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• Getting value of "System.Windows.Controls.TextBlock" when binding to Silverlight ComboBox

  - by sipwiz

  I'm attempting to use a Silverlight ComboBox with a static list of elements in a very simple binding scenario. The problem is the selected item is not returning me the Text of the TextBlock within the ComboBox and is instead returning "System.Windows.Controls.TextBlock". My XAML is: <ComboBox SelectedValue="{Binding Country, Mode=TwoWay, NotifyOnValidationError=True, ValidatesOnExceptions=True}"> <TextBlock FontSize="11" Text="Afghanistan" /> <TextBlock FontSize="11" Text="Albania" /> <TextBlock FontSize="11" Text="Algeria" /> </ComboBox> In my C# file I'm binding to the ComboBox using: Customer customer = new Customer() { Country = "Albania" }; DataContext = customer; The binding does not result in Albania as the selected country and updating the ComboBox choice results in the Country being set to "System.Windows.Controls.TextBlock". I've tried fiddling around with DisplayMemberPath and SelectedValuePath but haven't found the answer. I suspect it's something really simple I'm missing.

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• UserControl/TreeView Problem....Not getting result during runtime..

  - by Samiul

  Hi all, My problem is, I'm using a TreeView in a UserControl. While debugging, I can see the results are adding in the TreeView but it's not happening when I'm using that UserControl onto my MainForm. The UserControl containing the TreeView remains blank during runtime of the main application. I've also referenced the UserControl project with my Main project. Here I'm giving my code for helping me out. Thanks in advance. Code: In the UserControl class: public override void Refresh() { PopulateTreeView(); } private void PopulateTreeView() { TreeNodeCollection treeNodeCollection; treeNodeCollection = CreateParentNode("My Information"); CreateChildNode(treeNodeCollection, "Name"); CreateChildNode(treeNodeCollection, "Address"); this.Update(); myTreeView.ExpandAll(); } private TreeNodeCollection CreateParentNode(string parentNode) { TreeNode treeNode = new TreeNode(parentNode); myTreeView.Nodes.Add(treeNode); return treeNode.Nodes; } private void CreateChildNode(TreeNodeCollection nodeCollection, string itemName) { TreeNode treeNode = new TreeNode(itemName); nodeCollection.Add(treeNode); } In my MainForm: private void button1_Click(object sender, EventArgs e) { UserControl userControl = new UserControl(); userControl.Refresh(); }

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• Getting stack trace from a running Python application

  - by Sebastjan Trepca

  I have this Python application that gets stuck from time to time and I can't find out where. Is there any way to signal Python interpreter to show you the exact code that he's running (somekind of stacktrace on-the-fly)?

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• Custom action getting published multiple times on user's timeline for same object

  - by serpent403

  I just noticed that when I publish an action on the user's timeline for the same object multiple times, using facebook's 'built-in' action type (eg: 'read' an article), i get an error response, something like "action is already associated to the user on this object". But when i try to do the same for a custom action that i created(eg: 'agreed' with an article), I don't get any error message, instead the actions gets published multiple times. I want my custom action to behave just like facebook's default action-type.

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• Getting an array of nodes related to a category term with the Drupal API

  - by JoseMarmolejos

  I have a simple one level deep vocabulary taxonomy. Something like Vocabulary-Term-Node. What I want to know is if there's a built in function to get an array of nodes related to a single term, something like taxonomy_select_nodes() but that would return an array of nodes instead of a string.

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• Javascript Getting Objects to Fallback to One Another

  - by Ian

  Here's a ugly bit of Javascript it would be nice to find a workaround. Javascript has no classes, and that is a good thing. But it implements fallback between objects in a rather ugly way. The foundational construct should be to have one object that, when a property fails to be found, it falls back to another object. So if we want a to fall back to b we would want to do something like: a = {sun:1}; b = {dock:2}; a.__fallback__ = b; then a.dock == 2; But, Javascript instead provides a new operator and prototypes. So we do the far less elegant: function A(sun) { this.sun = sun; }; A.prototype.dock = 2; a = new A(1); a.dock == 2; But aside from elegance, this is also strictly less powerful, because it means that anything created with A gets the same fallback object. What I would like to do is liberate Javascript from this artificial limitation and have the ability to give any individual object any other individual object as its fallback. That way I could keep the current behavior when it makes sense, but use object-level inheritance when that makes sense. My initial approach is to create a dummy constructor function: function setFallback(from_obj, to_obj) { from_obj.constructor = function () {}; from_obj.constructor.prototype = to_obj; } a = {sun:1}; b = {dock:2}; setFallback(a, b); But unfortunately: a.dock == undefined; Any ideas why this doesn't work, or any solutions for an implementation of setFallback? (I'm running on V8, via node.js, in case this is platform dependent)

