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• Conflict with @Html.LabelFor and W3C Validator?

  - by Tyler

  I have a model that I am using to present an index of a model from a database and have given a display name to some of the rows that may need spaces in them, (I.e. "weekstarting" in a db would be given a display name of "Week Starting"). So I set the display name for my model like this: [DisplayName("Week Starting")] public DateTime WeekStarting { get; set; } and then in the table headers for my table I use the following line of code to display the field name using its given display name: @Html.LabelFor(x => x.First().WeekStarting) The above all works fine. But I am using the W3C validator and it is giving me the following error for the example I have given: The for attribute of the label element must refer to a form control. Forgive me if it is obvious but what am I doing wrong here? I am not using a form I am simply displaying an index of items in a table. I have tried to look for an answer and saw someone suggest that the form controls being referred to need ids (even though I'm not using a form) but this would not be applicable in this instance because if I tried to set an id in the index it would be duplicated with each item in the index: foreach (var item in Model.Tbms) { <tr><td>@item.value</td><tr>.... would be repeated for each item, and also unsure where I would put the id in any case, the td? } Or is there a better way to label the field header, with my preferred display name in the first place? I guess I could just swap @Html.LabelFor... for Hard code field name but do I have to?

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• rc.local on ubuntu on ec2 will not work

  - by Tampa

  Below are the contents of my rc.local file. When I run sudo /etc/rc.local it works fine. When I boot up and instance. I expect monit to be installed but it is not. I am at a total loss. I usually use rc.local but this is rather confunsing. #!/bin/sh -e # # rc.local # # This script is executed at the end of each multiuser runlevel. # Make sure that the script will "exit 0" on success or any other # value on error. # # In order to enable or disable this script just change the execution # bits. # # By default this script does nothing. apt-get -y install monit /etc/init.d/monit stop cd /home/ubuntu/workspace/rtbopsConfig/ git fetch git checkout origin/master rtb_ec2_boot/ec2_boot.py git checkout origin/master config/ cp /home/ubuntu/workspace/rtbopsConfig/config/monit/redis/monitrc /etc/monit/ /usr/bin/python /home/ubuntu/workspace/rtbopsConfig/rtb_ec2_boot/ec2_boot.py >> /home/ubuntu/workspace/ec2_boot.txt 2>&1 /etc/init.d/monit start chkconfig monit on exit 0

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• Elements of a Java Object Array are created but without correct names

  - by Greenhouse Gases

  Hi all Im having rather an annoying problem. I have a class called Person and a class called Event which serve to create objects to be used for competitors that compete in a certain event. When I add a competitor thats fine and the GUI list updates accordingly, however when I add an event the element in the array does not take on the value of the instance variable name in the class Event and so the GUI does not show the event name, though it is being added in the array correctly. How can I make it so that the event object in each element of the listOfEvents array (which is an array of event objects) has the name of the event. I should add this is for university though this isnt the part for which we will be assessed, it is somethign i have come across and due to not being able to see the code for the GUI, I've hit the proverbial brick wall. I wont include the whole load of code Ive been writing but hopefully my description and snippets below will suffice. Any advice I would appreciate greatly. No doubt I have overlooked something simple! Many thanks. listOfEvents is declared as: Event[] listOfEvents = new Event[20]; A snippet from the Event class: public class Event { String name; Person[] participants = new Person[10]; // array of competitors for the event public Event(String name) { this.name = name; } } and its use in the addEvent method (p is a global variable): public void addEvent(String eventName) { listOfEvents[p] = new Event(eventName); p++; }

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• Loop through a set of HTML files and append text at top and bottom of each file

  - by NJTechGuy

  For instance, I have an HTML file like this : a.htm <body> Hello world! </body> I want : a.htm <html> <LINK href='style.css' rel=stylesheet type='text/css'> <body> Hello world! </body> </html> The code I have so far is : #!/bin/sh for i in `ls *.htm` do @echo off echo ***New top line*** > temp.txt type i >> temp.txt echo ***New bottom line*** >> temp.txt move /y temp.txt i done Errors : abc@bunny:~/fileAppendText$ ./loopAllFilesTest.sh ./loopAllFilesTest.sh: line 5: @echo: command not found ./loopAllFilesTest.sh: line 7: type: i: not found ./loopAllFilesTest.sh: line 9: move: command not found ./loopAllFilesTest.sh: line 5: @echo: command not found ./loopAllFilesTest.sh: line 7: type: i: not found ./loopAllFilesTest.sh: line 9: move: command not found ./loopAllFilesTest.sh: line 5: @echo: command not found ./loopAllFilesTest.sh: line 7: type: i: not found ./loopAllFilesTest.sh: line 9: move: command not found Please help. Thanks!

