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• Loading page all content and scripts inside another

  - by Robin I Knight

  If you go to this page on our website: http://www.divethegap.com/scuba-diving-programmes-dive-the-gap/dahab-divemaster-training.html The buttons at the bottom that say 'Beginner' 'Open Water Diver' etc.... They take you to another page where you have a series of options and can book. We would like it so that rather than have to navigate to another page it loaded those options and all the scripts that make the calculations in a div on the first page. Depending on which button you press depends on which page it would load inside the div. IFrame does not work as it does not dynamically resize when the collapsible panels are opened. AJAX script at dynamic drive. http://www.dynamicdrive.com/dynamicindex17/ajaxcontent.htm does not work as none of the collapsible panels work, nor does the calculation script. How can this be done. To sum it up it would be like turning the buttons at the bottom of the page into tabs that would display the content from the pages those buttons currently link through to. Is this possible.

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• Protected and Private methods

  - by cabaret

  I'm reading through Beginning Ruby and I'm stuck at the part about private and protected methods. This is a newbie question, I know. I searched through SO for a bit but I couldn't manage to find a clear and newbie-friendly explanation of the difference between private and protected methods. The book gives two examples, the first one for private methods: class Person def initialize(name) set_name(name) end def name @first_name + ' ' + @last_name end private def set_name(name) first_name, last_name = name.split(/\s+/) set_first_name(first_name) set_last_name(last_name) end def set_first_name(name) @first_name = name end def set_last_name(name) @last_name = name end end In this case, if I try p = Person.new("Fred Bloggs") p.set_last_name("Smith") It will tell me that I can't use the set_last_name method, because it's private. All good till there. However, in the other example, they define an age method as protected and when I do fred = Person.new(34) chris = Person.new(25) puts chris.age_difference_with(fred) puts chris.age It gives an error: :20: protected method 'age' called for #<Person:0x1e5f28 @age=25> (NoMethodError) I honestly fail to see the difference between the private and protected methods, it sounds the same to me. Could someone provide me with a clear explanation so I'll never get confused about this again? I'll provide the code for the second example if necessary.

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• dynamic row height

  - by Prasanna Venkatesh

  static NSString *CellIdentifier = @"Cell"; UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@""]; if (cell == nil) { cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease]; } //cell.backgroundView = [[[CustomCell alloc] init] autorelease]; cell.selectedBackgroundView = [[[CustomCell alloc] init] autorelease]; // At end of function, right before return cell: cell.textLabel.backgroundColor = [UIColor clearColor]; // Configure the cell. UILabel *myLabel1 = [[UILabel alloc] initWithFrame:CGRectMake(-30, 3, 300, 22)]; UILabel *myLabel2 = [[UILabel alloc] initWithFrame:CGRectMake(10, 22, 310, 200)]; UILabel *myLabel3 = [[UILabel alloc] initWithFrame:CGRectMake(0, 170, 300, 20)]; Book *aBook = [appDelegate.books objectAtIndex:indexPath.row]; myLabel1.text=aBook.title; myLabel2.text=aBook.description; myLabel3.text=aBook.pubDate; NSString *desc = aBook.description; if ([desc isEqualToString:nil]) { NSLog(@"nullll lll "); } //myLabel2.textAlignment=UITextAlignmentCenter; myLabel2.numberOfLines=5; myLabel2.textColor=[UIColor blueColor]; myLabel2.lineBreakMode=UILineBreakModeWordWrap; myLabel2.font=[UIFont systemFontOfSize:14]; myLabel3.numberOfLines=1; myLabel1.numberOfLines=1; myLabel1.textColor=[UIColor redColor]; myLabel1.font=[UIFont systemFontOfSize:20]; myLabel1.shadowColor=[UIColor redColor]; myLabel1.backgroundColor=[UIColor grayColor]; [cell.contentView addSubview:myLabel1]; [cell.contentView addSubview:myLabel2]; [cell.contentView addSubview:myLabel3]; hi guys! i have this following code, i want to display this from xml file. now its working but static row height. if the xml file dont have data then it leaves it as blank. so i want to change row height according to the data i provide using the mylabel1,2,3.text

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• accessing a value of a nested hash

