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  • Subroutine & GoTo design

    - by sub
    I have a strange question concerning subroutines: As I'm creating a minimal language and I don't want to add high-level loops like while or for I was planning on just adding gotos to keep it Turing-Complete. Now I thought, eww - gotos - I wouldn't want to program in that language if I had to use gotos so often. So I thought about adding subroutines instead. I see the difference as the following: gotos Go to (captain obvious) a previously defined point and continue executing the program from there. Leads to hardly understandable and buggy code, I think that's a fact. subroutines Similiar: You define their starting point somewhere, as you call them the program jumps there - but the subroutine can go back to the point it was called from with return. Okay. Why didn't I just add the more function-like, nice looking subroutines? Because: In order to make return work if I call subroutines from within subroutines from within other subroutines, I'd have to use a stack containing the point where the currently running subroutine came from at top. That would then mean that I would, if I create loops using the subroutines, end up with an extremely memory-eating, overflowing stack with return locations. Not good. Don't think of my subroutines as functions. They are just gotos that return to the point they were called from, they don't actually give back values like the return x; statement in nearly all today's languages. Now to my actual questions: How can I solve the above problem with the stack overflow on loops with subroutines? Do I have to add a separate goto language construct without the return option? Assembler doesn't have loops but as I have seen myJumpPoint:, jnz, jz, retn. That means to me that there must also be a stack containing all the return locations. Am I right with that? What about long running loops then? Don't they overflow the stack/eat memory then? Am I getting the retn symbol in assembler totally wrong? If yes, please explain it to me.

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  • showing errors from actions in table-based views

    - by enashnash
    I have a view where I want to perform different actions on the items in each row in a table, similar to this (in, say, ~/Views/Thing/Manage.aspx): <table> <% foreach (thing in Model) { %> <tr> <td><%: thing.x %></td> <td> <% using (Html.BeginForm("SetEnabled", "Thing")) { %> <%: Html.Hidden("x", thing.x) %> <%: Html.Hidden("enable", !thing.Enabled) %> <input type="submit" value="<%: thing.Enabled ? "Disable" : "Enable" %>" /> <% } %> </td> <!-- more tds with similar action forms here, a few per table row --> </tr> <% } %> In my ThingController, I have functions similar to the following: public ActionResult Manage() { return View(ThingService.GetThings()); } [HttpPost] public ActionResult SetEnabled(string x, bool enable) { try { ThingService.SetEnabled(x, enable); } catch (Exception ex) { ModelState.AddModelError("", ex.Message); // I know this is wrong... } return RedirectToAction("Manage"); } In the most part, this is working fine. The problem is that if ThingService.SetEnabled throws an error, I want to be able to display the error at the top of the table. I've tried a few things with Html.ValidationSummary() in the page but I can't get it to work. Note that I don't want to send the user to a separate page to do this, and I'm trying to do it without using any javascript. Am I going about displaying my table in the best way? How do I get the errors displayed in the way I want them to? I will end up with perhaps 40 small forms on the page. This approach comes largely from this article, but it doesn't handle the errors in the way I need to. Any takers?

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  • WCF Duplex Interaction with Web Server

    - by Mark Struzinski
    Here is my scenario, and it is causing us a considerable amount of grief at the moment: We have a vendor web service which provides base level telephony functionality. This service has a SOAP api, which we are leveraging to build up a custom UI that is integrated into our in house web apps. The api functions on 2 levels. You make standard client calls into the service to initiate actions, such as Login, Place Call, Hang Up, etc. On a different thread, the service sends events back to the client to alert the user of things that are occurring on the system (agent successfully logged in, call was disconnected, etc). I implemented a WCF service to sit between the web server and the vendor service. This WCF service operates in duplex mode, establishing a 2 way connection with the web server. The web server makes outbound calls to the WCF service, which routes them to the vendor's web service. Events are received back to the WCF service, which passes them onto the web server via a callback channel on the WCF client. As events are received on the web server, they are placed into a hash table with the user's name as the key, and a .NET queue as the value to hold the event. Each event is enqueued to the agent who owns it. On a 2 second interval, the web page polls the web server via an ajax request to get new events for the logged in user. It hits the hash table for the user key, dequeues any events that are present, and serializes them back up to the web page. From there, they are processed in order and appropriate messages are displayed to the user. This implementation performs well in a single user scenario. The second I put more than 1 user on the system, I start getting frequent timeouts with the following CommunicationException: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond We are running Windows Server 2008 R2 both servers. Both the web app and WCF service are running on .NET 3.5. The WCF service is running under the net.tcp protocol in duplex mode. The web app is ASP.NET MVC 2. Has anyone dealt with anything like this scenario? Is there a more efficient way (or a widely accepted pattern) to implement this?

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  • How can I get image data from QTKit without color or gamma correction in Snow Leopard?

    - by Nick Haddad
    Since Snow Leopard, QTKit is now returning color corrected image data from functions like QTMovies frameImageAtTime:withAttributes:error:. Given an uncompressed AVI file, the same image data is displayed with larger pixel values in Snow Leopard vs. Leopard. Currently I'm using frameImageAtTime to get an NSImage, then ask for the tiffRepresentation of that image. After doing this, pixel values are slightly higher in Snow Leopard. For example, a file with the following pixel value in Leopard: [0 180 0] Now has a pixel value like: [0 192 0] Is there any way to ask a QTMovie for video frames that are not color corrected? Should I be asking for a CGImageRef, CIImage, or CVPixelBufferRef instead? Is there a way to disable color correction altogether prior to reading in the video files? I've attempted to work around this issue by drawing into a NSBitmapImageRep with the NSCalibratedColroSpace, but that only gets my part of the way there: // Create a movie NSDictionary *dict = [NSDictionary dictionaryWithObjectsAndKeys : nsFileName, QTMovieFileNameAttribute, [NSNumber numberWithBool:NO], QTMovieOpenAsyncOKAttribute, [NSNumber numberWithBool:NO], QTMovieLoopsAttribute, [NSNumber numberWithBool:NO], QTMovieLoopsBackAndForthAttribute, (id)nil]; _theMovie = [[QTMovie alloc] initWithAttributes:dict error:&error]; // .... NSMutableDictionary *imageAttributes = [NSMutableDictionary dictionary]; [imageAttributes setObject:QTMovieFrameImageTypeNSImage forKey:QTMovieFrameImageType]; [imageAttributes setObject:[NSArray arrayWithObject:@"NSBitmapImageRep"] forKey: QTMovieFrameImageRepresentationsType]; [imageAttributes setObject:[NSNumber numberWithBool:YES] forKey:QTMovieFrameImageHighQuality]; NSError* err = nil; NSImage* image = (NSImage*)[_theMovie frameImageAtTime:frameTime withAttributes:imageAttributes error:&err]; // copy NSImage into an NSBitmapImageRep (Objective-C) NSBitmapImageRep* bitmap = [[image representations] objectAtIndex:0]; // Draw into a colorspace we know about NSBitmapImageRep *bitmapWhoseFormatIKnow = [[NSBitmapImageRep alloc] initWithBitmapDataPlanes:NULL pixelsWide:getWidth() pixelsHigh:getHeight() bitsPerSample:8 samplesPerPixel:4 hasAlpha:YES isPlanar:NO colorSpaceName:NSCalibratedRGBColorSpace bitmapFormat:0 bytesPerRow:(getWidth() * 4) bitsPerPixel:32]; [NSGraphicsContext saveGraphicsState]; [NSGraphicsContext setCurrentContext:[NSGraphicsContext graphicsContextWithBitmapImageRep:bitmapWhoseFormatIKnow]]; [bitmap draw]; [NSGraphicsContext restoreGraphicsState]; This does convert back to a 'Non color corrected' colorspace, but the color values NOT are exactly the same as what is stored in the Uncompressed AVI files we are testing with. Also this is much less efficient because it is converting from RGB - "Device RGB" - RGB. Also, I am working in a 64-bit application, so dropping down to the Quicktime-C API is not an option. Thanks for your help.