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• Getting text position while parsing pdf with Quartz 2D

  - by Koteg

  Hi guys, another question regarding pdf parsing... Just read PDF Reference version 1.7 "5.3.1 Text-Positioning Operators" and I am a little bit confused. I wrote some code to get transformation matrix and initial text position. CGPDFOperatorTableSetCallback (table, "MP", &op_MP);//Define marked-content point CGPDFOperatorTableSetCallback (table, "DP", &op_DP);//Define marked-content point with property list CGPDFOperatorTableSetCallback (table, "BMC", &op_BMC);//Begin marked-content sequence CGPDFOperatorTableSetCallback (table, "BDC", &op_BDC);//Begin marked-content sequence with property list CGPDFOperatorTableSetCallback (table, "EMC", &op_EMC);//End marked-content sequence //Text State operators CGPDFOperatorTableSetCallback(table, "Tc", &op_Tc); CGPDFOperatorTableSetCallback(table, "Tw", &op_Tw); CGPDFOperatorTableSetCallback(table, "Tz", &op_Tz); CGPDFOperatorTableSetCallback(table, "TL", &op_TL); CGPDFOperatorTableSetCallback(table, "Tf", &op_Tf); CGPDFOperatorTableSetCallback(table, "Tr", &op_Tr); CGPDFOperatorTableSetCallback(table, "Ts", &op_Ts); //text showing operators CGPDFOperatorTableSetCallback(table, "TJ", &op_TJ); CGPDFOperatorTableSetCallback(table, "Tj", &op_Tj); CGPDFOperatorTableSetCallback(table, "'", &op_apostrof); CGPDFOperatorTableSetCallback(table, "\"", &op_double_apostrof); //text positioning operators CGPDFOperatorTableSetCallback(table, "Td", &op_Td); CGPDFOperatorTableSetCallback(table, "TD", &op_TD); CGPDFOperatorTableSetCallback(table, "Tm", &op_Tm); CGPDFOperatorTableSetCallback(table, "T*", &op_T); //text object operators CGPDFOperatorTableSetCallback(table, "BT", &op_BT);//Begin text object CGPDFOperatorTableSetCallback(table, "ET", &op_ET);//End text object So this is the output after application lunch: 2010-09-02 15:09:23.041 testSearch[8251:207] op_BT begin Integer value: 0 2010-09-02 15:09:23.043 testSearch[8251:207] op_BT end 2010-09-02 15:09:23.043 testSearch[8251:207] op_Tf begin Integer value: 1 2010-09-02 15:09:23.044 testSearch[8251:207] op_Tf end 2010-09-02 15:09:23.044 testSearch[8251:207] op_Tm begin Float value: 557.364197 2010-09-02 15:09:23.045 testSearch[8251:207] op_Tm end 2010-09-02 15:09:23.045 testSearch[8251:207] op_TJ begin 2010-09-02 15:09:23.046 testSearch[8251:207] Array string value [0]: F 2010-09-02 15:09:23.046 testSearch[8251:207] Array integer value [1]: 94985208 2010-09-02 15:09:23.047 testSearch[8251:207] Array string value [2]: r 2010-09-02 15:09:23.047 testSearch[8251:207] Array integer value [3]: 94985208 2010-09-02 15:09:23.048 testSearch[8251:207] Array string value [4]: o 2010-09-02 15:09:23.048 testSearch[8251:207] Array integer value [5]: 94985208 2010-09-02 15:09:23.049 testSearch[8251:207] Array string value [6]: m s 2010-09-02 15:09:23.049 testSearch[8251:207] Array integer value [7]: 94985208 2010-09-02 15:09:23.049 testSearch[8251:207] Array string value [8]: a 2010-09-02 15:09:23.050 testSearch[8251:207] Array integer value [9]: 94985208 2010-09-02 15:09:23.050 testSearch[8251:207] Array string value [10]: m 2010-09-02 15:09:23.051 testSearch[8251:207] Array integer value [11]: 94985208 2010-09-02 15:09:23.051 testSearch[8251:207] Array string value [12]: p 2010-09-02 15:09:23.052 testSearch[8251:207] Array integer value [13]: 94985208 2010-09-02 15:09:23.053 testSearch[8251:207] Array string value [14]: l 2010-09-02 15:09:23.054 testSearch[8251:207] Array integer value [15]: 94985208 2010-09-02 15:09:23.055 testSearch[8251:207] Array string value [16]: e t 2010-09-02 15:09:23.055 testSearch[8251:207] Array integer value [17]: 94985208 2010-09-02 15:09:23.057 testSearch[8251:207] Array string value [18]: o r 2010-09-02 15:09:23.057 testSearch[8251:207] Array integer value [19]: 94985208 2010-09-02 15:09:23.058 testSearch[8251:207] Array string value [20]: e 2010-09-02 15:09:23.058 testSearch[8251:207] Array integer value [21]: 94985208 2010-09-02 15:09:23.059 testSearch[8251:207] Array string value [22]: s 2010-09-02 15:09:23.059 testSearch[8251:207] Array integer value [23]: 94985208 2010-09-02 15:09:23.060 testSearch[8251:207] Array string value [24]: u 2010-09-02 15:09:23.061 testSearch[8251:207] Array integer value [25]: 94985208 2010-09-02 15:09:23.061 testSearch[8251:207] Array string value [26]: l 2010-09-02 15:09:23.062 testSearch[8251:207] Array integer value [27]: 94985208 2010-09-02 15:09:23.062 testSearch[8251:207] Array string value [28]: t 2010-09-02 15:09:23.063 testSearch[8251:207] op_TJ end If someone is familiar with text matrix and text positioning operators it would be nice to explain how all those thing work. How to calculate text position (or glyph?) using Tm (transformation matrix and other data)?

