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• Organising files and classes in XCode (iPhone application)

  - by pulegium

  It's a generic question and really a newbie one too, so bear with me... I'm playing with some iPhone development, and trying to create a simple "flip type" application. Nothing sophisticated, let's say on the flip side is a short application summary, bit like 'help' and on the main screen is a simple board game, let's say tic-tac-toe or similar. Now, XCode has generated me 'Main View', 'Flipside View' and 'Application Delegate' folders, with default template files in them. Now the question is where do I create appropriate 'MVC' classes? Let's say (V)iew classes are going to be the ones that have been automatically created. So the Flipside view class is responsible for generating text/images etc on the 'help' view. 'Main View' class is what draws the items on the table and updates the counters, etc. Where should I place the 'controller' class? And also, should it only be dealing with proxying only to the model? According to this the controller method is called from the view and manipulates the method classes. Similarly, the results from model are passed back to the view class by the controller issuing the calls to appropriate view methods. Similarly, where does the model class go? or should I just create a new folder for each, controller and model class files? What I'm after is the best practices, or just a short description how people normally structure their applications. I know it's very specific and also undefined... I came from Django background, so the way stuff is organised there is slightly different. Hope this makes sense, sorry if it's all bit vague, but I have to start somewhere :) And yes I've read quite few docs on the apple developer site, but trouble is that the documents are either going into too much detail about the language/framework/etc and the examples are way too simplistic. Actually, this leads me to the final question, has anyone know any good example of relatively complete application tutorial which I could use as a reference in organising my files?...

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• Cannot redeclare class on a copy of a site

  - by Polity

  I've developed a small SMS utility for a customer in PHP. The details are of non-importance. This project is hosted in: http://project.example.com/customer1 Now a second customer requests almost the same functionality, one cheap way of providing this is to copy the project from the first customer and modify it slightly. So i made a direct copy of the project for customer1 to another folder for customer 2. This project is hosted in: http://project.example.com/customer2 Now when i try and run the project for customer2 (calling a single page), i get the error message: Fatal error: Cannot redeclare class SmsService in /var/www/html/project/customer1/application/service.class.php on line 3 Here, service.class.php is a simple interface with 3 methods: interface SmsService { public function SendSms($mobile, $customerId, $customerName, $message); public function QueryIncomingResponse(); public function CleanExpiredConfirmations($maxConfirmationDays); } printing the backtrace in service.class.php reveals something interresting: #0 require_once() called at [/var/www/html/project/customer2/endpoint/queryIncomingResponse.php:2] Fatal error: Cannot redeclare class SmsService in /var/www/html/project/customer1/application/service.class.php on line 3 Line 2 in queryIncomingResponses is the very first require line there is. Line 3 in service.class.php is the first statement there is in the file (Line 2 is an empty line and line 1 is the php file opening tag). Naturally, I only work with relative requires (double checked this) so there is no way one include/require from customer2 actually refers to a file for customer1. It seems to me that in some way SmsService and other classes gets cached by PHP. (I have little control over the server environment). One solution to this would be namespaces. Unfortunatly, we work with PHP 5.1.7 where namespaces are not a part of the language feature just yet. Another way would be to mimic namespaces by prefixing all classes but this approach just feels dirty. Does anyone have more information on this problem and possibly solutions? Many thanks in advance!

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• Regarding Div Display

  - by user71723

  Hi to all, When i click on button,one div is showing..whenever i click on the body,that div will be hide. How can we achieve this functionality .. i write one code is as below. <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" /> <title>Untitled Document</title> <script language="javascript"> function HideSubMenus(e) { var targ; if (!e) var e = window.event; if (e.target) targ = e.target; else if (e.srcElement) targ = e.srcElement; if (targ.nodeType == 3) // defeat Safari bug targ = targ.parentNode; for (var i=0; i!=5; i++) { if (!targ) { break; } else if (targ.className=="divclass") { return; } targ = targ.parentNode; } if(document.getElementById("showdivid")) { document.getElementById("showdivid").style.display=''; } } </script> </head> <body onclick="HideSubMenus(event);"> <input type="button" name="button" value="Click ME" onclick="document.getElementById('showdivid').style.display='';" /> <div id="showdivid" class="divclass" style="display:none;"> TeSt DIV </div> </body> </html> regards raj

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• Help! I'm a Haskell Newbie