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  • DOM Elements with same id and jQuery

    - by Steve
    Hi I have multiple elements with the same structure in my application. Second div element's id varies as per the comment id in the db which is unique. There are elements with the id 'vote_up' and 'vote_down'. This gets repeated for each comment.What happens is that, as I mentioned, there are multiple comments. I want to perform an Ajax request. First of this structure functions properly using ajax, but the rest does an http request. Btw I am developing a rails application and I am using jQuery. <div id="post_comment"> john<i> says </i> Comment<br/> <div id="comment_10_div"> **<form action="/comments/vote_up" id="vote_up" method="post">** <div style="margin:0;padding:0;display:inline"> <input name="authenticity_token" type="hidden" value="w873BgYHLxQmadUalzMRUC+1ql4AtP3U7f78dT8x9ho=" /> </div> <input id="Comment_place_id" name="Comment[post_id]" type="hidden" value="3" /> <input id="Comment_id" name="Comment[id]" type="hidden" value="10" /> <input id="Comment_user_id" name="Comment[user_id]" type="hidden" value="2" /> <input name="commit" type="submit" value="Vote up" /> </form> <label id="comment_10">10</label> **<form action="/comments/vote_down" id="vote_down" method="post">** <div style="margin:0;padding:0;display:inline"> <input name="authenticity_token" type="hidden" value="w873BgYHLxQmadUalzMRUC+1ql4AtP3U7f78dT8x9ho=" /> </div> <input id="Comment_place_id" name="Comment[place_id]" type="hidden" value="3" /> <input id="Comment_id" name="Comment[id]" type="hidden" value="10" /> <input id="Comment_user_id" name="Comment[user_id]" type="hidden" value="2" /> <input name="commit" type="submit" value="Vote Down" /> </form> </div> Can you please help me to solve this Thanks

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  • _heapwalk reports _HEAPBADNODE, causes breakpoint or loops endlessly

    - by Stefan Hubert
    I use _heapwalk to gather statistics about the Process' standard heap. Under certain circumstances i observe unexpected behaviours like: _HEAPBADNODE is returned some breakpoint is triggered inside _heapwalk, telling me the heap might got corrupted access violation inside _heapWalk. I saw different behaviours on different Computers. On one Windows XP 32 bit machine everything looked fine, whereas on two Windows XP 64 bit machines i saw the mentioned symptoms. I saw this behaviour only if LowFragmentationHeap was enabled. I played around a bit. I walked the heap several times right one after another inside my program. First time doing nothing in between the subsequent calls to _heapWalk (everything fine). Then again, this time doing some stuff (for gathering statistics) in between two subsequent calls to _heapWalk. Depending upon what I did there, I sometimes got the described symptoms. Here finally a question: What exactly is safe and what is not safe to do in between two subsequent calls to _heapWalk during a complete heap walk run? Naturally, i shall not manipulate the heap. Therefore i doublechecked that i don't call new and delete. However, my observation is that function calls with some parameter passing causes my heap walk run to fail already. I subsequently added function calls and increasing number of parameters passed to these. My feeling was two function calls with two paramters being passed did not work anymore. However I would like to know why. Any ideas why this does not happen on some machines? Any ideas why this only happens if LowFragmentationHeap is enabled? Sample Code finally: #include <malloc.h> void staticMethodB( int a, int b ) { } void staticMethodA( int a, int b, int c) { staticMethodB( 3, 6); return; } ... _HEAPINFO hinfo; hinfo._pentry = NULL; while( ( heapstatus = _heapwalk( &hinfo ) ) == _HEAPOK ) { //doing nothing here works fine //however if i call functions here with parameters, this causes //_HEAPBADNODE or something else staticMethodA( 3,4,5); } switch( heapstatus ) { ... case _HEAPBADNODE: assert( false ); /*ERROR - bad node in heap */ break; ...

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  • Referencing both an old version and new version of the same DLL (VB.Net)

    - by ckittel
    Consider the following situation: WidgetCompany produced a .NET DLL in 2006 called Widget.dll, version 1.0. I consumed this Widget.dll file throughout my VB.Net application. Over time, WidgetCompany has been updating Widget.dll, I never bothered to keep up, continuing to ship version 1.0 of Widget.dll with my software. It's now 2010, my project is now a VB.Net 3.5 application and WidgetCompany has come out with Widget.dll version 3.0. It looks and functions almost identical to Widget.dll version 1.0, using all the same namespaces and type names from before. However, Widget.dll version 3.0 has many run-time breaking changes since 1.0 and I cannot simply cut over to the new version; however, I don't want to continue developing against the 1.0 version and therefore keep digging myself deeper in the hole. What I want to do is do all new development in my project with Widget.dll version 3.0, whilst keeping Widget.dll version 1.0 around until I find time to convert all of my 1.0 consumption to the newer 3.0 code. Now, for starters, I obviously cannot simply reference both Widget.dll (Ver 1.0) and Widget.dll (Ver 3.0) in Visual Studio. Doing so gives me the following message: "A reference to 'Widget.dll' could not be added. A reference to the component 'Widget' already exists in the project." To work around that, I can simply rename version 3.0 Widget.dll to Widget.3.dll. But this is where I'm stuck. Any attempts to reference types found in "the dll" leads to ambiguity and the compiler obviously doesn't have any clue as to what I really want in this or that case. Is there something I can do that gives a DLL a new "root" Namespace or something? For example, if I could say "Widget.dll has a new root namespace of Legacy" then I could update existing code to reference the types found in Legacy.<RootNamespace> namespace while all new code could simply reference types from the <RootNamespace> namespace. Pipe dream or reality? Are there other solutions to situations this (besides "don't get in this situation in the first place")?