  - by st

  Hello! I am new to perl and I have a problem that's very simple but I cannot find the answer when consulting my perl book. When printing the result of Dumper($request); I get the following result: $VAR1 = bless( { '_protocol' => 'HTTP/1.1', '_content' => '', '_uri' => bless( do{\(my $o = 'http://myawesomeserver.org:8081/counter/')}, 'URI::http' ), '_headers' => bless( { 'user-agent' => 'Mozilla/5.0 (X11; U; Linux i686; en; rv:1.9.0.4) Gecko/20080528 Epiphany/2.22 Firefox/3.0', 'connection' => 'keep-alive', 'cache-control' => 'max-age=0', 'keep-alive' => '300', 'accept' => 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8', 'accept-language' => 'en-us,en;q=0.5', 'accept-encoding' => 'gzip,deflate', 'host' => 'localhost:8081', 'accept-charset' => 'ISO-8859-1,utf-8;q=0.7,*;q=0.7' }, 'HTTP::Headers' ), '_method' => 'GET', '_handle' => bless( \*Symbol::GEN0, 'FileHandle' ) }, 'HTTP::Server::Simple::Dispatched::Request' ); How can I access the values of '_method' ('GET') or of 'host' ('localhost:8081'). I know that's an easy question, but perl is somewhat cryptic at the beginning. Thank you, St.

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• Extending URIs with 2 queries (i.e. 'viewauthorbooks.php?authorid=4' AND 'orderby=returndate") Possi

  - by Jess

  I have a link in my system as displayed above; 'viewauthorbooks.php?authorid=4' which works fine and generates a page displaying the books only associated with the particular author. However I am implementing another feature where the user can sort the columns (return date, book name etc) and I am using the ORDER BY SQL clause. I have this also working as required for other pages, which do not already have another query in the URI. But for this particular page there is already a paramter returned in the URL, and I am having difficulty in extending it. When the user clicks on the a table column title I'm getting an error, and the original author ID is being lost!! This is the URI link I am trying to use: <th><a href="viewauthorbooks.php?authorid=<?php echo $row['authorid']?>&orderby=returndate">Return Date</a></th> This is so that the data can be sorted in order of Return Date. When I run this; the author ID gets lost for some reason, also I want to know if I am using correct layout to have 2 parameters run in the address? Thanks.

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• How to manipulate *huge* amounts of data

  - by Alejandro

  Hi there! I'm having the following problem. I need to store huge amounts of information (~32 GB) and be able to manipulate it as fast as possible. I'm wondering what's the best way to do it (combinations of programming language + OS + whatever you think its important). The structure of the information I'm using is a 4D array (NxNxNxN) of double-precission floats (8 bytes). Right now my solution is to slice the 4D array into 2D arrays and store them in separate files in the HDD of my computer. This is really slow and the manipulation of the data is unbearable, so this is no solution at all! I'm thinking on moving into a Supercomputing facility in my country and store all the information in the RAM, but I'm not sure how to implement an application to take advantage of it (I'm not a professional programmer, so any book/reference will help me a lot). An alternative solution I'm thinking on is to buy a dedicated server with lots of RAM, but I don't know for sure if that will solve the problem. So right now my ignorance doesn't let me choose the best way to proceed. What would you do if you were in this situation? I'm open to any idea. Thanks in advance!

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• Getting my head around object oriented programing

  - by nLL

  I am entry level .Net developer and using it to develop web sites. I started with classic asp and last year jumped on the ship with a short C# book. As I developed I learned more and started to see that coming from classic asp I always used C# like scripting language. For example in my last project I needed to encode video on the webserver and wrote a code like public class Encoder { Public static bool Encode(string videopath) { ...snip... return true; } } While searching samples related to my project I’ve seen people doing this public class Encoder { Public static Encode(string videopath) { EncodedVideo encoded = new EncodedVideo(); ...snip... encoded.EncodedVideoPath = outputFile; encoded.Success = true; ...snip... } } public class EncodedVideo { public string EncodedVideoPath { get; set; } public bool Success { get; set; } } As I understand second example is more object oriented but I don’t see the point of using EncodedVideo object. Am I doing something wrong? Does it really necessary to use this sort of code in a web app?