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• JTable - Getting a cell into Edit mode on pressing Tab

  - by Luhar

  This is possibly has a trivial solution, but I am at the end of my tether so I hope somebody can help out. I use a JTable which has a custom renderer and a custom editor for a set of columns. The renderer uses a JLabel component and the editor uses a JSpinner component. Our users want to be able to enter values in a column, and then press TAB or ENTER to move to the next editable cell in the table. If I understand correctly, this is the default behaviour for a JTable. However, this doesn't seem to work correctly for me. Until the user clicks on the cell, only the JLabel is displayed. The JSpinner (i.e. CellEditor) is only displayed when a user double clicks on the cell. So, it looks like the cell is going into "edit" mode only on MouseEvents, but not when it has focus. How do I get the cell to go into edit mode as soon as it has focus?

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• Drupal - Getting node id from view to customise link in block

  - by hfidgen

  I got a little problem with Drupal (again) in that I'm trying to work out how I can build a block which is able to show the node ID of the view page the block is currently sitting on. I'm using views to build a large chunk of my site, but I need to be able to make "intelligent" blocks in PHP mode which will have dynamic content depending on what the view is displaying. So.. how can I go about finding the $nid which a view is currently displaying?! Any ideas?

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• Getting "stack level too deep" error when deploying with Capistrano, Rails 3.1 ruby 1.9.2

  - by Victor S

  Here is the log for the cap deploy script output around where the error occurs. Anny suggestions why this might be happening? Thanks! [yup.la] executing command [yup.la] sh -c 'cd /srv/www/portrait/releases/20120406051647 && bundle exec rake RAILS_ENV=production RAILS_GROUPS=assets assets:precompile' ** [out :: yup.la] rake aborted! ** [out :: yup.la] ** [out :: yup.la] stack level too deep ** [out :: yup.la] (in /srv/www/portrait/releases/20120406051647/app/assets/stylesheets/mobile.css.scss) ** [out :: yup.la] ** [out :: yup.la] Tasks: TOP => assets:precompile:primary ** [out :: yup.la] (See full trace by running task with --trace) ** [out :: yup.la] command finished in 30868ms *** [deploy:update_code] rolling back * executing "rm -rf /srv/www/portrait/releases/20120406051647; true" servers: ["yup.la"] [yup.la] executing command [yup.la] sh -c 'rm -rf /srv/www/portrait/releases/20120406051647; true' command finished in 288ms failed: "sh -c 'cd /srv/www/portrait/releases/20120406051647 && bundle exec rake RAILS_ENV=production RAILS_GROUPS=assets assets:precompile'" on yup.la /Users/victorstan/Sites/portrait ?