  - by Darknight

  I've only just dipped my toe in the world of Haskell as part of my journey of programming enlightenment (moving on from, procedural to OOP to concurrent to now functional). I've been trying an online Haskell Evaluator. However I'm now stuck on a problem: Create a simple function that gives the total sum of an array of numbers. In a procedural language this for me is easy enough (using recursion) (c#) : private int sum(ArrayList x, int i) { if (!(x.Count < i + 1)) { int t = 0; t = x.Item(i); t = sum(x, i + 1) + t; return t; } } All very fine however my failed attempt at Haskell was thus: let sum x = x+sum in map sum [1..10] this resulted in the following error (from that above mentioned website): Occurs check: cannot construct the infinite type: a = a -> t Please bear in mind I've only used Haskell for the last 30 minutes! I'm not looking simply for an answer but a more explanation of it. Thanks in advanced.

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• Why trigger query fails in the sqlite with Qt?

  - by dexterous_stranger

  I am a beginner in the SQL. I am using SQLite, Qt - on embedded systems. I want to put a trigger here. The trigger is that whenever the primary key Id is greater than 32145, then channelNum=101 should be set. I want to set the attrib name - text also, but I got the compilation issue. I believe that the setting of trigger is the part of DDL - Data definition language. Please let me know that if I am wrong here. Here is my create db code. I get the sql query error. Also please do suggest how to set the text attrib = "COmedy". /** associate db with query **/ QSqlQuery query ( m_demo_db ); /** Foreign keys are disabled by default in sqlite **/ /** Here is the pragma to turn them on first **/ query.exec("PRAGMA foreign_keys = ON;"); if ( false == query.exec()) { qDebug()<<"Pragma failed"; } /** Create Table for storing user preference LCN for DTT **/ qDebug()<<"Create Table postcode.db"; query.prepare(" CREATE TABLE dttServiceList (Id INTEGER PRIMARY KEY, attrib varchar(20), channelNum integer )" ); if ( false == query.exec()) { qDebug()<<"Create dttServiceList table failed"; } /** Try placing trigger here **/ triggerQuery = "CREATE TRIGGER upd_check BEFORE INSERT ON dttServiceList \ FOR EACH ROW \ BEGIN \ IF Id > 32145 THEN SET channelNum=101; \ END IF; \ END; "; query.prepare(triggerQuery); if ( false == query.exec()) { qDebug()<<"Trigger failed !!"; qDebug() << query.lastError(); } Also, how to set the text name in the trigger - I want to SET attrib = "Comedy".

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• Where to place interactive objects in JavaScript?

  - by Chris

  I'm creating a web based application (i.e. JavaScript with jQuery and lots of SVG) where the user interacts with "objects" on the screen (think of DIVs that can be draged around, resized and connected by arraows - like a vector drawing programm or a graphical programming language). As each "object" contains individual information but is allways belonging to a "class" of elements it's obvious that this application should be programmed by using an OOP approach. But where do I store the "objects" best? Should I create a global structure ("registry") with all (JS native) objects and tell them "draw yourself on the DOM"? Or should I avoid such a structure and think of the (relevant) DOM nodes as my objects and attach the relevant data as .data() to them? The first approach is very MVC - but I guess the attachment of all the event handlers will be non trivial. The second approach will handle the events in a trivial way and it doesn't create a duplicate structure, but I guess the usual OO stuff (like methods) will be more complex. What do you recomend? I think the answer will be JavaScript and SVG specific as "usual" programming languages don't have such a highly organized output "canvas".

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• Which Perl moudle can handle variety of date formats with unicode characters ?

  - by ram

  My requirement is parsing xml files which contains wide varieties of timestamps based on the locales at which they are written. They may contain Unicode characters in case of Chinese or Korean locales. I have to parse these timestamps and put then in a standard format something like 2009-11-26 12:40:54 to put them in a oracle database. Sometimes I may not even know the locale and yet I have to parse the timestamps. I am looking for a module that automatically detects the timestamp format (including unicode characters for am and pm in their local language) and converts in to epoch time so that I can convert it back to what ever way I like to. I have gone through similar questions in this forum. Few suggested DateFormat module, and Date::Parse module. The perl distribution I am using is 5.10 so Date::Manip doesn't come as a core module. As I am supposed to use just the basic core modules and few CPAN modules(on request I cannot ask for all), I request you to kindly suggest me a good module that suffices all my requirements. Thanks in advance

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• zend-framework doctrine, and mvc pattern: what should connect data between models and forms?