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• Summation loop program in Pascal

  - by user2526598

  I am having a bit of an issue with this problem. I am taking a Pascal programming class and this problem was in my logic book. I am required to have the user enter a series of (+) numbers and once he/she enters a (-) number, the program should find the sum of all the (+) numbers. I accomplished this, but now I am attempting part two of this problem, which requires me to utilize a nested loop to run the program x amount of times based on the user's input. The following code is what I have so far and honestly I am stumped: program summation; //Define main program's variables var num, sum, numRun : integer; //Design procedure that will promt user for number of runs procedure numRunLoop ( var numRun : integer ); begin writeln('How many times shall I run this program?'); readln(numRun); end; //Design procedure that will sum a series of numbers //based on user input procedure numPromptLoop( numRun : integer; var num : integer ); var count : integer; begin //Utilize for to establish run limit for count := 1 to numRun do begin //Use repeat to prompt user for numbers repeat writeln('Enter a number: '); readln(num); //Tells program when to sum if num >= 0 then sum := sum + num; until num < 0; end; end; //Design procedure that will display procedure addItion( sum : integer ); begin writeln('The sum is; ', sum); end; begin numRunLoop(numRun); numPromptloop(numRun, num); addItion(sum); readln(); end.

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• Drag and Drop in Silverlight with F# and Asynchronous Workflows

  - by knotig

  Hello everyone! I'm trying to implement drag and drop in Silverlight using F# and asynchronous workflows. I'm simply trying to drag around a rectangle on the canvas, using two loops for the the two states (waiting and dragging), an idea I got from Tomas Petricek's book "Real-world Functional Programming", but I ran into a problem: Unlike WPF or WinForms, Silverlight's MouseEventArgs do not carry information about the button state, so I can't return from the drag-loop by checking if the left mouse button is no longer pressed. I only managed to solve this by introducing a mutable flag. Would anyone have a solution for this, that does not involve mutable state? Here's the relevant code part (please excuse the sloppy dragging code, which snaps the rectangle to the mouse pointer): type MainPage() as this = inherit UserControl() do Application.LoadComponent(this, new System.Uri("/SilverlightApplication1;component/Page.xaml", System.UriKind.Relative)) let layoutRoot : Canvas = downcast this.FindName("LayoutRoot") let rectangle1 : Rectangle = downcast this.FindName("Rectangle1") let mutable isDragged = false do rectangle1.MouseLeftButtonUp.Add(fun _ -> isDragged <- false) let rec drag() = async { let! args = layoutRoot.MouseMove |> Async.AwaitEvent if (isDragged) then Canvas.SetLeft(rectangle1, args.GetPosition(layoutRoot).X) Canvas.SetTop(rectangle1, args.GetPosition(layoutRoot).Y) return! drag() else return() } let wait() = async { while true do let! args = Async.AwaitEvent rectangle1.MouseLeftButtonDown isDragged <- true do! drag() } Async.StartImmediate(wait()) () Thank you very much for your time!

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• Is CakePhp 'standards compliant' when generating HTML, Forms, etc?

  - by dtj

  So I've been reading a lot of "Designing with Web Standards" and really enjoying it. I'm a big CakePhp user, and as I look at the source for various form elements that Cake creates with its FormHelper, I see all sorts of extraneous In the book, he promotes semantic HTML, and writing your markup as simple / generic as possible. So my question is, am I better writing my own HTML in these situations? I really want to work in compliance with XHTML and CSS standards, and it seems I'd spend just as much time (if not more) cleaning up Cakes HTML, when I could just write my own thoughts? p.s. Here's an example in an out of the box form that CakePhp generates using the FormHelper <form id="CompanyAddForm" method="post" action="/omni_cake/companies/add" accept-charset="utf-8"><div style="display:none;"><input type="hidden" name="_method" value="POST" /></div> <div class="input text required"><label for="CompanyName">Name</label><input name="data[Company][name]" type="text" maxlength="50" id="CompanyName" /></div> <div class="input text required"><label for="CompanyWebsite">Website</label><input name="data[Company][website]" type="text" maxlength="50" id="CompanyWebsite" /></div> <div class="input textarea"><label for="CompanyNotes">Notes</label><textarea name="data[Company][notes]" cols="30" rows="6" id="CompanyNotes" ></textarea></div> <div class="submit"><input type="submit" value="Submit" /></div></form>

