!

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  • Meteor: how to update DOM via Javascript without a page refresh?

    - by strack
    UPDATE: It looks like this script may be the catalyst I'm looking for. Will test it and answer/close this question if so. I'm sure I'll find the answer to this eventually, but I'm putting it out there now, in case someone else knows it right off... I am using RaphaelJS to manipulate the DOM (adds a bunch of SVG tags to an identified DIV), and I want to re-render those specific DOM parts, if there's an update to the MongoDB collection. As an example: -Let's say that I have a collection called PiePieces. -When the page is first rendered/ called, let's pretend that the number of pieces in the collection is 4. -I programmatically add a pie piece using console: PiePieces.insert({...}) -I want the page to update like it would for a standard handlebars binding situation, but the problem is, the new entry needs to go through the Raphael script, which performs direct DOM manipulation. So, the logic would go something like this: MongoDB collection update event - Client function call to manipulate DOM - DOM modified/ page updated without a refresh. I've tried implementing this by reading values from the DOM itself, and I can get the updated DOM, but the entire page refreshes and/or I have to manually refresh the page, OR the DOM tree isn't completed yet, and so it's blank until I refresh. Can you point me in the right direction, maybe with a small code snippet/example? (if something similar already exists, just tell me where and I'll go digging) Thanks in advance! (I am LOVING Meteor so far...)

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  • XPath Query - Select relative top level nodes

    - by John
    I'm trying to iterate over some elements in an XML document that may be nested, but as I iterate over them I may be removing some from the tree. I'm thinking the best way is to do this recursively, so I'm trying to come up with an XPath Query that will select all the top-level nodes relative to the current node. //foo[not(ancestor::foo)] works great at the document level, but I'm trying to figure out how to do this from a relative query. <foo id="1"> <foo id="2" /> <foo id="3"> <foo id="4"> <bar> <foo id="5"> <foo id="6" /> </foo> <foo id="7" /> </bar> </foo> </foo> </foo> If the current node is foo#3, I only want to select foo#4. When the current node is foo#4, I only want to select foo#5 and foo#7. I think I'm trying to select any descendant foo nodes of the current node, but without any ancestor foo nodes between the current node and the node I'm selecting. My conundrum is if we're already inside a foo node, not(ancestor::foo) doesn't help.

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  • static member specialization of templated child class and templated base class

    - by b3nj1
    I'm trying to have a templated class (here C) that inherits from another templated class (here A) and perform static member specialization (of int var here), but I cant get the right syntax to do so (if it's possible #include <iostream> template<typename derived> class A { public: static int var; }; //This one works fine class B :public A<B> { public: B() { std::cout << var << std::endl; } }; template<> int A<B>::var = 9; //This one doesn't works template<typename type> class C :public A<C<type> > { public: C() { std::cout << var << std::endl; } }; //template<> template<typename type> int A<C<type> >::a = 10; int main() { B b; C<int> c; return 0; } I put an example that works with a non templated class (here B) and i can get the static member specialization of var, but for C that just doesn't work. Here is what gcc tells me : test.cpp: In constructor ‘C<type>::C()’: test.cpp:29:26: error: ‘var’ was not declared in this scope test.cpp: At global scope: test.cpp:34:18: error: template definition of non-template ‘int A<C<type> >::a’ I'm using gcc version 4.6.3, thanks for any help

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  • Is there a way to create subdatabases as a kind of subfolders in sql server?