  - by Skirmantas

  I am learning Zend Framework and Doctrine. I am wondering what is the best practice to connect forms to models and vice versa. I don't know where I should put my code. I have seen in Zendcast video tutorials where author creates methods like mapFormToRecord and mapRecordToForm in form class. Well I guess it is very handy when form is sophisticated and uses many records. Is it a good practice? I somehow believe that form-class should not need to know about data-records. And sometimes we might have model which is used in many forms. So It would be handy to have few functions in that model which would help to prepare data for forms. For example to give an array of id=name pairs so that it might be used in Zend_Form_Element_Select. However I would like to have a consistency. So I don't want to put this code nor in model nor in form because on different situations I act different. So only controller is what is left to deal it. However this will result in code duplication if one form will be used more than in one controller. Moreover controller gets bloated if form is not from the simple ones. Or maybe there is a consistent pattern in those data conversions between forms and models? I think that there is. At least in my simple cases. So maybe a separate class could be a solution? Where should I put such class and how should I name it? Another question: Zend_Form has validators and filter. Doctrine has validators and filters too. Which do we use and when? What is your way of dealing the connections between forms and models? (Sorry if it was hard for you to read my text. I don't have enough knowledge of English language to express myself freely)

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• ASP.Net - Help with datagrid/checkboxes/double submit

  - by Gareth D

  We have a simple datagrid. Each row has a checkbox. The checkbox is set to autopostback, and the code-behind has an event handler for the checkbox check-changed event. This all works as expected, nothing complicated. However, we want to disable the checkboxes as soon as one is checked to prevent a double submit i.e. check box checked, all checkboxes are disabled via client side javascript, form submitted. To achieve this I we are injecting some code into the onclick event as follows (note that the alert is just for testing!): Protected Sub DgAccounts_ItemCreated(ByVal sender As System.Object, ByVal e As System.Web.UI.WebControls.DataGridItemEventArgs) Handles DgAccounts.ItemCreated If e.Item.ItemType = ListItemType.Item Or e.Item.ItemType = ListItemType.AlternatingItem Then Dim chk As CheckBox = CType(e.Item.FindControl("chkItemChecked"), CheckBox) chk.Attributes.Add("onclick", "alert('fired ...');DisableAllDataGridCheckBoxes();") End If End Sub When inspecting the source of the rendered page we get the following: <input id="DgAccounts__ctl2_chkItemChecked" type="checkbox" name="DgAccounts:_ctl2:chkItemChecked" onclick="alert('fired ...');DisableAllDataGridCheckBoxes();setTimeout('__doPostBack(\'DgAccounts$_ctl2$chkItemChecked\',\'\')', 0)" language="javascript" /> It all appears in order, however the server side event does not fire – I believe this is due to the checkbox being disabled, as if we just leave the alert in and remove the call to disable the checkbox it all works fine. Can I force the check-changed event to fire even though the check box is disabled?

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• In Ruby or Python can the very idea of Class be rewritten?

  - by John Berryman

  Howdy All... first time at stack overflow. I'm looking into using some of the metaprogramming features provided by Ruby or Python, but first I need to know the extent to which they will allow me to extend the language. The main thing I need to be able to do is to rewrite the concept of Class. This doesn't mean that I want to rewrite a specific class during run time, but rather I want to make my own conceptualization of what a Class is. To be a smidge more specific here, I want to make something that is like what people normally call a Class, but I want to follow an "open world" assumption. In the "closed world" of normal Classes, if I declare Poodle to be a subclass of Dog to be a subclass of Animal, then I know that Poodle is not going to also be a type of FurCoat. However, in an open world Class, then the Poodle object I've defined may or may not be and object of type FurCoat and we won't know for sure until I explain that I can wear the poodle. (Poor poodle.) This all has to do with a study I'm doing concerning OWL ontologies. Just so you know, I've tried to find information online, but due to the overloading of terms here I haven't found anything helpful. Super thanks, John

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• Javascript not reading value from hidden textBox - JQuery C#