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• Access 2007 and Special/Unicode Characters in SQL

  - by blockcipher

  I have a small Access 2007 database that I need to be able to import data from an existing spreadsheet and put it into our new relational model. For the most part this seems to work pretty well. Part of the process is attempting to see if a record already exists in a target table using SQL. For example, if I extract book information out of the current row in the spreadsheet, it may contain a title and abstract. I use SQL to get the ID of a matching record, if it exists. This works fine except when I have data that's in a non-English language. In this case, it seems that there is some punctuation that is causing me problems. At least I think it's punctuation as I do have some fields that do not have punctuation and are non-English that do not give me any problems. Is there a built-in function that can escape these characters? Currently I have a small function that will escape the single quote character, but that isn't enough. Or, is there a list of Unicode characters that can interfere with how SQL wants data quoted? Thanks in advance.

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• Beginning Haskell: "not in scope" Unprecedented error

  - by user1071838

  So I just started learning Haskell, and this (http://learnyouahaskell.com) nifty book is giving a lot of help. So yesterday I wrote in a text file doubleMe x = x + x and saved it as double.hs. So after saving that I open up my command prompt, CD to the right folder, type in "ghci" to get haskell started, and then type in >doubleMe 5 10 and everything seems to work. Now today, I do the same thing and this happens (actual copy paste from command line) . . . C:\Users\myName\haskell>ghci GHCi, version 7.0.3: http://www.haskell.org/ghc/ :? for help Loading package ghc-prim ... linking ... done. Loading package integer-gmp ... linking ... done. Loading package base ... linking ... done. Loading package ffi-1.0 ... linking ... done. Prelude> :l double.hs [1 of 1] Compiling Main ( double.hs, interpreted ) Ok, modules loaded: Main. *Main> doubleMe 5 <interactive>:1:1: Not in scope: `doubleMe' So basically, everything was working fine, but now haskell can't find the function I wrote in double.hs. Can anyone tell what is going on? I'm pretty lost and confused. This is just a guess but does it have to do with *Main at all? Thanks for the help.

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• Tablet interface for the physically disabled?

  - by Glenn

  My sister has Cerebral Palsy, which in her case means she has only gross motor control and her speech is slurred. Implications should be obvious: traditional computer/phone/tablet interfaces won't work for her and she can't speak clearly enough for speech recognition software to help her at all. She enjoys reading but has difficulty holding the book and/or turning a page. There are a few options for helping her use a computer, but nothing for tablets or eReaders. That's where you come in. I would like to make (or buy, if such a thing exists) a better interface to an Android tablet that would work for someone with little to no physical dexterity or speech ability. I'd also be interested in work on the Kindle or iPad, but I'm most familiar with Android so I'm starting there. I know Android has Bluetooth capability. Is it possible to interface a joystick to control the Android device? By "control", I mean the entire operating system - selecting an app, launching it, controlling the menus, etc. I want to give her control over the whole thing, not just a specific app. On a PC this can be accomplished by creating a generic USB HID interface and an arcade joystick to move the mouse over the screen and click on thigns. Is it possible to do something like that in Android? Any help you can offer would be greatly appreciated. Thanks!

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• PHP Installer Script

  - by totallymike

  I'm looking to create a fully functional installer for a slightly complicated web application using PHP. Basically, you go to URL/setup.php and you are asked a series of questions, and during the process a database is set up and a config file is populated according to the answers given. A good example of this is how Wordpress handles its install procedure, as well as any number of PHP applications. My question to you, oh great internet, is this: This technique is so prevalent that surely not everyone is re-inventing the wheel, is there a place I can go to find a basic walkthrough (not code, just a description) of the technique. Either that or a good book which outlines if not this specific technique, then the fundamentals relevant to this? I can bang out something ugly and probably make it work myself, but if there's a best known method I'd like to find it. Far more important than having a working function is to have a description of what's going on from step to step. I'd like to have the installer, but I really want to learn how it's done. Thanks, Mike

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• In Java it seems Public constructors are always a bad coding practice