    - by user193655
    I am creating an application where there is main DB and where other data is stored in secondary databases. The secondary databases follow a "plugin" approach. I use SQL Server. A simple installation of the application will just have the mainDB, while as an option one can activate more "plug-ins" and for every plug-in there will be a new database. Now why I made this choice is because I have to work with an exisiting legacy system and this is the smartest thing I could figure to implement the plugin system. MainDB and Plugins DB have exactly the same schema (basically Plugins DB have some "special content", some important data that one can use as a kind of template - think to a letter template for example - in the application). Plugin DBs are so used in readonly mode, they are "repository of content". The "smart" thing is that the main application can also be used by "plugin writers", they just write a DB inserting content, and by making a backup of the database they creaetd a potential plugin (this is why all DBs has the same schema). Those plugins DB are downloaded from internet as there is a content upgrade available, every time the full PlugIn DB is destroyed and a new one with the same name is creaetd. This is for simplicity and even because the size of this DBs is generally small. Now this works, anyway I would prefer to organize the DBs in a kind of Tree structure, so that I can force the PlugIn DBs to be "sub-DBs" of the main application DB. As a workaround I am thinking of using naming rules, like: ApplicationDB (for the main application DB) ApplicationDB_PlugIn_N (for the N-th plugin DB) When I search for plugin 1 I try to connect to ApplicationDB_PlugIn_1, if I don't find the DB i raise an error. This situation can happen for example if som DBA renamed ApplicationDB_Plugin_1. So since those Plugin DBs are really dependant on ApplicationDB only I was trying to "do the subfolder trick". Can anyone suggest a way to do this? Can you comment on this self-made plugin approach I decribed above?

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  • How can I pass a hash to a Perl subroutine?

    - by Vishalrix
    In one of my main( or primary) routines,I have two or more hashes. I want the subroutine foo() to recieve these possibly-multiple hashes as distinct hashes. Right now I have no preference if they go by value, or as references. I am struggling with this for the last many hours and would appreciate help, so that I dont have to leave perl for php! ( I am using mod_perl, or will be) Right now I have got some answer to my requirement, shown here From http://forums.gentoo.org/viewtopic-t-803720-start-0.html # sub: dump the hash values with the keys '1' and '3' sub dumpvals { foreach $h (@_) { print "1: $h->{1} 3: $h->{3}\n"; } } # initialize an array of anonymous hash references @arr = ({1,2,3,4}, {1,7,3,8}); # create a new hash and add the reference to the array $t{1} = 5; $t{3} = 6; push @arr, \%t; # call the sub dumpvals(@arr); I only want to extend it so that in dumpvals I could do something like this: foreach my %k ( keys @_[0]) { # use $k and @_[0], and others } The syntax is wrong, but I suppose you can tell that I am trying to get the keys of the first hash ( hash1 or h1), and iterate over them. How to do it in the latter code snippet above?

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  • Make conversion to a native type explicit in C++

    - by Tal Pressman
    I'm trying to write a class that implements 64-bit ints for a compiler that doesn't support long long, to be used in existing code. Basically, I should be able to have a typedef somewhere that selects whether I want to use long long or my class, and everything else should compile and work. So, I obviously need conversion constructors from int, long, etc., and the respective conversion operators (casts) to those types. This seems to cause errors with arithmetic operators. With native types, the compiler "knows" that when operator*(int, char) is called, it should promote the char to int and call operator*(int, int) (rather than casting the int to char, for example). In my case it gets confused between the various built-in operators and the ones I created. It seems to me like if I could flag the conversion operators as explicit somehow, that it would solve the issue, but as far as I can tell the explicit keyword is only for constructors (and I can't make constructors for built-in types). So is there any way of marking the casts as explicit? Or am I barking up the wrong tree here and there's another way of solving this? Or maybe I'm just doing something else wrong...

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  • Add Hover display for table cell

    - by Jake
    I have a table, but it is not in a list format, meaning not a column/row format. I look for specific cells to add a hover event that displays a description of the cell. $("#TableID td").hover(function(){ //ifCellThatIWant $(this).append("<span>Message that was brought in</span>"); }, function(){ $(this).children().remove(); }); The problem is right now is that the hover displays a span(with info. inside) that I used jquery to append the span to the cell when mouseover, which expands the cell, which is an effect that I don't like or want. I'm Trying to have an out of the table look,but still be by the cell that triggered the event; because if the span has a lot of info. in it, expanding the cell dynamically will start to look pretty nasty. Also will help if I had some type of css direction on how will I make the display for the mouseover "description" span look nice. My mind thought is that a way to accomplish what I want is giver the appended span the position of my mouse cursor when hover, but not sure if its the right approach or what the syntax would look like.