  - by Paul van Valkenburgh

  I'm a non-specialist with JavaScript / JQuery and I'm having trouble figuring out why my script doesn't work. When my C# page loads, I have a hidden textBox txtHiddenKeywordArray which gets dynamically filled with comma separated values like... horse, buggy, track I'm trying to use the highlight functionality in jquery.highlight-3.js where I have a label text field that will contain and highlight the words in the keywords list. I'm using the script <script language="javascript" type="text/javascript"> var myString = document.getElementById('<%=txtHiddenKeywordArray.ClientID%>').val() myArray = myString.split(" "); $(document).ready(function () { for (i = 0; i < myArray.length; i++) $("p").highlight(myArray[i]) }); </script> Here is the textBox declaration : <asp:TextBox ID="txtHiddenKeywordArray" ClientIDMode="Static" runat="server" Visible="false"></asp:TextBox> It worked great when I hard coded the values of var myString. I've tried researching it and keep seeing the same example of the way I have it done. The page does use a MasterPage. Could this affect it? Any idea how I can get the script to see the values from the textbox? Do I need a RegisterStartUpScript or something? Thanks for any help you can provide.

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• Using Visual Studio 2010 Express to create a surface I can draw to

  - by Joel

  I'm coming from a Java background and trying to port a simple version of Conway's Game of Life that I wrote to C# in order to learn the language. In Java, I drew my output by inheriting from JComponent and overriding paint(). My new canvas class then had an instance of the simulation's backend which it could read/manipulate. I was then able to get the WYSIWYG GUI editor (Matisse, from NetBeans) to allow me to visually place the canvas. In C#, I've gathered that I need to override OnPaint() to draw things, which (as far as I know) requires me to inherit from something (I chose Panel). I can't figure out how to get the Windows forms editor to let me place my custom class. I'm also uncertain about where in the generated code I need to place my class. How can I do this, and is putting all my drawing code into a subclass really how I should be going about this? The lack of easy answers on Google suggests I'm missing something important here. If anyone wants to suggest a method for doing this in WPF as well, I'm curious to hear it. Thanks

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• Parsing localized date strings in PHP

  - by Mikeage

  Hi, I have some code (it's part of a wordpress plugin) which takes a text string, and the format specifier given to date(), and attempts to parse it into an array containing hour, minute, second, day, month, year. Currently, I use the following code (note that strtotime is horribly unreliable with things like 01/02/03) // $format contains the string originally given to date(), and $content is the rendered string if (function_exists('date_parse_from_format')) { $content_parsed = date_parse_from_format($format, $content); } else { $content = preg_replace("([0-9]st|nd|rd|th)","\\1",$content); $content_parsed = strptime($content, dateFormatToStrftime($format)); $content_parsed['hour']=$content_parsed['tm_hour']; $content_parsed['minute']=$content_parsed['tm_min']; $content_parsed['day']=$content_parsed['tm_mday']; $content_parsed['month']=$content_parsed['tm_mon'] + 1; $content_parsed['year']=$content_parsed['tm_year'] + 1900; } This actually works fairly well, and seems to handle every combination I've thrown at it. However, recently someone gave me 24 ??????, 2010. This is Russian for November 24, 2010 [the date format was j F, Y], and it is parsed as year = 2010, month = null, day = 24. Are there any functions that I can use that know how to translate both November and ?????? into 11? EDIT: Running print_r(setlocale(LC_ALL, 0)); returns C. Switching back to strptime() seems to fix the problem, but the docs warn: Internally, this function calls the strptime() function provided by the system's C library. This function can exhibit noticeably different behaviour across different operating systems. The use of date_parse_from_format(), which does not suffer from these issues, is recommended on PHP 5.3.0 and later. Is date_parse_from_format() the correct API, and if so, how do I get it to recognize the language?

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• DataTables - Total rowCount - How to cut euro sign in the columns?

  - by Ivan M

  For my DataTable I'm using the fnFooterCallback function to display the total amount of the column, which is working untill the columns contain a special character, like in this case a euro valuta sign. How can I adjust this code so it will not detect the euro sign? "fnFooterCallback": function ( nRow, aaData, iStart, iEnd, aiDisplay ) { /* * Calculate the total market share for all browsers in this table (ie inc. outside * the pagination) */ var iTotal = 0; for ( var i=0 ; i<aaData.length ; i++ ) { iTotal += aaData[i][7]*1; } /* Calculate the market share for browsers on this page */ var iPage = 0; for ( var i=iStart ; i<iEnd ; i++ ) { iPage += aaData[ aiDisplay[i] ][7]*1; } /* Modify the footer row to match what we want */ var nCells = nRow.getElementsByTagName('th'); nCells[1].innerHTML = parseInt(iPage); } Thank you in advance. EDIT With not detecting I mean to str_replace or something like that. Not familiar with javascript language..