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• Twitter API - oauth gem - not getting callback

  - by haries

  I redirect the user of my application to Twitter for oauth style authentication using my app's request_token. The user is able to enter username and password on Twitter's page BUT then, instead of calling back my application, Twitter displays a page You've successfully granted access to MyAppName! Simply return to MyAppName and enter the following PIN to complete the process. 123456 Why is this happening? I have set the callback url in my app's settings. Thanks

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• Getting rid of "static" references in C#

  - by DevEight

  Hello. I've recently begun learning C# but have encountered an annoying problem. Every variable I want available to all functions in my program I have to put a "static" in front of and also every function. What I'd like to know is how to avoid this, if possible? Also, small side question: creating public variables inside functions? This is what my program looks like right now, and I want to basically keep it like that, without having to add "static" everywhere: using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Net; using System.Threading; using System.Net.Sockets; namespace NetworkExercise { class Client { public IPAddress addr; public int port; public string name; public Thread thread; public TcpClient tcp; public NetworkStream stream; public Client(IPAddress addr, int port, string name, NetworkStream stream) { } } class Program { //NETWORK TcpListener tcpListener; Thread listenThread; ASCIIEncoding encoder = new ASCIIEncoding(); //DATA byte[] buffer = new byte[4096]; string servIp; int servPort; //CLIENT MANAGEMENT int clientNum; static void Main(string[] args) { beginConnect(); } public void beginConnect() { Console.Write("Server IP (leave blank if you're the host): "); servIp = Console.ReadLine(); Console.Write("Port: "); servPort = Console.Read(); tcpListener = new TcpListener(IPAddress.Any, servPort); listenThread = new Thread(new ThreadStart(listenForClients)); listenThread.Start(); } public void listenForClients() { tcpListener.Start(); Console.WriteLine("Listening for clients..."); while (true) { Client cl = new Client(null, servPort, null, null); cl.tcp = tcpListener.AcceptTcpClient(); ThreadStart pts = delegate { handleClientCom(cl); }; cl.thread = new Thread(pts); cl.thread.Start(); } } public void handleClientCom(Client cl) { cl.stream = cl.tcp.GetStream(); } } }

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• getting posts from other site network in wordpress 3.0

  - by askkirati

  hello, i have set up the new wordpress 3.0 with multisite network capabilities. What i want to do is get and show blogs from other network site in the main blog. Like if i have set up the blog at example.com and i have other network sites at articles.example.com, movies.example.com. I want to get the posts from the articles.example.com and movies.example.com to show up in the main site at example.com. Is there any parameter in query_post to get the post from different network sites?

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• Getting user data from Active Directory using PL/SQL

  - by David Neale

  I had a discussion today regarding an Oracle procedure I wrote some time ago. I wanted to get 7500 user email addresses from Active Directory using PL/SQL. AD will return a maximum of 1000 rows and the LDAP provider used by Oracle will not support paging. Therefore, my solution was to filter on the last two characters of the sAMAccountName (*00,*01,*02...etc.). This results in 126 queries (100 for account names ending in digits, 26 for those ending in a letter...this was sufficient for my AD setup). The person I was speaking to (it was a job interview by the way) said he could have done it a better way, but he would not tell me what that method was. Could anybody hazard a guess at what this method was?

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• Getting a linq table to be dynamically sent to a method

  - by Damian Spaulding

  I have a procedure: var Edit = (from R in Linq.Products where R.ID == RecordID select R).Single(); That I would like to make "Linq.Products" Dynamic. Something like: protected void Page_Load(object sender, EventArgs e) { something(Linq.Products); } public void something(Object MyObject) { System.Data.Linq.Table<Product> Dynamic = (System.Data.Linq.Table<Product>)MyObject; var Edit = (from R in Dynamic where R.ID == RecordID select R).Single(); My problem is that I my "something" method will not be able to know what table has been sent to it. so the static line: System.Data.Linq.Table Dynamic = (System.Data.Linq.Table)MyObject; Would have to reflect somthing like: System.Data.Linq.Table Dynamic = (System.Data.Linq.Table)MyObject; With being a dynamic catch all variable so that Linq can just execute the code just like I hand coded it statically. I have been pulling my hair out with this one. Please help.