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  • Java scripts conflict on my home page

    - by naveen
    <script type="text/javascript" src="jquery-1.js"></script> <script type="text/javascript" src="mootools.js"></script> <script type="text/javascript" src="slideshow.js"></script> <script type="text/javascript"> //<![CDATA[ window.addEvent('domready', function(){ var data = { '1.jpg': { caption: 'Volcano Asención in Ometepe, Nicaragua.' }, '2.jpg': { caption: 'A Ceibu tree.' }, '3.jpg': { caption: 'The view from Volcano Maderas.' }, '4.jpg': { caption: 'Beer and ice cream.' } }; var myShow = new Slideshow('show', data, {controller: true, height: 400, hu: 'images/', thumbnails: true, width: 500}); }); //]]> </script> <script type="text/javascript"> $(document).ready(function() { //slides the element with class "menu_body" when paragraph with class "menu_head" is clicked $("#firstpane p.menu_head").click(function() { $(this).css({backgroundImage:"url(down.png)"}).next("div.menu_body").slideToggle(300).siblings("div.menu_body").slideUp("slow"); $(this).siblings().css({backgroundImage:"url(left.png)"}); }); //slides the element with class "menu_body" when mouse is over the paragraph $("#secondpane p.menu_head").mouseover(function() { $(this).css({backgroundImage:"url(down.png)"}).next("div.menu_body").slideDown(500).siblings("div.menu_body").slideUp("slow"); $(this).siblings().css({backgroundImage:"url(left.png)"}); }); }); </script> <!--[if lt IE 7]> <script type="text/javascript" src="unitpngfix.js"></script> <![endif]-->

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  • MySQL Update query with left join and group by

    - by Rob
    I am trying to create an update query and making little progress in getting the right syntax. The following query is working: SELECT t.Index1, t.Index2, COUNT( m.EventType ) FROM Table t LEFT JOIN MEvents m ON (m.Index1 = t.Index1 AND m.Index2 = t.Index2 AND (m.EventType = 'A' OR m.EventType = 'B') ) WHERE (t.SpecialEventCount IS NULL) GROUP BY t.Index1, t.Index2 It creates a list of triplets Index1,Index2,EventCounts. It only does this for case where t.SpecialEventCount is NULL. The update query I am trying to write should set this SpecialEventCount to that count, i.e. COUNT(m.EventType) in the query above. This number could be 0 or any positive number (hence the left join). Index1 and Index2 together are unique in Table t and they are used to identify events in MEvent. How do I have to modify the select query to become an update query? I.e. something like UPDATE Table SET SpecialEventCount=COUNT(m.EventType)..... but I am confused what to put where and have failed with numerous different guesses.

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  • C# Linq Select Problem in Method Chain.

    - by Gnought
    Note that the _src inherit IQueryable<U> and V inherit new(); I wrote the following statement, there is no syntax error. IQueryable<V> a = from s in _src where (s.Right - 1 == s.Left) select new V(); But if i re-wrote it as follows, the Visual Studio editor complains an error in the "Select" IQueryable<V> d = _src.Where(s => s.Right - 1 == s.Left).Select(s=> new V()); The Error is: The type arguments cannot be inferred from the usage. Try specifying the type arguments explicitly. Candidates are: System.Collections.Generic.IEnumerable<V> Select<U,V>(this System.Collections.Generic.IEnumerable<U>, System.Func<U,V>) (in class Enumerable) System.Linq.IQueryable<V> Select<U,V>(this System.Linq.IQueryable<U>, System.Linq.Expressions.Expression<System.Func<U,V>>) (in class Queryable) Could anyone explain this phenomenon, and what the solution is to fix the error?

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  • How to run a javascript function before postback of asp.net button?