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  • How to develop asp.net web service to create the web method which can take the parameter of type win

    - by Shailesh Jaiswal
    I am developing asp.net web service. I am developing this web service so that OPC ( OLE for process control) client application can use it. In this web service I am using the built-in functions provided by the namespaces using OPC, using OPCDA, using OPCDA.NET. I have also added the namespace using System.Windows.Forms in this web service so that I can use the windows form control. In that we service I have created on web method which takes the parameter of type windows form control as given below. public void getOPCServerItems(TreeView tvServerItems, ListView lvBranchItems) { ArrayList ArrlstObj = new ArrayList(); ItemShowTreeList = OpcSrv.ShowBrowseTreeList(tvServerItems, lvBranchItems); ItemShowTreeList.BrowseModeOneLevel = true; // browse hierachy levels when selected. (default) ItemShowTreeList.Show(OpcSrv.ServerName); } In the above web method I need to pass the values to the built-in function ShowBrowseTreeList() (found in OPC, OPCDA, OPCDA.NET namespaces). This function takes the two parameter of windows form control type. These parameters are Treeview & ListView control of the windows form. In the above web method ShowBrowseTreeList() method automatically create the treeview & listview structure of the available items. Now as I am consuming the web service so I need to pass the values to the webmethod getOPCServerItems(). But as I my consuming application is asp.net application there is no such windows form control. In asp.net application there are also & control. I want to display The data returned in these asp.net controls rather than windows form control. I am not getting the way what should I need to do or how should I pass the values form my client application to this web service ? In the above method getOPCServerItems() when I use the parameter of type treeview & listview it generate s error "Cannot serialize member System.ComponentModel.Component.Site of type System.ComponentModel.ISite because it is an interface.". Can you provide me the the way In which I can write the above web method & how should I pass parameter to the Treeview & Listview control (windows form control) from my asp.net application ? which controls I should use to pass parameters ? Is there any need to do any type of casting ? Can you provide me the the code for above web method so that I can resolve the above issue ?

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  • Rtti accessing fields and properties in complex data structures

    - by Coco
    As already discussed in Rtti data manipulation and consistency in Delphi 2010 a consistency between the original data and rtti values can be reached by accessing members by using a pair of TRttiField and an instance pointer. This would be very easy in case of a simple class with only basic member types (like e.g. integers or strings). But what if we have structured field types? Here is an example: TIntArray = array [0..1] of Integer; TPointArray = array [0..1] of Point; TExampleClass = class private FPoint : TPoint; FAnotherClass : TAnotherClass; FIntArray : TIntArray; FPointArray : TPointArray; public property Point : TPoint read FPoint write FPoint; //.... and so on end; For an easy access of Members I want to buil a tree of member-nodes, which provides an interface for getting and setting values, getting attributes, serializing/deserializing values and so on. TMemberNode = class private FMember : TRttiMember; FParent : TMemberNode; FInstance : Pointer; public property Value : TValue read GetValue write SetValue; //uses FInstance end; So the most important thing is getting/setting the values, which is done - as stated before - by using the GetValue and SetValue functions of TRttiField. So what is the Instance for FPoint members? Let's say Parent is the Node for TExample class, where the instance is known and the member is a field, then Instance would be: FInstance := Pointer (Integer (Parent.Instance) + TRttiField (FMember).Offset); But what if I want to know the Instance for a record property? There is no offset in this case. So is there a better solution to get a pointer to the data? For the FAnotherClass member, the Instance would be: FInstance := Parent.Value.AsObject; So far the solution works, and data manipulation can be done by using rtti or the original types, without losing information. But things get harder, when working with arrays. Especially the second array of Points. How can I get the instance for the members of points in this case?

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  • [How-to] Make a working xml file in php (encoding properly) to export data from online database to i

    - by gotye
    Hey guys, I am trying to make an xml file to export my data from my database to my iphone. Each time I create a new post, I need to execute a php file to create a xml file containing the latest post ;) Okay so far ? :D Here is current php code ... but my nsxmlparser gives me an error code (33 - String is not started). I have no idea what kind of php functions I have to use ... <?php // Èdition du dÈbut du fichier XML $xml .= '<?xml version=\"1.0\" encoding=\"UTF-8\"?>'; $sml .= '<channel>'; $xml .= '<title>Infonul</title>'; $xml .= '<link>aaa</link>'; $xml .= '<description>aaa</description>'; // connexion a la base (mettre ‡ jour le mdp) $connect = mysql_connect('...-12','...','...'); /* selection de la base de donnÈe mysql */ mysql_select_db('...'); // selection des 20 derniËres news $res=mysql_query("SELECT u.display_name as author,p.post_date as date,p.comment_count as commentCount, p.post_content as content,p.post_title as title FROM wp_posts p, wp_users u WHERE p.post_status = 'publish' and p.post_type = 'post' and p.post_author = u.id ORDER BY p.id DESC LIMIT 0,20"); // extraction des informations et ajout au contenu while($tab=mysql_fetch_array($res)){ $title=$tab[title]; $author=$tab[author]; $content=$tab[content]; //html stuff $commentCount=$tab[commentCount]; $date=$tab[date]; $xml .= '<item>'; $xml .= '<title>'.$title.'</title>'; $xml .= '<content><![CDATA['.$content.']]></content>'; $xml .= '<date>'.$date.'</date>'; $xml .= '<author>'.$author.'</author>'; $xml .= '<commentCount>'.$commentCount.'</commentCount>'; $xml .= '</item>'; } // Èdition de la fin du fichier XML $xml .= '</channel>'; $xml = utf8_encode($xml); echo $xml; // Ècriture dans le fichier if ($fp = fopen("20news.xml",'w')) { fputs($fp,$xml); fclose($fp); } //mysql_close(); ?> I noticed a few things when i open 20news.xml in my browser : I got squares instead of single quotes ... I can't see <[CDATA[ but ]] is clearly visible ... why ?!? Thanks for any input ;) Gotye.