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• Getting an icon to always be unrotated regardless of parent rotations in WPF

  - by Jeff Moser

  Is there an easy way in WPF to specify the orientation of an icon (or Button, or any WPF object) so that it always effectively remains unrotated regardless of the rotations of the parent transforms? For example, I'd like to have an icon like this: + + + + + +++++ + + + + + + + However, if I dock it to the left side, it'd by default look like this: +++++ + + + +++++ +++ + and if I docked it to the right, it'd be like this: + +++ +++++ + + + +++++ Is there a way to make it always be: + + + + + +++++ + + + + + + + ? I know I could manually track where it's docked and rotate it appropriately, but I was wondering if there's a clever way to effectively give the icon "gravity" to always point down. Thanks!

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• Java Inheritance - Getting a Parameter from Parent Class

  - by Aaron

  I'm trying to take one parameter from the parent class of Car and add it to my array (carsParked), how can i do this? Parent Class public class Car { protected String regNo; //Car registration number protected String owner; //Name of the owner protected String carColor; /** Creates a Car object * @param rNo - registration number * @param own - name of the owner **/ public Car (String rNo, String own, String carColour) { regNo = rNo; owner = own; carColor = carColour; } /** @return The car registration number **/ public String getRegNo() { return regNo; } /** @return A String representation of the car details **/ public String getAsString() { return "Car: " + regNo + "\nColor: " + carColor; } public String getColor() { return carColor; } } Child Class public class Carpark extends Car { private String location; // Location of the Car Park private int capacity; // Capacity of the Car Park - how many cars it can hold private int carsIn; // Number of cars currently in the Car Park private String[] carsParked; /** Constructor for Carparks * @param loc - the Location of the Carpark * @param cap - the Capacity of the Carpark */ public Carpark (String locations, int room) { location = locations; capacity = room; } /** Records entry of a car into the car park */ public void driveIn() { carsIn = carsIn + 1; } /** Records the departure of a car from the car park */ public void driveOut() { carsIn = carsIn - 1; } /** Returns a String representation of information about the carpark */ public String getAsString() { return location + "\nCapacity: " + capacity + " Currently parked: " + carsIn + "\n*************************\n"; } }

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• Getting child elements that are related to a parent in same table

  - by Madawar

  I have the following database schema class posts(Base): __tablename__ = 'xposts' id = Column(Integer, primary_key=True) class Comments(Base): __tablename__ = 'comments' id = Column(Integer, primary_key=True) comment_parent_id=Column(Integer,unique=True) #comment_id fetches comment of a comment ie the comment_parent_id comment_id=Column(Integer,default=None) comment_text=Column(String(200)) Values in database are 1 12 NULL Hello First comment 2 NULL 12 First Sub comment I want to fetch all Comments and sub comments of a post using sqlalchemy and have this so far qry=session.query(Comments).filter(Comments.comment_parent_id!=None) print qry.count() Is there a way i can fetch the all the subcomments of a comment in a query i have tried outerjoin on the same table(comments) and it seemed stupid and it failed.

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• Getting below error when trying to register a generic class with a implementation using .net 2.0

  - by Gaurav Saxena

  Code: StructureMapConfiguration.BuildInstancesOf().AsSingletons().TheDefaultIsConcreteType(); Error: StructureMap Exception Code: 190 Can not create a Generic PluginFamily for PluginFamily MIGExcel.Service.IPersistenceService1[[MIGExcel.Model.Contact, WizardModel, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]]. Check that the basic type MIGExcel.Service.IPersistenceService1 is configured as a PluginFamily. These Generic types are configured within StructureMap as PluginFamily's: MIGExcel.Service.IPersistenceService`1[[MIGExcel.Model.Contact, WizardModel, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]],MIGExcel.Service;

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• Getting the current ProcessID in .NET

  - by plaureano

  What's the simplest way to obtain the current process ID from within your own application, using the .NET Framework?

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• data is not getting ordered by date

  - by raging_boner

  Can't get list sorted by date. How to show data ordered by date? XDocument doc = XDocument.Load(Server.MapPath("file.xml")); IEnumerable<XElement> items = from item in doc.Descendants("item") orderby Convert.ToDateTime(item.Attribute("lastChanges").Value) descending where item.Attribute("x").Value == 1 select item; Repeater1.DataSource = items; Repeater1.DataBind(); Xml file looks like this: <root> <items> <item id="1" lastChanges="15-05-2010" x="0" /> <item id="2" lastChanges="16-05-2010" x="1" /> <item id="3" lastChanges="17-05-2010" x="1" /> </items> </root>

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• php foreach getting values from an array