    - by Curtis White
    I'm using Javascript to create a DIV element and open up a new page by using onclientclick. This works great. Now, I need to write to it from the server side and this element must be created before it is posted back. How do I get the javascript to execute before the postback? Currently, I have to press the button twice because the element doesn't exist to write too on the first click. To be clear, I need this to execute before the "OnClick" of the button. Update: It looks like the Javascript function is called before the postback but the element is not updated until I run the second postback. Hmm Update: Unfortunately it is a bit more complicated then this. I'm creating a div tag in javascript to open a new window. Inside the div tag, I'm using a databinding syntax <%=Preview% so that I can get access to this element on the server side. From the server side, I'm injecting the code. I'm thinking this may be a chicken-egg problem but not sure. UPDATE! It is not the Javascript not running first. It is the databinding mechanism which is reading the blank variable before I'm able to set it. Hmm

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  • Does using functional languages help against computing values repeatedly?

    - by sharptooth
    Consider a function f(x,y): f(x,0) = x*x; f(0,y) = y*(y + 1); f(x,y) = f(x,y-1) + f(x-1,y); If one tries to implement that recursively in some language like C++ he will encounter a problem. Suppose the function is first called with x = x0 and y = y0. Then for any pair (x,y) where 0 <= x < x0 and 0 <= y < y0 the intermediate values will be computed multiple times - recursive calls will form a huge tree in which multiple leaves will in fact contain the same pairs (x,y). For pairs (x,y) where x and y are both close to 0 values will be computed numerous times. For instance, I tested a similar function implemented in C++ - for x=20 and y=20 its computation takes about 4 hours (yes, four Earth hours!). Obviously the implementation can be rewritten in such way that repeated computation doesn't occur - either iteratively or with a cache table. The question is: will functional languages perform any better and avoid repeated computations when implementing a function like above recursively?

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  • Return multiple IDs from a function and use the result in a query

    - by NewK
    I have this function that returns me all children of a tree node: CREATE OR REPLACE FUNCTION fn_category_get_childs_v2(id_pai integer) RETURNS integer[] AS $BODY$ DECLARE ids_filhos integer array; BEGIN SELECT array ( SELECT category_id FROM category WHERE category_id IN ( (WITH RECURSIVE parent AS ( SELECT category_id , parent_id from category WHERE category_id = id_pai UNION ALL SELECT t.category_id , t.parent_id FROM parent INNER JOIN category t ON parent.category_id = t.parent_id ) SELECT category_id FROM parent WHERE category_id <> id_pai ) ) ) into ids_filhos; return ids_filhos; END; and I would like to use it in a select statement like this: select * from teste1_elements where category_id in (select * from fn_category_get_childs_v2(12)) I've also tried this way with the same result: select * from teste1_elements where category_id=any(select * from fn_category_get_childs_v2(12))) But I get the following error: ERROR: operator does not exist: integer = integer[] LINE 1: select * from teste1_elements where category_id in (select *... ^ HINT: No operator matches the given name and argument type(s). You might need to add explicit type casts. The function returns an integer array, is that the problem? SELECT * from fn_category_get_childs_v2(12) retrieves the following array (integer[]): '{30,32,34,20,19,18,17,16,15,14}'

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  • How combine TabBar + Navigation with XCode

    - by mamcx
    I'm triying to combine a TabBar + Navigation app. I have 5 tab bars, 4 are listing of stuff and drill down to details views. I try to follow this tutorial: http://www.iphonedevforums.com/forum/iphone-sdk-development/124-view-controller-problem.html But always get a blank view. This is what I do, with a clean project: I start with a TabBar template app. I put 5 tab bar buttons. I create a controller like: @interface FirstViewController : UINavigationController { } I put the main window.xib on tree mode & change the selected first view to FirstViewController I select the TabBar Controller in Interface builder, go to TabBar Attributes & change the class to navigation controler. Select the fist view & put the nib name "SecondView" In response, I get a blank screen. I must add that I wanna navigate from the details views, no from the main windows. i.e in the main window tab bar 1 is the list of people. I select a person then wanna navigate to the detail window.

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