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• Is there any need for me to use wstring in the following case

  - by Yan Cheng CHEOK

  Currently, I am developing an app for a China customer. China customer are mostly switch to GB2312 language in their OS encoding. I need to write a text file, which will be encoded using GB2312. I use std::ofstream file I compile my application under MBCS mode, not unicode. I use the following code, to convert CString to std::string, and write it to file using ofstream std::string Utils::ToString(CString& cString) { /* Will not work correctly, if we are compiled under unicode mode. */ return (LPCTSTR)cString; } To my surprise. It just works. I thought I need to at least make use of wstring. I try to do some investigation. Here is the MBCS.txt generated. I try to print a single character named ? (its value is 0xBDC5) When I use CString to carry this character, its length is 2. When I use Utils::ToString to perform conversion to std::string, the returned string length is 2. I write to file using std::ofstream My question is : When I exam MBCS.txt using a hex editor, the value is displayed as BD (LSB) and C5 (MSB). But I am using little endian machine. Isn't hex editor should show me C5 (LSB) and BD (MSB)? I check from wikipedia. GB2312 seems doesn't specific endianness. It seems that using std::string + CString just work fine for my case. May I know in what case, the above methodology will not work? and when I should start to use wstring?

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• Objective-C Definedness

  - by Dan Ray

  This is an agonizingly rookie question, but here I am learning a new language and framework, and I'm trying to answer the question "What is Truth?" as pertains to Obj-C. I'm trying to lazy-load images across the network. I have a data class called Event that has properties including: @property (nonatomic, retain) UIImage image; @property (nonatomic, retain) UIImage thumbnail; in my AppDelegate, I fetch up a bunch of data about my events (this is an app that shows local arts event listings), and pre-sets each event.image to my default "no-image.png". Then in the UITableViewController where I view these things, I do: if (thisEvent.image == NULL) { NSLog(@"Going for this item's image"); UIImage *tempImage = [UIImage imageWithData:[NSData dataWithContentsOfURL: [NSURL URLWithString: [NSString stringWithFormat: @"http://www.mysite.com/content_elements/%@_image_1.jpg", thisEvent.guid]]]]; thisEvent.image = tempImage; } We never get that NSLog call. Testing thisEvent.image for NULLness isn't the thing. I've tried == nil as well, but that also doesn't work.

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• I read 3 pages of a JQuery book and here's my reaction and question

  - by George

  My jQuery reaction to the language's flexible "selectors" is probably rooted in this experience: I once had managed a project where a developer constructed a web page that was used by users to provide very flexible search parameters for a search screen using dynamic sql string building based on the user's specified search parameter. The resulting queries were usually very complicated and involved joins to many tables. One of the options that the user had was to choose from one of 3 an options. Depending on the user's choice for this option, the resulting SQL would need to query a different set of database columns. For example, if choice option "A" were selected, the resulting database columns queried would be prefixed with "A_"; if option "B" were selected, he resulting database columns queried would be prefixed with "B_" and so on. The developer choice to write all the complete SQL assuming that the user selected, for example, option "A" and therefore first constructed SQLs of this type: SQL = "SELECT A_COL1, A_COL2, A_COL3 FROM TABLE ..." and then after constructing one of a million possible variations on the Query From Hell, did something like this: If UserOption = "B" then SQL = SQL.Replace("A_","B_") 'replace everywhere End if He insisted that this was the easiest was to code it, and while I understood that, I was concerned about maintenance of this code. You see, this worked for a while, but as the search options grew and the database columns evolved, the various "REPLACE small substring" with another small substring had unexpected consequences when applied to an evolving database and new search options. My feeling is that code should be written as much as possible such that you can add to it without fear of breaking what is already there. I feel a better approach, though a bit more work, would have been to write a function to return the appropriate target column based on a common set name and the user selected option. OK, so what does this have to do with jQuery selectors? Are the ultra flexible JQuery selectors kind of like perform a "replace all" on a SQL string? Handy as hell but potentially creating a maintenance nightmare?