  - by sea_1987

  I am having trouble accessing the values in an array, the array looks like this, Array ( [0] => Array ( [id] => 1661 [code] => 849651318 [job_status] => 4 [looking_for] => Lorem ipsum [keywords_education] => Derby University [sector_id_csv] => 10,21,9,22,26 [last_job_title_1] => Programmer [last_job_employer_1] => HBOS [city] => Bury [expected_salary_level] => LEVEL_2 [education_level] => COLLEGE [job_looking_for] => [is_contract] => Y [is_permanent] => N [is_temporary] => Y ) ) Array ( [0] => Array ( [id] => 402 [code] => 849650059 [job_status] => 3 [looking_for] => Lorem ipsum [keywords_education] => Paris College [sector_id_csv] => 27,22,19,21,12 [last_job_title_1] => Programmer [last_job_employer_1] => HSBC [city] => Bury [expected_salary_level] => LEVEL_2 [education_level] => COLLEGE [job_looking_for] => [is_contract] => N [is_permanent] => Y [is_temporary] => Y ) ) Array ( [0] => Array ( [id] => 1653 [code] => 849651310 [job_status] => 3 [looking_for] => Lorem ipsum [keywords_education] => Crewe University [sector_id_csv] => 27,15,19,21,24 [last_job_title_1] => Programmer [last_job_employer_1] => ICI [city] => Bury [expected_salary_level] => LEVEL_2 [education_level] => UNIVERSITY [job_looking_for] => [is_contract] => N [is_permanent] => Y [is_temporary] => Y ) ) I am trying to get the values out, I have tried doing the following, foreach ($result as $rslt) { echo $rslt->id; } I have also tried, foreach ($result as $rslt) { $rslt['id']; } But none of this works, I dont know why, can anyone help?

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• getting a "default" concrete class that implements an interface

  - by Roger Joys

  I am implementing a custom (and generic) Json.net serializer and hit a bump in the road that I could use some help on. When the deserializer is mapping to a property that is an interface, how can I best determine what sort of object to construct to deserialize to to place into the interface property. I have the following: [JsonConverter(typeof(MyCustomSerializer<foo>))] class foo { int Int1 { get; set; } IList<string> StringList {get; set; } } My serializer properly serializes this object, and but when it comes back in, and I try to map the json parts to to object, I have a JArray and an interface. I am currently instantiating anything enumerable like List as theList = Activator.CreateInstance(property.PropertyType); This works create to work with in the deserialization process, but when the property is IList, I get runtime complaints (obviously) about not being able to instantiate an interface. So how would I know what type of concrete class to create in a case like this? Thank you

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• Getting line by line in Apple Script from Address Books Note Field

  - by Axwack

  I have two lines in my address book's note field Test 1 Test 2 I would like to get each line as a separate value or get the last line from the notes field. I tried doing it this way: tell application "Address Book" set AppleScript's text item delimiters to "space" get the note of person in group "Test Group" end tell but the result is {"Test 1 Test 2"} I'm looking for : {"Test1","Test2"} What am I doing incorrect?

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• Java 8 Stream, getting head and tail

  - by lyomi

  Java 8 introduced a Stream class that resembles Scala's Stream, a powerful lazy construct using which it is possible to do something like this very concisely: def from(n: Int): Stream[Int] = n #:: from(n+1) def sieve(s: Stream[Int]): Stream[Int] = { s.head #:: sieve(s.tail filter (_ % s.head != 0)) } val primes = sieve(from(2)) primes takeWhile(_ < 1000) print // prints all primes less than 1000 I wondered if it is possible to do this in Java 8, so I wrote something like this: IntStream from(int n) { return IntStream.iterate(n, m -> m + 1); } IntStream sieve(IntStream s) { int head = s.findFirst().getAsInt(); return IntStream.concat(IntStream.of(head), sieve(s.skip(1).filter(n -> n % head != 0))); } IntStream primes = sieve(from(2)); PrimitiveIterator.OfInt it = primes.iterator(); for (int prime = it.nextInt(); prime < 1000; prime = it.nextInt()) { System.out.println(prime); } Fairly simple, but it produces java.lang.IllegalStateException: stream has already been operated upon or closed because both findFirst() and skip() is a terminal operation on Stream which can be done only once. I don't really have to use up the stream twice since all I need is the first number in the stream and the rest as another stream, i.e. equivalent of Scala's Stream.head and Stream.tail. Is there a method in Java 8 Stream that I can achieve this? Thanks.

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