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  • Drupal 7: File field causes error with Dependable Dropdowns

    - by LoneWolfPR
    I'm building a Form in a module using the Form API. I've had a couple of dependent dropdowns that have been working just fine. The code is as follows: $types = db_query('SELECT * FROM {touchpoints_metric_types}') -> fetchAllKeyed(0, 1); $types = array('0' => '- Select -') + $types; $selectedType = isset($form_state['values']['metrictype']) ? $form_state['values']['metrictype'] : 0; $methods = _get_methods($selectedType); $selectedMethod = isset($form_state['values']['measurementmethod']) ? $form_state['values']['measurementmethod'] : 0; $form['metrictype'] = array( '#type' => 'select', '#title' => t('Metric Type'), '#options' => $types, '#default_value' => $selectedType, '#ajax' => array( 'event' => 'change', 'wrapper' => 'method-wrapper', 'callback' => 'touchpoints_method_callback' ) ); $form['measurementmethod'] = array( '#type' => 'select', '#title' => t('Measurement Method'), '#prefix' => '<div id="method-wrapper">', '#suffix' => '</div>', '#options' => $methods, '#default_value' => $selectedMethod, ); Here are the _get_methods and touchpoints_method_callback functions: function _get_methods($selected) { if ($selected) { $methods = db_query("SELECT * FROM {touchpoints_m_methods} WHERE mt_id=$selected") -> fetchAllKeyed(0, 2); } else { $methods = array(); } $methods = array('0' => "- Select -") + $methods; return $methods; } function touchpoints_method_callback($form, &$form_state) { return $form['measurementmethod']; } This all worked fine until I added a file field to the form. Here is the code I used for that: $form['metricfile'] = array( '#type' => 'file', '#title' => 'Attach a File', ); Now that the file is added if I change the first dropdown it hangs with the 'Please wait' message next to it without ever loading the contents of the second dropdown. I also get the following error in my JavaScript console: "Uncaught TypeError: Object function (a,b){return new p.fn.init(a,b,c)} has no method 'handleError'" What am I doing wrong here?

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  • architecture python question

    - by tom smith
    hi. creating a distributed crawling python app. it consists of a master server, and associated client apps that will run on client servers. the purpose of the client app is to run across a targeted site, to extract specific data. the clients need to go "deep" within the site, behind multiple levels of forms, so each client is specifically geared towards a given site. each client app looks something like main: parse initial url call function level1 (data1) function level1 (data) parse the url, for data1 use the required xpath to get the dom elements call the next function call level2 (data) function level2 (data2) parse the url, for data2 use the required xpath to get the dom elements call the next function call level3 function level3 (dat3) parse the url, for data3 use the required xpath to get the dom elements call the next function call level4 function level4 (data) parse the url, for data4 use the required xpath to get the dom elements at the final function.. --all the data output, and eventually returned to the server --at this point the data has elements from each function... my question: given that the number of calls that is made to the child function by the current function varies, i'm trying to figure out the best approach. each function essentialy fetches a page of content, and then parses the page using a number of different XPath expressions, combined with different regex expressions depending on the site/page. if i run a client on a single box, as a sequential process, it'll take awhile, but the load on the box is rather small. i've thought of attempting to implement the child functions as threads from the current function, but that could be a nightmare, as well as quickly bring the "box" to its knees! i've thought of breaking the app up in a manner that would allow the master to essentially pass packets to the client boxes, in a way to allow each client/function to be run directly from the master. this process requires a bit of rewrite, but it has a number of advantages. a bunch of redundancy, and speed. it would detect if a section of the process was crashing and restart from that point. but not sure if it would be any faster... i'm writing the parsing scripts in python.. so... any thoughts/comments would be appreciated... i can get into a great deal more detail, but didn't want to bore anyone!! thanks! tom

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  • How does MySQL's ORDER BY RAND() work?

    - by Eugene
    Hi, I've been doing some research and testing on how to do fast random selection in MySQL. In the process I've faced some unexpected results and now I am not fully sure I know how ORDER BY RAND() really works. I always thought that when you do ORDER BY RAND() on the table, MySQL adds a new column to the table which is filled with random values, then it sorts data by that column and then e.g. you take the above value which got there randomly. I've done lots of googling and testing and finally found that the query Jay offers in his blog is indeed the fastest solution: SELECT * FROM Table T JOIN (SELECT CEIL(MAX(ID)*RAND()) AS ID FROM Table) AS x ON T.ID >= x.ID LIMIT 1; While common ORDER BY RAND() takes 30-40 seconds on my test table, his query does the work in 0.1 seconds. He explains how this functions in the blog so I'll just skip this and finally move to the odd thing. My table is a common table with a PRIMARY KEY id and other non-indexed stuff like username, age, etc. Here's the thing I am struggling to explain SELECT * FROM table ORDER BY RAND() LIMIT 1; /*30-40 seconds*/ SELECT id FROM table ORDER BY RAND() LIMIT 1; /*0.25 seconds*/ SELECT id, username FROM table ORDER BY RAND() LIMIT 1; /*90 seconds*/ I was sort of expecting to see approximately the same time for all three queries since I am always sorting on a single column. But for some reason this didn't happen. Please let me know if you any ideas about this. I have a project where I need to do fast ORDER BY RAND() and personally I would prefer to use SELECT id FROM table ORDER BY RAND() LIMIT 1; SELECT * FROM table WHERE id=ID_FROM_PREVIOUS_QUERY LIMIT 1; which, yes, is slower than Jay's method, however it is smaller and easier to understand. My queries are rather big ones with several JOINs and with WHERE clause and while Jay's method still works, the query grows really big and complex because I need to use all the JOINs and WHERE in the JOINed (called x in his query) sub request. Thanks for your time!

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  • Form submits correctly in Chrome/FF, but fails altogether in IE/Safari

    - by culov
    I have a form with a css submit button. When a the submit button is clicked, i call a function that executes: document.forms["request"].onsubmit(); What should happen, then, is that the onsubmit method ought to be triggered. This works properly in Chrome/FF, but for some reason IE/Safari will bypass the onsubmit function and simply add the parameter "address=" onto the url as if it were submitting the form and ignoring the onsubmit function. Heres the code for the form: <form id="request" method="get" onsubmit="addLocation(this.address.value); return false;"> <br> <label style="position:relative;left:5px;" for="address">Enter an intersection or address: </label> <br> <br> <input style="height:35px; width:300px;position:relative;bottom:1px;left:10px;" id="address" name="address" class="required address"/> <a style="float:right;right:120px;position:relative;" class="button" onclick="submit();"> <span>Submit Request </span> </a> </form> and what follows are some relevant js functions: function addLocation(address) { if (geocoder) { geocoder.getLocations(address, function (point) { if (!point) { alert(address + " not found"); } else { if (point.Placemark[0].address != submittedString) { submittedString = point.Placemark[0].address; addRow(point.Placemark[0].address); req = "addrequest?truck=" + "coolhaus&address=" + point.Placemark[0].address; alert(req); addRequest(req); request.onreadystatechange = function () {} } } }); } } function addRequest(req) { try { request = new XMLHttpRequest(); } catch (e) { try { request = new ActiveXObject("Microsoft.XMLHTTP"); } catch (e) { alert("XMLHttpRequest error: " + e); } } request.open("GET", req, true); request.send(null); return request; } You can test the form here: http://la.truxmap.com/request?id=grillmastersla Thanks so much!