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• Method returns an IDisposable - Should I dispose of the result, even if it's not assigned to anythin

  - by mjd79

  This seems like a fairly straightforward question, but I couldn't find this particular use-case after some searching around. Suppose I have a simple method that, say, determines if a file is opened by some process. I can do this (not 100% correctly, but fairly well) with this: public bool IsOpen(string fileName) { try { File.Open(fileName, FileMode.Open, FileAccess.Read, FileShare.None); } catch { // if an exception is thrown, the file must be opened by some other process return true; } } (obviously this isn't the best or even correct way to determine this - File.Open throws a number of different exceptions, all with different meanings, but it works for this example) Now the File.Open call returns a FileStream, and FileStream implements IDisposable. Normally we'd want to wrap the usage of any FileStream instantiations in a using block to make sure they're disposed of properly. But what happens in the case where we don't actually assign the return value to anything? Is it still necessary to dispose of the FileStream, like so: try { using (File.Open(fileName, FileMode.Open, FileAccess.Read, FileShare.None)); { /* nop */ } } catch { return true; } Should I create a FileStream instance and dispose of that? try { using (FileStream fs = File.Open(fileName, FileMode.Open, FileAccess.Read, FileShare.None)); } ... Or are these totally unnecessary? Can we simply call File.Open and not assign it to anything (first code example), and let the GC dispose of it right away?

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• C# generics with MVVM, pulling the T out of <T>

  - by bufferz

  My Model is a generic class that contains a (for example) Value property which can be int, float, string, bool, etc. So naturally this class is represented something like Model<T>. For the sake of collections Model<T> implements the interface IModel, although IModel is itself empty of any content. My ViewModel contains and instance of Model<T> and it is passed in through ViewModel's constructor. I still want to know what T is in ViewModel, so when I expose Model to the View I know the datatype of Model's buried Value property. The class for ViewModel ends up looking like the following: class ViewModel<T> { private Model<T> _model; public ViewModel(Model<T> model) { ....blah.... } public T ModelsValue {get; set; } } This works fine, but is limited. So now I need to expose a collection of IModels with varying Ts to my View, so I'm trying to set up an ObservableCollection of new ViewModel<T>s to a changing list of IModels. The problem is, I can't figure out how to get T from Model<T> from IModel to construct ViewModel<T>(Model<T>) at runtime. In the VS2010 debugger I can mouseover any IModel object and see its full Model<int> for example at runtime so I know the data is in there. Any ideas?

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• Python NameError when attempting to use a user-defined class

  - by Michael Herold

  I'm getting a weird instance of a NameError when attempting to use a class I wrote. In a directory, I have the following file structure: dir/ ReutersParser.py test.py reut-xxx.sgm Where my custom class is defined in ReutersParser.py and I have a test script defined in test.py. The ReutersParser looks something like this: from sgmllib import SGMLParser class ReutersParser(SGMLParser): def __init__(self, verbose=0): SGMLParser.__init__(self, verbose) ... rest of parser if __name__ == '__main__': f = open('reut2-short.sgm') s = f.read() p = ReutersParser() p.parse(s) It's a parser to deal with SGML files of Reuters articles. The test works perfectly. Anyway, I'm going to use it in test.py, which looks like this: from ReutersParser import ReutersParser def main(): parser = ReutersParser() if __name__ == '__main__': main() When it gets to that parser line, I'm getting this error: Traceback (most recent call last): File "D:\Projects\Reuters\test.py", line 34, in <module> main() File "D:\Projects\Reuters\test.py", line 19, in main parser = ReutersParser() File "D:\Projects\Reuters\ReutersParser.py", line 38, in __init__ SGMLParser.__init__(self, verbose) NameError: global name 'sgmllib' is not defined For some reason, when I try to use my ReutersParser in test.py, it throws an error that says it cannot find sgmllib, which is a built-in module. I'm at my wits' end trying to figure out why the import won't work. What's causing this NameError? I've tried importing sgmllib in my test.py and that works, so I don't understand why it can't find it when trying to run the constructor for my ReutersParser.