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• Why can’t I create a database in an empty ASP MVC 2 project using Project->Add->New Item->SQL Server

  - by Dr Dork

  I'm diving head first into ASP MVC and am playing around with creating and manipulating a database. I did a search and found this tutorial for creating a database, however when I follow it, I get this error right at the start when trying to add a new database to my fresh, empty ASP MVC 2 project... A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: SQL Network Interfaces, error: 26 - Error Locating Server/Instance Specified) The only requirement the tutorial mentioned was SQL Server Express, but when I went to download it, it said it was already installed. I'm assuming it was part of the VS 2010 RC I installed and am running. So I don't know what else I need if I am missing something. This is all new to me, so I'm sure I'm missing something obvious here and after I'm done posting this question, I plan to do some more research into the topic of databases and how they work with ASP MVC. In the meantime, I was you could help me answer a couple high level questions... What am I missing/forgetting to do that is causing this error? Any suggestions for good resources/tutorials that focus on using databases with ASP MVC? I've done a lot of database programming in the past, so I'm familiar with the concepts of relational databases and the SQL language. I wish I could find a good resource for learning how to work with them in an ASP dev environment, as well as a good breakdown of all the related technologies used for working with them (i.e. LINQ to SQL). Thanks so much in advance for all your help! I'm going to start researching these questions right now.

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• Subquery with multiple results combined into a single field?

  - by Todd

  Assume I have these tables, from which i need to display search results in a browser: Table: Containers id | name 1 Big Box 2 Grocery Bag 3 Envelope 4 Zip Lock Table: Sale id | date | containerid 1 20100101 1 2 20100102 2 3 20091201 3 4 20091115 4 Table: Items id | name | saleid 1 Barbie Doll 1 2 Coin 3 3 Pop-Top 4 4 Barbie Doll 2 5 Coin 4 I need output that looks like this: itemid itemname saleids saledates containerids containertypes 1 Barbie Doll 1,2 20100101,20100102 1,2 Big Box, Grocery Bag 2 Coin 3,4 20091201,20091115 3,4 Envelope, Zip Lock 3 Pop-Top 4 20091115 4 Zip Lock The important part is that each item type only gets one record/row in the return on the screen. I accomplished this in the past by returning multiple rows of the same item and using a scripting language to limit the output. However, this makes the ui overly complicated and loopy. So, I'm hoping I can get the database to spit out only as many records as there are rows to display. This example may be a bit extreme because of the 2 joins needed to get to the container from the item (through the sale table). I'd be happy for just an example query that outputs this: itemid itemname saleids saledates 1 Barbie Doll 1,2 20100101,20100102 2 Coin 3,4 20091201,20091115 3 Pop-Top 4 20091115 I can only return a single result in a subquery, so I'm not sure how to do this.

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• When is it possible to override top-level bindings in (R7RS) scheme?

  - by Marc

  I have read the current draft of the forthcoming R7RS scheme standard (small language), but I don't understand under which conditions it is not an error to redefine top-level bindings. I guess that it is possible to define or set! a binding that has been introduced at the top-level of a program a second time. But what about imported bindings from an external library? Is it possible to override these bindings by the standard? On page 26/27 of the report, it says: The top level of a program may also include import declarations. In a library declaration, it is an error to import the same identifier more than once with different bindings, or to redefine or mutate an imported binding with define, define-syntax or set!. However, a REPL should permit these actions. Does it mean that redefining is only an error when it does happen in libraries for imported bindings? I understand that it prohibits optimisations by compilers if the compiler does not know whether, say + still means the built-in addition or is any other user-specified error. But from this perspective, it does not make sense to restrict forbidding to rebind on the library level, when it would also make sense (at least) for imported bindings in programs. P.S.: As this is all about the environment of a scheme program: am I right in saying that environments are not first class citizens because one cannot get hold of the current environment? (Which, in turn, allows a compiled program to forget about the chosen names of the bindings.)

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• How to call JS function within .js file into .jsp file?

  - by Simple-Solution

  I am trying to call a javaScript function that's in .../js/index.js file to .../index.jsp file. Any suggestion would be helpful. Here is code within both file: index.js function testing() { if ("c" + "a" + "t" === "cat") { document.writeln("Same"); } else { document.writeln("Not same"); }; }; index.jsp <%@ page language="java" contentType="text/html; charset=ISO-8859-1" pageEncoding="ISO-8859-1"%> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> <title>Insert title here</title> </head> <body> <script type="text/javascript" src="js/index.js"> <!-- I want to call testing(); function here --> </script> </body> </html>

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• What's the *right* way to handle a POST in FP?