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  • Python - wxPython What's wrong?

    - by Wallter
    I am trying to write a simple custom button in wx.Python. My code is as follows,(As a side note: I am relatively new to python having come from C++ and C# any help on syntax and function of the code would be great! - knowing that, it could be a simple error. thanks!) Error Traceback (most recent call last): File "D:\Documents\Python2\Button\src\Custom_Button.py", line 10, in <module> class Custom_Button(wx.PyControl): File "D:\Documents\Python2\Button\src\Custom_Button.py", line 13, in Custom_Button Mouse_over_bmp = wx.Bitmap(0) # When the mouse is over File "C:\Python26\lib\site-packages\wx-2.8-msw-unicode\wx\_gdi.py", line 561, in __init__ _gdi_.Bitmap_swiginit(self,_gdi_.new_Bitmap(*args, **kwargs)) TypeError: String or Unicode type required Main.py class MyFrame(wx.Frame): def __init__(self, parent, ID, title): wxFrame.__init__(self, parent, ID, title, wxDefaultPosition, wxSize(400, 400)) self.CreateStatusBar() self.SetStatusText("Program testing custom button overlays") menu = wxMenu() menu.Append(ID_ABOUT, "&About", "More information about this program") menu.AppendSeparator() menu.Append(ID_EXIT, "E&xit", "Terminate the program") menuBar = wxMenuBar() menuBar.Append(menu, "&File"); self.SetMenuBar(menuBar) self.Button1 = Custom_Button(self, parent, -1, "D:/Documents/Python/Normal.bmp", "D:/Documents/Python/Clicked.bmp", "D:/Documents/Python/Over.bmp", "None", wx.Point(200,200), wx.Size(300,100)) EVT_MENU(self, ID_ABOUT, self.OnAbout) EVT_MENU(self, ID_EXIT, self.TimeToQuit) def OnAbout(self, event): dlg = wxMessageDialog(self, "Testing the functions of custom " "buttons using pyDev and wxPython", "About", wxOK | wxICON_INFORMATION) dlg.ShowModal() dlg.Destroy() def TimeToQuit(self, event): self.Close(true) class MyApp(wx.App): def OnInit(self): frame = MyFrame(NULL, -1, "wxPython | Buttons") frame.Show(true) self.SetTopWindow(frame) return true app = MyApp(0) app.MainLoop() Custom Button import wx from wxPython.wx import * class Custom_Button(wx.PyControl): ############################################ ##THE ERROR IS BEING THROWN SOME WHERE IN HERE ## ############################################ # The BMP's Mouse_over_bmp = wx.Bitmap(0) # When the mouse is over Norm_bmp = wx.Bitmap(0) # The normal BMP Push_bmp = wx.Bitmap(0) # The down BMP Pos_bmp = wx.Point(0,0) # The posisition of the button def __init__(self, parent, NORM_BMP, PUSH_BMP, MOUSE_OVER_BMP, pos, size, text="", id=-1, **kwargs): wx.PyControl.__init__(self,parent, id, **kwargs) # Set the BMP's to the ones given in the constructor self.Mouse_over_bmp = wx.Bitmap(MOUSE_OVER_BMP) self.Norm_bmp = wx.Bitmap(NORM_BMP) self.Push_bmp = wx.Bitmap(PUSH_BMP) self.Pos_bmp = pos ############################################ ##THE ERROR IS BEING THROWN SOME WHERE IN HERE ## ############################################ self.Bind(wx.EVT_LEFT_DOWN, self._onMouseDown) self.Bind(wx.EVT_LEFT_UP, self._onMouseUp) self.Bind(wx.EVT_LEAVE_WINDOW, self._onMouseLeave) self.Bind(wx.EVT_ENTER_WINDOW, self._onMouseEnter) self.Bind(wx.EVT_ERASE_BACKGROUND,self._onEraseBackground) self.Bind(wx.EVT_PAINT,self._onPaint) self._mouseIn = self._mouseDown = False def _onMouseEnter(self, event): self._mouseIn = True def _onMouseLeave(self, event): self._mouseIn = False def _onMouseDown(self, event): self._mouseDown = True def _onMouseUp(self, event): self._mouseDown = False self.sendButtonEvent() def sendButtonEvent(self): event = wx.CommandEvent(wx.wxEVT_COMMAND_BUTTON_CLICKED, self.GetId()) event.SetInt(0) event.SetEventObject(self) self.GetEventHandler().ProcessEvent(event) def _onEraseBackground(self,event): # reduce flicker pass def _onPaint(self, event): dc = wx.BufferedPaintDC(self) dc.SetFont(self.GetFont()) dc.SetBackground(wx.Brush(self.GetBackgroundColour())) dc.Clear() dc.DrawBitmap(self.Norm_bmp) # draw whatever you want to draw # draw glossy bitmaps e.g. dc.DrawBitmap if self._mouseIn: # If the Mouse is over the button dc.DrawBitmap(self, self.Mouse_over_bmp, self.Pos_bmp, useMask=False) if self._mouseDown: # If the Mouse clicks the button dc.DrawBitmap(self, self.Push_bmp, self.Pos_bmp, useMask=False)

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  • Exposing C# COM server events to Delphi client applications

    - by hectorsosajr
    My question is very similar to these two: http://stackoverflow.com/questions/1140984/c-component-events http://stackoverflow.com/questions/1638372/c-writing-a-com-server-events-not-firing-on-client However, what worked for them is not working for me. The type library file, does not have any hints of events definitions, so Delphi doesn't see it. The class works fine for other C# applications, as you would expect. COM Server tools: Visual Studio 2010 .NET 4.0 Delphi applications: Delphi 2010 Delphi 7 Here's a simplified version of the code: /// <summary> /// Call has arrived delegate. /// </summary> [ComVisible(false)] public delegate void CallArrived(object sender, string callData); /// <summary> /// Interface to expose SimpleAgent events to COM /// </summary> [ComVisible(true)] [GuidAttribute("1FFBFF09-3AF0-4F06-998D-7F4B6CB978DD")] [InterfaceType(ComInterfaceType.InterfaceIsIDispatch)] public interface IAgentEvents { ///<summary> /// Handles incoming calls from the predictive manager. ///</summary> ///<param name="sender">The class that initiated this event</param> ///<param name="callData">The data associated with the incoming call.</param> [DispId(1)] void OnCallArrived(object sender, string callData); } /// <summary> /// Represents the agent side of the system. This is usually related to UI interactions. /// </summary> [ComVisible(true)] [GuidAttribute("EF00685F-1C14-4D05-9EFA-538B3137D86C")] [ClassInterface(ClassInterfaceType.None)] [ComSourceInterfaces(typeof(IAgentEvents))] public class SimpleAgent { /// <summary> /// Occurs when a call arrives. /// </summary> public event CallArrived OnCallArrived; public SimpleAgent() {} public string AgentName { get; set; } public string CurrentPhoneNumber { get; set; } public void FireOffCall() { if (OnCallArrived != null) { OnCallArrived(this, "555-123-4567"); } } } The type library file has the definitions for the properties and methods, but no events are visible. I even opened the type library in Delphi's viewer to make sure. The Delphi app can see and use any property, methods, and functions just fine. It just doesn't see the events. I would appreciate any pointers or articles to read. Thanks!