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• Whether to put method code in a VB.Net data storage class, or put it in a separate class?

  - by Alan K

  TLDR summary: (a) Should I include (lengthy) method code in classes which may spawn multiple objects at runtime, (b) does doing so cause memory usage bloat, (c) if so should I "outsource" the code to a class that is loaded only once and have the class methods call that, or alternatively (d) does the code get loaded only once with the object definition anyway and I'm worrying about nothing? ........ I don't know whether there's a good answer to this but if there is I haven't found it yet by searching in the usual places. In my VB.Net (2010 if it matters) WinForms project I have about a dozen or so class objects in an object model. Some of these are pretty simple and do little more than act as data storage repositories. The ones further up the object model, however, have an increasing number of methods. There can be a significant number of higher level objects in use though the exact number will be runtime dependent so I can't be more precise than that. As I was writing the method code for one of the top level ones I noticed that it was starting to get quite lengthy. Memory optimisation is something of a lost art given how much memory the average PC has these days but I don't want to make my application a resource hog. So my questions for anyone who knows .Net way better than I do (of which there will be many) are: Is the code loaded into memory with each instance of the class that's created? Alternatively is it loaded only once with the definition of the class, and all derived objects just refer to that definition? (I'm not really sure how that could be possible given that, for example, event handlers can be assigned dynamically, but no harm asking.) If the answer to the first one is yes, would it be more efficient to write the code in a "utility" object which is loaded only once and called from the real class' methods? Any thoughts appreciated.

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• linux bash script: set date/time variable to auto-update (for inclusion in file names)

  - by user1859492

  Essentially, I have a standard format for file naming conventions. It breaks down to this: target_dateUTC_timeUTC_tool So, for instance, if I run tcpdump on a target of 'foo', then the file would be foo_dateUTC_timeUTC_tcpdump. Simple enough, but a pain for everyone to constantly (and consistently) enter... so I've tried to create a bash script which sets system variables like so: FILENAME=$TARGET\_$UTCTIME\_$TOOL Then, I can just call the variable at runtime, like so: tcpdump -w $FILENAME.lpc All of this works like a champ. I've got a menu-driven .sh which gives the user the options of viewing the current variables as well as setting them... file generation is a breeze. Unfortunately, by setting the date/time variable, it is locked to the value at the time of creation (naturally). I set the variable like so: UTCTIME=$(/bin/date --utc +"%Y%m%d_%H%M%Z") What I really need is either a way to create a variable which updates at runtime, or (more likely) another way to skin this cat. While scouring for solutions, I came across a similar issues... like this. But, to be honest, I'm stumped on how to marry the two approaches and create a simple, distributable solution. I can post the entire .sh if anyone cares to review (about 120 lines)

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• Custom API requirement

  - by Jonathan.Peppers

  We are currently working on an API for an existing system. It basically wraps some web-requests as an easy-to-use library that 3rd party companies should be able to use with our product. As part of the API, there is an event mechanism where the server can call back to the client via a constantly-running socket connection. To minimize load on the server, we want to only have one connection per computer. Currently there is a socket open per process, and that could eventually cause load problems if you had multiple applications using the API. So my question is: if we want to deploy our API as a single standalone assembly, what is the best way to fix our problem? A couple options we thought of: Write an out of process COM object (don't know if that works in .Net) Include a second exe file that would be required for events, it would have to single-instance itself, and open a named pipe or something to communicate through multiple processes Extract this exe file from an embedded resource and execute it None of those really seem ideal. Any better ideas?