  - by Malvolio

  I'm just getting started with FP and I'm using Scala, which may not be the best way, since I can always fall back to an imperative style if the going gets tough. I'd just rather not. I've got a very specific question that points to a broader lacuna in my understanding of FP. When a web application is processing a GET request, the user wants information that already exists on the web-site. The application only has to process and format the data in some way. The FB way is clear. When a web application is processing a POST request, the user wants change the information held on the site. True, the information is not typically held in application variables, it's in a database or a flat-file, but still, I get the feeling I'm not grokking FP properly. Is there a pattern for handling updates to static data in an FP language? My vague picture of this is that the application is handed the request and the then-current site state. The application does its thing and returns the new site-state. If the current site-state hasn't changed since the application started, the new state becomes the current state and the reply is sent back to the browser (this is my dim image of Clojure's style); if the current state has been changed (by another thread, well, something else happens ...

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• Which is the event listener after doSave() in Symfony?

  - by fesja

  Hi, I've been looking at this event-listeners page http://www.doctrine-project.org/documentation/manual/1_1/pl/event-listeners and I'm not sure which is the listener I have to use to make a change after the doSave() method in the BaseModelForm.class.php. // PlaceForm.class.php protected function doSave ( $con = null ) { ... parent::doSave($con); .... // Only for new forms, insert place into the tree if($this->object->level == null){ $parent = Place::getPlace($this->getValue('parent'), Language::getLang()); ... $node = $this->object->getNode(); $method = ($node->isValidNode() ? 'move' : 'insert') . 'AsFirstChildOf'; $node->$method($parent); //calls $this->object->save internally } return; } What I want to do is to make a custom slug with the ancestors' name of that new place. So if I inserting "San Francisco", the slug would be "usa-california-san-francisco" public function postXXXXXX($event) { ... $event->getInvoker()->slug = $slug; } The problem is that I'm inserting a new object with no reference to its parent. After it's saved, I insert it to the tree. So I can't change the slug until then. I think a Transaction listener could work, but I'm use there is a better way I'm not seeing right now. thanks!

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• How can I implement a splay tree that performs the zig operation last, not first?

  - by Jakob

  For my Algorithms & Data Structures class, I've been tasked with implementing a splay tree in Haskell. My algorithm for the splay operation is as follows: If the node to be splayed is the root, the unaltered tree is returned. If the node to be splayed is one level from the root, a zig operation is performed and the resulting tree is returned. If the node to be splayed is two or more levels from the root, a zig-zig or zig-zag operation is performed on the result of splaying the subtree starting at that node, and the resulting tree is returned. This is valid according to my teacher. However, the Wikipedia description of a splay tree says the zig step "will be done only as the last step in a splay operation" whereas in my algorithm it is the first step in a splay operation. I want to implement a splay tree that performs the zig operation last instead of first, but I'm not sure how it would best be done. It seems to me that such an algorithm would become more complex, seeing as how one needs to find the node to be splayed before it can be determined whether a zig operation should be performed or not. How can I implement this in Haskell (or some other functional language)?

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• How do I call Matlab in a script on Windows?

  - by Benjamin Oakes

  I'm working on a project that uses several languages: SQL for querying a database Perl/Ruby for quick-and-dirty processing of the data from the database and some other bookkeeping Matlab for matrix-oriented computations Various statistics languages (SAS/R/SPSS) for processing the Matlab output Each language fits its niche well and we already have a fair amount of code in each. Right now, there's a lot of manual work to run all these steps that would be much better scripted. I've already done this on Linux, and it works relatively well. On Linux: matlab -nosplash -nodesktop -r "command" or echo "command" | matlab -nosplash -nodesktop ...opens Matlab in a "command line" mode. (That is, no windows are created -- it just reads from STDIN, executes, and outputs to STDOUT/STDERR.) My problem is that on Windows (XP and 7), this same code opens up a window and doesn't read from / write to the command line. It just stares me blankly in the face, totally ignoring STDIN and STDOUT. How can I script running Matlab commands on Windows? I basically want something that will do: ruby database_query.rb perl legacy_code.pl ruby other_stuff.rb matlab processing_step_1.m matlab processing_step_2.m # etc, etc. I've found out that Matlab has an -automation flag on Windows to start an "automation server". That sounds like overkill for my purposes, and I'd like something that works on both platforms. What options do I have for automating Matlab in this workflow?

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