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  • How would you organize this Javascript?

    - by Anurag
    How do you usually organize complex web applications that are extremely rich on the client side. I have created a contrived example to indicate the kind of mess it's easy to get into if things are not managed well for big apps. Feel free to modify/extend this example as you wish - http://jsfiddle.net/NHyLC/1/ The example basically mirrors part of the comment posting on SO, and follows the following rules: Must have 15 characters minimum, after multiple spaces are trimmed out to one. If Add Comment is clicked, but the size is less than 15 after removing multiple spaces, then show a popup with the error. Indicate amount of characters remaining and summarize with color coding. Gray indicates a small comment, brown indicates a medium comment, orange a large comment, and red a comment overflow. One comment can only be submitted every 15 seconds. If comment is submitted too soon, show a popup with appropriate error message. A couple of issues I noticed with this example. This should ideally be a widget or some sort of packaged functionality. Things like a comment per 15 seconds, and minimum 15 character comment belong to some application wide policies rather than being embedded inside each widget. Too many hard-coded values. No code organization. Model, Views, Controllers are all bundled together. Not that MVC is the only approach for organizing rich client side web applications, but there is none in this example. How would you go about cleaning this up? Applying a little MVC/MVP along the way? Here's some of the relevant functions, but it will make more sense if you saw the entire code on jsfiddle: /** * Handle comment change. * Update character count. * Indicate progress */ function handleCommentUpdate(comment) { var status = $('.comment-status'); status.text(getStatusText(comment)); status.removeClass('mild spicy hot sizzling'); status.addClass(getStatusClass(comment)); } /** * Is the comment valid for submission */ function commentSubmittable(comment) { var notTooSoon = !isTooSoon(); var notEmpty = !isEmpty(comment); var hasEnoughCharacters = !isTooShort(comment); return notTooSoon && notEmpty && hasEnoughCharacters; } // submit comment $('.add-comment').click(function() { var comment = $('.comment-box').val(); // submit comment, fake ajax call if(commentSubmittable(comment)) { .. } // show a popup if comment is mostly spaces if(isTooShort(comment)) { if(comment.length < 15) { // blink status message } else { popup("Comment must be at least 15 characters in length."); } } // show a popup is comment submitted too soon else if(isTooSoon()) { popup("Only 1 comment allowed per 15 seconds."); } });

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  • Bracketing algorithm when root finding. Single root in "quadratic" function

    - by Ander Biguri
    I am trying to implement a root finding algorithm. I am using the hybrid Newton-Raphson algorithm found in numerical recipes that works pretty nicely. But I have a problem in bracketing the root. While implementing the root finding algorithm I realised that in several cases my functions have 1 real root and all the other imaginary (several of them, usually 6 or 9). The only root I am interested is in the real one so the problem is not there. The thing is that the function approaches the root like a cubic function, touching with the point the y=0 axis... Newton-Rapson method needs some brackets of different sign and all the bracketing methods I found don't work for this specific case. What can I do? It is pretty important to find that root in my program... EDIT: more problems: sometimes due to reaaaaaally small numerical errors, say a variation of 1e-6 in some value the "cubic" function does NOT have that real root, it is just imaginary with a neglectable imaginary part... (checked with matlab) EDIT 2: Much more information about the problem. Ok, I need root finding algorithm. Info I have: The root I need to find is between [0-1] , if there are more roots outside that part I am not interested in them. The root is real, there may be imaginary roots, but I don't want them. Probably all the rest of the roots will be imaginary The root may be double in that point, but I think that actually doesn't mater in numerical analysis problems I need to use the root finding algorithm several times during the overall calculations, but the function will always be a polynomial In one of the particular cases of the root finding, my polynomial will be similar to a quadratic function that touches Y=0 with the point. Example of a real case: The coefficient may not be 100% precise and that really slight imprecision may make the function not to touch the Y=0 axis. I cannot solve for this specific case because in other cases it may be that the polynomial is pretty normal and doesn't make any "strange" thing. The method I am actually using is NewtonRaphson hybrid, where if the derivative is really small it makes a bisection instead of NewRaph (found in numerical recipes). Matlab's answer to the function on the image: roots: 0.853553390593276 + 0.353553390593278i 0.853553390593276 - 0.353553390593278i 0.146446609406726 + 0.353553390593273i 0.146446609406726 - 0.353553390593273i 0.499999999999996 + 0.000000040142134i 0.499999999999996 - 0.000000040142134i The function is a real example I prepared where I know that the answer I want is 0.5 Note: I still haven't check completely some of the answers I you people have give me (Thank you!), I am just trying to give al the information I already have to complete the question.

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  • Pylucene in Python 2.6 + MacOs Snow Leopard