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• Simulate stochastic bipartite network based on trait values of species - in R

  - by Scott Chamberlain

  I would like to create bipartite networks in R. For example, if you have a data.frame of two types of species (that can only interact across species, not within species), and each species has a trait value (e.g., size of mouth in the predator allows who gets to eat which prey species), how do we simulate a network based on the traits of the species (that is, two species can only interact if their traits overlap in values for instance)? UPDATE: Here is a minimal example of what I am trying to do. 1) create phylogenetic tree; 2) simulate traits on the phylogeny; 3) create networks based on species trait values. # packages install.packages(c("ape","phytools")) library(ape); library(phytools) # Make phylogenetic trees tree_predator <- rcoal(10) tree_prey <- rcoal(10) # Simulate traits on each tree trait_predator <- fastBM(tree_predator) trait_prey <- fastBM(tree_prey) # Create network of predator and prey ## This is the part I can't do yet. I want to create bipartite networks, where ## predator and prey interact based on certain crriteria. For example, predator ## species A and prey species B only interact if their body size ratio is ## greater than X.

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• How to draw mutiple rectangles using c#

  - by Nivas

  I have drawn and saved the Rectangle on the image i loaded in the picture box. How i like to draw multiple rectangles for that i tried array in the rectangle but it gives error ("Object reference not set to an instance of an object." (Null reference Exception was unhandled). enter code here private void pictureBox1_MouseDown(object sender, MouseEventArgs e) { if (mybitmap == null) { mybitmap = new Bitmap(sz.Width, sz.Height); } rect = new Rectangle(e.X, e.Y, 0, 0); this.Invalidate(); } private void pictureBox1_MouseMove(object sender, MouseEventArgs e) { if (stayToolStripMenuItem.Checked == true) { switch (e.Button) { case MouseButtons.Left: { rect = new Rectangle(rect.Left, rect.Top, e.X - rect.Left, e.Y - rect.Top); pictureBox1.Invalidate(); break; } } } } private void pictureBox1_Paint(object sender, PaintEventArgs e) { if (stayToolStripMenuItem.Checked == true) { button1.Visible = true; button2.Visible = true; if (mybitmap == null) { return; } using (g = Graphics.FromImage(mybitmap)) { using (Pen pen = new Pen(Color.Red, 2)) { //g.Clear(Color.Transparent); e.Graphics.DrawRectangle(pen, rect); label1.Top = rect.Top; label1.Left = rect.Left; label1.Width = rect.Width; label1.Height = rect.Height; if (label1.TextAlign == ContentAlignment.TopLeft) { e.Graphics.DrawString(label1.Text, label1.Font, new SolidBrush(label1.ForeColor), rect); g.DrawString(label1.Text, label1.Font, new SolidBrush(label1.ForeColor), rect); g.DrawRectangle(pen, rect); } } } } } How can i do this.....

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• What do I do about a Java program that spawned two instaces of itself?

  - by user288915

  I have a java JAR file that is triggered by a SQL server job. It's been running successfully for months. The process pulls in a structured flat file to a staging database then pushes that data into an XML file. However yesterday the process was triggered twice at the same time. I can tell from a log file that gets created, it looks like the process ran twice simultaneously. This caused a lot of issues and the XML file that it kicked out was malformed and contained duplicate nodes etc. My question is, is this a known issue with Java JVM's spawning multiple instances of itself? Or should I be looking at sql server as the culprit? I'm looking into 'socket locking' or file locking to prevent multiple instances in the future. This is the first instance of this issue that I've ever heard of. More info: The job is scheduled to run every minute. The job triggers a .bat file that contains the java.exe - jar filename.jar The java program runs, scans a directory for a file and then executes a loop to process if the file if it finds one. After it processes the file it runs another loop that kicks out XML messages. I can provide code samples if that would help. Thank you, Kevin

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• NUll exception in filling a querystring by mocing framework

  - by user564101

  There is a simple controller that a querystring is read in constructor of it. public class ProductController : Controller { parivate string productName; public ProductController() { productName = Request.QueryString["productname"]; } public ActionResult Index() { ViewData["Message"] = productName; return View(); } } Also I have a function in unit test that create an instance of this Controller and I fill the querystring by a Mock object like below. [TestClass] public class ProductControllerTest { [TestMethod] public void test() { // Arrange var querystring = new System.Collections.Specialized.NameValueCollection { { "productname", "sampleproduct"} }; var mock = new Mock<ControllerContext>(); mock.SetupGet(p => p.HttpContext.Request.QueryString).Returns(querystring); var controller = new ProductController(); controller.ControllerContext = mock.Object; // Act var result = controller.Index() as ViewResult; // Assert Assert.AreEqual("Index", result.ViewName); } } Unfortunately Request.QueryString["productname"] is null in constructor of ProductController when I run test unit. Is ther any way to fill a querystrin by a mocking and get it in constructor of a control?