  - by Adam Gent

  This maybe a controversial question and may not be suited for this forum (so I will not be insulted if you choose to close this question). It seems given the current capabilities of Java there is no reason to make constructors public ... ever. Friendly, private, protected are OK but public no. It seems that its almost always a better idea to provide a public static method for creating objects. Every Java Bean serialization technology (JAXB, Jackson, Spring etc...) can call a protected or private no-arg constructor. My questions are: I have never seen this practice decreed or written down anywhere? Maybe Bloch mentions it but I don't own is book. Is there a use case other than perhaps not being super DRY that I missed? EDIT: I explain why static methods are better. .1. For one you get better type inference. For example See Guava's http://code.google.com/p/guava-libraries/wiki/CollectionUtilitiesExplained .2. As a designer of the class you can later change what is returned with a static method. .3. Dealing with constructor inheritance is painful especially if you have to pre-calculate something.

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• Help with Hashmaps in Java

  - by Crystal

  I'm not sure how I use get() to get my information. Looking at my book, they pass the key to get(). I thought that get() returns the object associated with that key looking at the documentation. But I must be doing something wrong here.... Any thoughts? import java.util.*; public class OrganizeThis { /** Add a person to the organizer @param p A person object */ public void add(Person p) { staff.put(p, p.getEmail()); System.out.println("Person " + p + "added"); } /** * Find the person stored in the organizer with the email address. * Note, each person will have a unique email address. * * @param email The person email address you are looking for. * */ public Person findByEmail(String email) { Person aPerson = staff.get(email); return aPerson; } private Map<Person, String> staff = new HashMap<Person, String>(); public static void main(String[] args) { OrganizeThis testObj = new OrganizeThis(); Person person1 = new Person("J", "W", "111-222-3333", "[email protected]"); testObj.add(person1); System.out.println(testObj.findByEmail("[email protected]")); } }

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• How to learn how to program?

  - by twinbornJoint

  I would like to know the best methods for learning to program. I've been directed towards the Python language because I was told it is good for beginners. I ultimately want to make games for OS X/iPhone. My problem is that I understand what I read but I can't apply my knowledge to anything. I am a programming noob. Should I stick with Python? (is there a better language I should be learning?) Where can I learn programming theory? I get very hyper when reading my book sometimes, any tips on staying calm and focusing? What are effective ways to learn how to program? Are there standard exercises for programming? (I feel solving problems helps my understanding immensely) Ultimately I feel like I am in a never ending tunnel that leads me no where. It feels like I am just completely unable to pursue anything in the world of programming, yet it is something I want to do very much. Thanks.

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• Design of std::ifstream class

  - by Nawaz

  Those of us who have seen the beauty of STL try to use it as much as possible, and also encourage others to use it wherever we see them using raw pointers and arrays. Scott Meyers have written a whole book on STL, with title Effective STL. Yet what happened to the developers of ifstream that they preferred char* over std::string. I wonder why the first parameter of ifstream::open() is of type const char*, instead of const std::string &. Please have a look at it's signature: void open(const char * filename, ios_base::openmode mode = ios_base::in ); Why this? Why not this: void open(const string & filename, ios_base::openmode mode = ios_base::in ); Is this a serious mistake with the design? Or this design is deliberate? What could be the reason? I don't see any reason why they have preferred char* over std::string. Note we could still pass char* to the latter function that takes std::string. That's not a problem! By the way, I'm aware that ifstream is a typedef, so no comment on my title.:P. It looks short that is why I used it. The actual class template is : template<class _Elem,class _Traits> class basic_ifstream;

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• How to do binding programmically?