    - by jbastos
    Greetings, I'm trying to install Pylucene on my 32-bit python running on Snow Leopard. I compiled JCC with success. But I get warnings while making pylucene: ld: warning: in build/temp.macosx-10.6-i386-2.6/build/_lucene/__init__.o, file is not of required architecture ld: warning: in build/temp.macosx-10.6-i386-2.6/build/_lucene/__wrap01__.o, file is not of required architecture ld: warning: in build/temp.macosx-10.6-i386-2.6/build/_lucene/__wrap02__.o, file is not of required architecture ld: warning: in build/temp.macosx-10.6-i386-2.6/build/_lucene/__wrap03__.o, file is not of required architecture ld: warning: in build/temp.macosx-10.6-i386-2.6/build/_lucene/functions.o, file is not of required architecture ld: warning: in build/temp.macosx-10.6-i386-2.6/build/_lucene/JArray.o, file is not of required architecture ld: warning: in build/temp.macosx-10.6-i386-2.6/build/_lucene/JObject.o, file is not of required architecture ld: warning: in build/temp.macosx-10.6-i386-2.6/build/_lucene/lucene.o, file is not of required architecture ld: warning: in build/temp.macosx-10.6-i386-2.6/build/_lucene/types.o, file is not of required architecture ld: warning: in /Developer/SDKs/MacOSX10.4u.sdk/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/JCC-2.3-py2.6-macosx-10.3-fat.egg/libjcc.dylib, file is not of required architecture ld: warning: in /Developer/SDKs/MacOSX10.4u.sdk/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/JCC-2.3-py2.6-macosx-10.3-fat.egg/libjcc.dylib, file is not of required architecture build of complete Then I try to import lucene: MacBookPro:~/tmp/trunk python Python 2.6.3 (r263:75184, Oct 2 2009, 07:56:03) [GCC 4.0.1 (Apple Inc. build 5493)] on darwin Type "help", "copyright", "credits" or "license" for more information. >>> import pylucene Traceback (most recent call last): File "<stdin>", line 1, in <module> ImportError: No module named pylucene >>> import lucene Traceback (most recent call last): File "<stdin>", line 1, in <module> File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/lucene-2.9.0-py2.6-macosx-10.6-i386.egg/lucene/__init__.py", line 7, in <module> import _lucene ImportError: dlopen(/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/lucene-2.9.0-py2.6-macosx-10.6-i386.egg/lucene/_lucene.so, 2): Symbol not found: __Z8getVMEnvP7_object Referenced from: /Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/lucene-2.9.0-py2.6-macosx-10.6-i386.egg/lucene/_lucene.so Expected in: flat namespace in /Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/lucene-2.9.0-py2.6-macosx-10.6-i386.egg/lucene/_lucene.so >>> Any hints?

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  • How to do an fetch request with expressions like this on the iPhone?

    - by dontWatchMyProfile
    The documentation has an example on how to retrieve simple values only, rather than managed objects. This remembers a lot SQL using aliases and functions to only retrieve calculated values. So, actually pretty geeky stuff. To get the minimum date from a bunch of records, this is used on the mac: NSFetchRequest *request = [[NSFetchRequest alloc] init]; NSEntityDescription *entity = [NSEntityDescription entityForName:@"Event" inManagedObjectContext:context]; [request setEntity:entity]; // Specify that the request should return dictionaries. [request setResultType:NSDictionaryResultType]; // Create an expression for the key path. NSExpression *keyPathExpression = [NSExpression expressionForKeyPath:@"creationDate"]; // Create an expression to represent the minimum value at the key path 'creationDate' NSExpression *minExpression = [NSExpression expressionForFunction:@"min:" arguments:[NSArray arrayWithObject:keyPathExpression]]; // Create an expression description using the minExpression and returning a date. NSExpressionDescription *expressionDescription = [[NSExpressionDescription alloc] init]; // The name is the key that will be used in the dictionary for the return value. [expressionDescription setName:@"minDate"]; [expressionDescription setExpression:minExpression]; [expressionDescription setExpressionResultType:NSDateAttributeType]; // Set the request's properties to fetch just the property represented by the expressions. [request setPropertiesToFetch:[NSArray arrayWithObject:expressionDescription]]; // Execute the fetch. NSError *error; NSArray *objects = [managedObjectContext executeFetchRequest:request error:&error]; if (objects == nil) { // Handle the error. } else { if ([objects count] > 0) { NSLog(@"Minimum date: %@", [[objects objectAtIndex:0] valueForKey:@"minDate"]; } } [expressionDescription release]; [request release]; Nice, I though - but having a deep look into NSExpression -expressionForFunction:arguments: it turns out that iPhone OS does NOT support the min: function. Well, probably there's a nifty way to use an own function for this kind of stuff on the iPhone as well? Because on thing I'm already worrying about is, how I'm gonna sort a table based on the calculated distance of targets on a map (location-based stuff).

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  • Iterator failure while moving over equal_range in Boost MultiIndex container

    - by Sarah
    I'm making some mistake with my iterators, but I can't see it yet. I have a Boost MultiIndex container, HostContainer hmap, whose elements are boost::shared_ptr to members of class Host. All the indices work on member functions of class Host. The third index is by Host::getHousehold(), where the household member variable is an int. Below, I'm trying to iterate over the range of Hosts matching a particular household (int hhold2) and load the corresponding private member variable Host::id into an array. I'm getting an "Assertion failed: (px != 0), function operator-, file /Applications/boost_1_42_0/boost/smart_ptr/shared_ptr.hpp, line 418" error in runtime when the household size is 2. (I can't yet tell if it happens anytime the household size is 2, or if other conditions must be met.) typedef multi_index_container< boost::shared_ptr< Host >, indexed_by< hashed_unique< const_mem_fun<Host,int,&Host::getID> >, // 0 - ID index ordered_non_unique< const_mem_fun<Host,int,&Host::getAgeInY> >, // 1 - Age index ordered_non_unique< const_mem_fun<Host,int,&Host::getHousehold> > // 2 - Household index > // end indexed_by > HostContainer; typedef HostContainer::nth_index<2>::type HostsByHH; // inside main() int numFamily = hmap.get<2>().count( hhold2 ); int familyIDs[ numFamily ]; for ( int f = 0; f < numFamily; f++ ) { familyIDs[ f ] = 0; } int indID = 0; int f = 0; std::pair< HostsByHH::iterator, HostsByHH::iterator pit = hmap.get<2().equal_range( hhold2 ); cout << "\tNeed to update households of " << numFamily << " family members (including self) of host ID " << hid2 << endl; while ( pit.first != pit.second ) { cout << "Pointing at new family member still in hhold " << ((pit.first))-getHousehold() << "; " ; indID = ((pit.first) )-getID(); familyIDs[ f ] = indID; pit.first++; f++; } What could make this code fail? The above snippet only runs when numFamily 1. (Other suggestions and criticisms are welcome too.) Thank you in advance.