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• How do I add an object to a binary tree based on the value of a member variable?

  - by Max

  How can I get a specific value from an object? I'm trying to get a value of an instance for eg. ListOfPpl newListOfPpl = new ListOfPpl(id, name, age); Object item = newListOfPpl; How can I get a value of name from an Object item?? Even if it is easy or does not interest you can anyone help me?? Edited: I was trying to build a binary tree contains the node of ListOfPpl, and need to sort it in the lexicographic. Here's my code for insertion on the node. Any clue?? public void insert(Object item){ Node current = root; Node follow = null; if(!isEmpty()){ root = new Node(item, null, null); return; }boolean left = false, right = false; while(current != null){ follow = current; left = false; right = false; //I need to compare and sort it if(item.compareTo(current.getFighter()) < 0){ current = current.getLeft(); left = true; }else { current = current.getRight(); right = true; } }if(left) follow.setLeft(new Node(item, null, null)); else follow.setRight(new Node(item, null, null)); }

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• How to: StructureMap and configuration based on runtime parameters?

  - by user981375

  In a nutshell - I want to be able to instantiate object based on runtime parameters. In this particular case there are only two parameters but the problem is that I'm facing different permutations of these parameters and it gets messy. Here is the situation: I want to get an instance of an object specific to, say, given country and then, say, specific state/province. So, considering the US, there are 50 possible combinations. In reality it's less than that but that's the max. Think of it this way, I want to find out what's the penalty for smoking pot in a given country/state, I pass this information in and I get instantiated object telling me what it is. To the code (for reference only): interface IState { string Penalty { get; } } interface ICountry { IState State { get; set; } string Name { get; } } class BasePenalty : IState { virtual public string Penalty { get { return "Slap on a wrist"; } } } class USA : ICountry { public USA(IState state) { State = state; } public IState State { get; set; } public string Name { get { return "USA"; } } } class Florida: BasePenalty { public override string Penalty { get { return "Public beheading"; } } } // and so on ... I defined other states // which have penalties other than the "Slap on a wrist" How do I configure my container that when given country and state combination it will return the penalty? I tried combinations of profile and contextual binding but that configuration was directly proportional to the number of classes I've created. I have already gone thru trouble of defining different combinations. I'd like to avoid having to do the same during container configuration. I want to inject State into the Country. Also, I'd like to return UsaBasePenalty value in case state is not specified. Is that possible? Perhaps these is something wrong with the design.

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• Declaring an object of a conditional type with a System.Type

  - by Chapso

  I am attempting to launch a specific form depending on the selected node of a treeview on the doubleclick event. The code I need to use to launch the form is a little bulky becuase I have to ensure that the form is not disposed, and that the form is not already open, before launching a new instance. I'd like to have all of this checking happen in one place at the end of the function, which means that I have to be able to pass the right form type to the code at the end. I'm trying to do this with a System.Type, but that doesn't seem to be working. Could someone point me in the right direction, please? With TreeView.SelectedNode Dim formType As Type Select Case .Text Case "Email to VPs" formType = EmailForm.GetType() Case "Revise Replacers" formType = DedicatedReplacerForm.GetType() Case "Start Email" formType = EmailForm.GetType() End Select Dim form As formType Dim form As formType Try form = CType(.Tag, formType) If Not form.IsDisposed Then form.Activate() Exit Sub End If Catch ex As NullReferenceException 'This will error out the first time it is run as the form has not yet ' been defined. End Try form = New formType form.MdiParent = Me .Tag = form CType(TreeView.SelectedNode.Tag, Form).Show() End With

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• When is a Web Service constructor called? [Java Netbeans 6.7.1 & Tomcat 6.0.18]