  - by user175908

  Hello, Could anyone identify the problem in this code? (I'm kinda newbie in WPF bindings.) This code executes after chart is loaded when I click a button: I get this error: Update: I dont get that error anymore. Thanks to Tomas. Now no error occur but chart looks completely blank (no columns) Update: Code now looks like this: // create a very simple DataSet var dataSet = new DataSet("MyDataSet"); var table = dataSet.Tables.Add("MyTable"); table.Columns.Add("Name"); table.Columns.Add("Price"); table.Rows.Add("Brick", 1.5d); table.Rows.Add("Soap", 4.99d); table.Rows.Add("Comic Book", 0.99d); // chart series var series = new ColumnSeries() { IndependentValueBinding = new Binding("[Name]"), // How to deal with DependentValueBinding = new Binding("[Price]"), // these two? ItemsSource = dataSet.Tables[0].DefaultView // or maybe I do mistake here? }; // ---------- set additional binding as adviced ------------------ series.SetBinding(ColumnSeries.ItemsSourceProperty, new Binding()); // chart stuff MyChart.Series.Add(series); MyChart.Title = "Names 'n Prices"; // some code to remove legend var style = new Style(typeof(Control)); style.Setters.Add(new Setter(LegendItem.TemplateProperty, null)); MyChart.LegendStyle = style; XAML: <Window x:Class="BindingzTest.MainWindow" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Title="MainWindow" Height="606" Width="988" xmlns:charting="clr-namespace:System.Windows.Controls.DataVisualization.Charting;assembly=System.Windows.Controls.DataVisualization.Toolkit"> <Grid Name="LayoutRoot"> <charting:Chart Name="MyChart" Margin="0,0,573,0" Height="289" VerticalAlignment="Top" /> <Button Content="Button" Height="23" HorizontalAlignment="Left" Margin="272,361,0,0" Name="button1" VerticalAlignment="Top" Width="75" Click="chart1_Loaded" /> </Grid> Thanks for help in advance once more.

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• Question about compilers and how they work

  - by Marin Doric

  This is the C code that frees memory of a singly linked list. It is compiled with Visual C++ 2008 and code works as it should be. /* Program done, so free allocated memory */ current = head; struct film * temp; temp = current; while (current != NULL) { temp = current->next; free(current); current = temp; } But I also encountered ( even in a books ) same code written like this: /* Program done, so free allocated memory */ current = head; while (current != NULL) { free(current); current = current->next; } If I compile that code with my VC++ 2008, program crashes because I am first freeing current and then assigning current-next to current. But obviously if I compile this code with some other complier ( for example, compiler that book author used ) program will work. So question is, why does this code compiled with specific compiler work? Is it because that compiler put instructions in binary file that remember address of current-next although I freed current and my VC++ doesn't. I just want to understand how compilers work.

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• PHP: passing a function with parameters as parameter

  - by Oden

  Hey, I'm not sure that silly question, but I ask: So, if there is an anonymous function I can give it as another anonymous functions parameter, if it has been already stored a variable. But, whats in that case, if I have stored only one function in a variable, and add the second directly as a parameter into it? Can I add parameters to the non-stored function? Fist example (thats what i understand :) ): $func = function($str){ return $str; }; $func2 = function($str){ return $str; }; $var = $func($func2('asd')); var_dump($var); // prints out string(3) "asd" That makes sense for me, but what is with the following one? $func = function($str){ return $str; }; $var = $func(function($str = "asd"){ return $str; }); var_dump($var); /** This prints out: object(Closure)#1 (1) { ["parameter"]=> array(1) { ["$str"]=> string(10) "" } } But why? */ And at the end, can someone recommend me a book or an article, from what i can learn this lambda coding feature of php? Thank you in advance for your answers :)

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• Java Concurrency in practice sample question

  - by andy boot

  I am reading "Java Concurrency in practice" and looking at the example code on page 51. According to the book this piece of code is at risk of of failure if it has not been published properly. Because I like to code examples and break them to prove how they work. I have tried to make it throw an AssertionError but have failed. (Leading me to my previous question) Can anyone post sample code so that an AssertionError is thrown? Rule: Do not modify the Holder class. public class Holder{ private int n; public Holder(int n){ this.n = n; } public void assertSanity(){ if (n != n) { throw new AssertionError("This statement is false"); } } } I have modified the class to make it more fragile but I still can not get an AssertionError thrown. class Holder2{ private int n; private int n2; public Holder2(int n) throws InterruptedException{ this.n = n; Thread.sleep(200); this.n2 = n; } public void assertSanity(){ if (n != n2) { throw new AssertionError("This statement is false"); } } } Is it possible to make either of the above classes throw an AssertionError? Or do we have to accept that they may occasionally do so and we can't write code to prove it?