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  • Design pattern question: encapsulation or inheritance

    - by Matt
    Hey all, I have a question I have been toiling over for quite a while. I am building a templating engine with two main classes Template.php and Tag.php, with a bunch of extension classes like Img.php and String.php. The program works like this: A Template object creates a Tag objects. Each tag object determines which extension class (img, string, etc.) to implement. The point of the Tag class is to provide helper functions for each extension class such as wrap('div'), addClass('slideshow'), etc. Each Img or String class is used to render code specific to what is required, so $Img->render() would give something like <img src='blah.jpg' /> My Question is: Should I encapsulate all extension functionality within the Tag object like so: Tag.php function __construct($namespace, $args) { // Sort out namespace to determine which extension to call $this->extension = new $namespace($this); // Pass in Tag object so it can be used within extension return $this; // Tag object } function render() { return $this->extension->render(); } Img.php function __construct(Tag $T) { $args = $T->getArgs(); $T->addClass('img'); } function render() { return '<img src="blah.jpg" />'; } Usage: $T = new Tag("img", array(...); $T->render(); .... or should I create more of an inheritance structure because "Img is a Tag" Tag.php public static create($namespace, $args) { // Sort out namespace to determine which extension to call return new $namespace($args); } Img.php class Img extends Tag { function __construct($args) { // Determine namespace then call create tag $T = parent::__construct($namespace, $args); } function render() { return '<img src="blah.jpg" />'; } } Usage: $Img = Tag::create('img', array(...)); $Img->render(); One thing I do need is a common interface for creating custom tags, ie I can instantiate Img(...) then instantiate String(...), I do need to instantiate each extension using Tag. I know this is somewhat vague of a question, I'm hoping some of you have dealt with this in the past and can foresee certain issues with choosing each design pattern. If you have any other suggestions I would love to hear them. Thanks! Matt Mueller

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  • Vim + OmniCppComplete: Completing on Class Members which are STL containers

    - by Robert S. Barnes
    Completion on class members which are STL containers is failing. Completion on local objects which are STL containers works fine. For example, given the following files: // foo.h #include <string> class foo { public: void set_str(const std::string &); std::string get_str_reverse( void ); private: std::string str; }; // foo.cpp #include "foo.h" using std::string; string foo::get_str_reverse ( void ) { string temp; temp.assign(str); reverse(temp.begin(), temp.end()); return temp; } /* ----- end of method foo::get_str ----- */ void foo::set_str ( const string &s ) { str.assign(s); } /* ----- end of method foo::set_str ----- */ I've generated the tags for these two files using: ctags -R --c++-kinds=+pl --fields=+iaS --extra=+q . When I type temp. in the cpp I get a list of string member functions as expected. But if I type str. omnicppcomplete spits out "Pattern Not Found". I've noticed that the temp. completion only works if I have the using std::string; declaration. How do I get completion to work on my class members which are STL containers? Edit I found that completion on members which are STL containers works if I make the follow modifications to the header: // foo.h #include <string> using std::string; class foo { public: void set_str(const string &); string get_str_reverse( void ); private: string str; }; Basically, if I add using std::string; and then remove the std:: name space qualifier from the string str; member and regenerate the tags file then OmniCppComplete is able to do completion on str.. It doesn't seem to matter whether or not I have let OmniCpp_DefaultNamespaces = ["std", "_GLIBCXX_STD"] set in the .vimrc. The problem is that putting using declarations in header files seems like a big no-no, so I'm back to square one.

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  • Prevent SQL Injection in Dynamic column names

    - by Mr Shoubs
    I can't get away without writing some dynamic sql conditions in a part of my system (using Postgres). My question is how best to avoid SQL Injection with the method I am currently using. EDIT (Reasoning): There are many of columns in a number of tables (a number which grows (only) and is maintained elsewhere). I need a method of allowing the user to decide which (predefined) column they want to query (and if necessary apply string functions to). The query itself is far too complex for the user to write themselves, nor do they have access to the db. There are 1000's of users with varying requirements and I need to remain as flexible as possible - I shouldn't have to revisit the code unless the main query needs to change - Also, there is no way of knowing what conditions the user will need to use. I have objects (received via web service) that generates a condition (the generation method is below - it isn't perfect yet) for some large sql queries. The _FieldName is user editable (parameter name was, but it didn't need to be) and I am worried it could be an attack vector. I put double quotes (see quoted identifier) around the field name in an attempt to sanitize the string, this way it can never be a key word. I could also look up the field name against a list of fields, but it would be difficult to maintain on a timely basis. Unfortunately the user must enter the condition criteria, I am sure there must be more I can add to the sanatize method? and does quoting the column name make it safe? (my limited testing seems to think so). an example built condition would be "AND upper(brandloaded.make) like 'O%' and upper(brandloaded.make) not like 'OTHERBRAND'" ... Any help or suggestions are appreciated. Public Function GetCondition() As String Dim sb As New Text.StringBuilder 'put quote around the table name in an attempt to prevent some sql injection 'http://www.postgresql.org/docs/8.2/static/sql-syntax-lexical.html sb.AppendFormat(" {0} ""{1}"" ", _LogicOperator.ToString, _FieldName) Select Case _ConditionOperator Case ConditionOperatorOptions.Equals sb.Append(" = ") ... End Select sb.AppendFormat(" {0} ", Me.UniqueParameterName) 'for parameter Return Me.Sanitize(sb) End Function Private Function Sanitize(ByVal sb As Text.StringBuilder) As String 'compare against a similar blacklist mentioned here: http://forums.asp.net/t/1254125.aspx sb.Replace(";", "") sb.Replace("'", "") sb.Replace("\", "") sb.Replace(Chr(8), "") Return sb.ToString End Function Public ReadOnly Property UniqueParameterName() As String Get Return String.Concat(":" _UniqueIdentifier) End Get End Property

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  • Linux: How to find all serial devices (ttyS, ttyUSB, ..) without opening them?

    - by Thomas Tempelmann
    What is the proper way to get a list of all available serial ports/devices on a Linux system? In other words, when I iterate over all devices in /dev/, how do I tell which ones are serial ports in the classic way, i.e. those usually supporting baud rates and RTS/CTS flow control? The solution would be coded in C. I ask because I am using a 3rd party library that does this clearly wrong: It appears to only iterate over /dev/ttyS*. The problem is that there are, for instance, serial ports over USB (provided by USB-RS232 adapters), and those are listed under /dev/ttyUSB*. And reading the Serial-HOWTO at Linux.org, I get the idea that there'll be other name spaces as well, as time comes. So I need to find the official way to detect serial devices. Problem is that there appears none documented, or I can't find it. I imagine one way would be to open all files from /dev/tty* and call a specific ioctl() on them that is only available on serial devices. Would that be a good solution, though? Update hrickards suggested to look at the source for "setserial". Its code does exactly what I had in mind: First, it opens a device with: fd = open (path, O_RDWR | O_NONBLOCK) Then it invokes: ioctl (fd, TIOCGSERIAL, &serinfo) If that call returns no error, then it's a serial dev, apparently. I found similar code here, which suggested to also add the O_NOCTTY option. There is one problem with this approach, though: When I tested this code on BSD Unix (i.e. OSX), it worked as well, however serial devices that are provided thru Bluetooth cause the system (driver) to try to connect to the bluetooth device, which takes a while before it'll return with a timeout error. This is caused by just opening the device. And I can imagine that similar things can happen on Linux as well - ideally, I should not need to open the device to figure out its type. I wonder if there's also a way to invoke ioctl functions without an open, or open a device in a way that it does not cause connections to be made? Any ideas?

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