  - by Shaitan00

  I am migrating a Java RMI application to Java Web Service (school assignment) and I've encountered an issue... Currently my Java Server creates an instance of the Remote Object, this object has a constructor and takes a parameter (int ID) which tells it which database to load in memory - works like a charm ... Now, migrating this to Web Services is causing my a problem - first I needed to add a default constructor because it wouldn't deploy without it, and then while doing some reading all these discussions about "stateless web services" kept coming up ... For example, if I "start" my webservice with parameter(0) it would load from Databse 0 and all requests from Clients would be done using that data... I want this to only happen when I start the WebService and NOT everytime the client connects... Loading from the DB is expensive and takes time, so I want to do it once so that clients when they connect just deal with the data in memory ... This is how it works with my Java RMI .... but can this also work with Web Services? Any advice would be much appreciated. Thanks,

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• issue with tab bar view displaying a compound view

  - by ambertch

  I created a tab bar application, and I make the first tab a table. So I create a tableView controller, and go about setting the class identity of the view controller for the first tab to my tableView controller. This works fine, and I see the contents of the table filling up the whole screen. However, this is not what I actually want in the end goal - I would like a compound window having multiple views: - the aforementioned table - a custom view with data in it So what I do is create a nib for this content (call it contentNib), change the tab's class from the tableView controller to a generic UIViewController, and set the nib of that tab to this new contentNib. In this new contentNib I drag on a tableView and set File's Owner to the TableViewController. I then link the dataSource and delegate to file's owner (which is TableViewController). Surprisingly this does not work and I receive the error: **Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '*** -[UIViewController tableView:numberOfRowsInSection:]: unrecognized selector sent to instance 0x3b0f910'** This is bewildering to me since the file's owner is the TableViewController, which has been assigned to be both the dataSource and delegate. Does someone have either insight into my confusions, or a link to an example of how to have a compound view include a tableView? *update* I see this in the Apple TableView programming guide: "Note: You should use a UIViewController subclass rather than a subclass of UITableViewController to manage a table view if the view to be managed is composed of multiple subviews, one of which is a table view. The default behavior of the UITableViewController class is to make the table view fill the screen between the navigation bar and the tab bar (if either are present)." <----- I don't really get what this is telling me to do though... if someone can explain or point me to an example I'd be much appreciated!

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• Automating Excel through the PIA makes VBA go squiffy.

  - by Jon Artus

  I have absolutely no idea how to start diagnosing this, and just wondered if anyone had any suggestions. I'm generating an Excel spreadsheet by calling some Macros from a C# application, and during the generation process it somehow breaks. I've got a VBA class containing all of my logging/error-handling logic, which I instantiate using a singleton-esque accessor, shown here: Private mcAppFramework As csys_ApplicationFramework Public Function AppFramework() As csys_ApplicationFramework If mcAppFramework Is Nothing Then Set mcAppFramework = New csys_ApplicationFramework Call mcAppFramework.bInitialise End If Set AppFramework = mcAppFramework End Function The above code works fine before I've generated the spreadsheet, but afterwards fails. The problem seems to be the following line; Set mcAppFramework = New csys_ApplicationFramework which I've never seen fail before. If I add a watch to the variable being assigned here, the type shows as csys_ApplicationFramework/wksFoo, where wksFoo is a random worksheet in the same workbook. What seems to be happening is that while the variable is of the right type, rather than filling that slot with a new instance of my framework class, it's making it point to an existing worksheet instead, the equivalent of Set mcAppFramework = wksFoo which is a compiler error, as one might expect. Even more bizarrely, if I put a breakpoint on the offending line, edit the line, and then resume execution, it works. For example, I delete the word 'New' move off the line, move back, re-type 'New' and resume execution. This somehow 'fixes' the workbook and it works happily ever after, with the type of the variable in my watch window showing as csys_ApplicationFramework/csys_ApplicationFramework as I'd expect. This implies that manipulating the workbook through the PIA is somehow breaking it temporarily. All I'm doing in the PIA is opening the workbook, calling several macros using Excel.Application.Run(), and saving it again. I can post a few more details if anyone thinks that it's relevant. I don't know how VBA creates objects behind the scenes or how to debug this. I also don't know how the way the code executes can change without the code itself changing. As previously mentioned, VBA has frankly gone a bit squiffy on me... Any thoughts?

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• short-cutting equality checking in F#?