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• What is wrong with accessing DBI directly?

  - by canavanin

  Hi everyone! I'm currently reading Effective Perl Programming (2nd edition). I have come across a piece of code which was described as being poorly written, but I don't yet understand what's so bad about it, or how it should be improved. It would be great if someone could explain the matter to me. Here's the code in question: sub sum_values_per_key { my ( $class, $dsn, $user, $password, $parameters ) = @_; my %results; my $dbh = DBI->connect( $dsn, $user, $password, $parameters ); my $sth = $dbh->prepare( 'select key, calculate(value) from my_table'); $sth->execute(); # ... fill %results ... $sth->finish(); $dbh->disconnect(); return \%results; } The example comes from the chapter on testing your code (p. 324/325). The sentence that has left me wondering about how to improve the code is the following: Since the code was poorly written and accesses DBI directly, you'll have to create a fake DBI object to stand in for the real thing. I have probably not understood a lot of what the book has so far been trying to teach me, or I have skipped the section relevant for understanding what's bad practice about the above code... Well, thanks in advance for your help!

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• How to (unit-)test data intensive PL/SQL application

  - by doom2.wad

  Our team is willing to unit-test a new code written under a running project extending an existing huge Oracle system. The system is written solely in PL/SQL, consists of thousands of tables, hundreds of stored procedures packages, mostly getting data from tables and/or inserting/updating other data. Our extension is not an exception. Most functions return data from a quite complex SELECT statementa over many mutually bound tables (with a little added logic before returning them) or make transformation from one complicated data structure to another (complicated in another way). What is the best approach to unit-test such code? There are no unit tests for existing code base. To make things worse, only packages, triggers and views are source-controlled, table structures (including "alter table" stuff and necessary data transformations are deployed via channel other than version control). There is no way to change this within our project's scope. Maintaining testing data set seems to be impossible since there is new code deployed to the production environment on weekly basis, usually without prior notice, often changing data structure (add a column here, remove one there). I'd be glad for any suggestion or reference to help us. Some team members tend to be tired by figuring out how to even start for our experience with unit-testing does not cover PL/SQL data intensive legacy systems (only those "from-the-book" greenfield Java projects).

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• WPF: How to bind and update display with DataContext

  - by Am

  I'm trying to do the following thing: I have a TabControl with several tabs. Each TabControlItem.Content points to PersonDetails which is a UserControl Each BookDetails has a dependency property called IsEditMode I want a control outside of the TabControl , named ToggleEditButton, to be updated whenever the selected tab changes. I thought I could do this by changing the ToggleEditButton data context, by it doesn't seem to work (but I'm new to WPF so I might way off) The code changing the data context: private void tabControl1_SelectionChanged(object sender, SelectionChangedEventArgs e) { if (e.Source is TabControl) { if (e.Source.Equals(tabControl1)) { if (tabControl1.SelectedItem is CloseableTabItem) { var tabItem = tabControl1.SelectedItem as CloseableTabItem; RibbonBook.DataContext = tabItem.Content as BookDetails; ribbonBar.SelectedTabItem = RibbonBook; } } } } The DependencyProperty under BookDetails: public static readonly DependencyProperty IsEditModeProperty = DependencyProperty.Register("IsEditMode", typeof (bool), typeof (BookDetails), new PropertyMetadata(true)); public bool IsEditMode { get { return (bool)GetValue(IsEditModeProperty); } set { SetValue(IsEditModeProperty, value); SetValue(IsViewModeProperty, !value); } } And the relevant XAML: <odc:RibbonTabItem Title="Book" Name="RibbonBook"> <odc:RibbonGroup Title="Details" Image="img/books2.png" IsDialogLauncherVisible="False"> <odc:RibbonToggleButton Content="Edit" Name="ToggleEditButton" odc:RibbonBar.MinSize="Medium" SmallImage="img/edit_16x16.png" LargeImage="img/edit_32x32.png" Click="Book_EditDetails" IsChecked="{Binding Path=IsEditMode, Mode=TwoWay}"/> ... There are two things I want to accomplish, Having the button reflect the IsEditMode for the visible tab, and have the button change the property value with no code behind (if posible) Any help would be greatly appriciated.

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