  - by John Clements

  In F#, the equality operator (=) is generally extensional, rather than intensional. That's great! Unfortunately, it appears to me that F# does not use pointer equality to short-cut these extensional comparisons. For instance, this code: type Z = MT | NMT of Z ref // create a Z: let a = ref MT // make it point to itself: a := NMT a // check to see whether it's equal to itself: printf "a = a: %A\n" (a = a) ... gives me a big fat segmentation fault[*], despite the fact that 'a' and 'a' both evaluate to the same reference. That's not so great. Other functional languages (e.g. PLT Scheme) get this right, using pointer comparisons conservatively, to return 'true' when it can be determined using a pointer comparison. So: I'll accept the fact that F#'s equality operator doesn't use short-cutting; is there some way to perform an intensional (pointer-based) equality check? The (==) operator is not defined on my types, and I'd love it if someone could tell me that it's available somehow. Or tell me that I'm wrong in my analysis of the situation: I'd love that, too... [*] That would probably be a stack overflow on Windows; there are things about Mono that I'm not that fond of...

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• How come JFrame window size in Java does not produce the size of window specified?

  - by typoknig

  Hi all, I am just messing around trying to make a game right now, but I have had this problem before too. When I specify a specific window size (1024 x 768 for instance) the window produced is just a little larger than what I specified. Very annoying. Is there a reason for this? How do I correct it so the window created is actually the size I want instead of being just a little bit bigger? Up till now I have always just gone back and manually adjusted the size a few pixels at a time until I got the result I wanted, but that is getting old. If there was even a formula I could use that would tell me how many pixels I needed to add/subtract from my my variable that would be excellent! P.S. I don't know if my OS could be a factor in this, but I am using W7X64. private int windowWidth = 1024; private int windowHeight = 768; public SomeWindow() { this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); this.setSize(windowWidth, windowHeight); this.setResizable(false); this.setLocation(0,0); this.setVisible(true); }

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• Dealloc'd Predicate crashing iPhone App!

  - by DVG

  To preface, this is a follow up to an inquiry made a few days ago: http://stackoverflow.com/questions/2981803/iphone-app-crashes-when-merging-managed-object-contexts Short Version: EXC_BAD_ACCESS is crashing my app, and zombie-mode revealed the culprit to be my predicate embedded within the fetch request embedded in my Fetched Results Controller. How does an object within an object get released without an explicit command to do so? Long Version: Application Structure Platforms View Controller - Games View Controller (Predicated upon platform selection) - Add Game View Controller When a row gets clicked on the Platforms view, it sets an instance variable in Games View for that platform, then the Games Fetched Results Controller builds a fetch request in the normal way: - (NSFetchedResultsController *)fetchedResultsController{ if (fetchedResultsController != nil) { return fetchedResultsController; } //build the fetch request for Games NSFetchRequest *request = [[NSFetchRequest alloc] init]; NSEntityDescription *entity = [NSEntityDescription entityForName:@"Game" inManagedObjectContext:context]; [request setEntity:entity]; //predicate NSPredicate *predicate = [NSPredicate predicateWithFormat:@"platform == %@", selectedPlatform]; [request setPredicate:predicate]; //sort based on name NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"name" ascending:YES]; NSArray *sortDescriptors = [[NSArray alloc] initWithObjects:sortDescriptor, nil]; [request setSortDescriptors:sortDescriptors]; //fetch and build fetched results controller NSFetchedResultsController *aFetchedResultsController = [[NSFetchedResultsController alloc] initWithFetchRequest:request managedObjectContext:context sectionNameKeyPath:nil cacheName:@"Root"]; aFetchedResultsController.delegate = self; self.fetchedResultsController = aFetchedResultsController; [sortDescriptor release]; [sortDescriptors release]; [predicate release]; [request release]; [aFetchedResultsController release]; return fetchedResultsController; } At the end of this method, the fetchedResultsController's _fetch_request - _predicate member is set to an NSComparisonPredicate object. All is well in the world. By the time - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section gets called, the _predicate is now a Zombie, which will eventually crash the application when the table attempts to update itself. I'm more or less flummoxed. I'm not releasing the fetched results controller or any of it's parts, and the only part getting dealloc'd is the predicate. Any ideas?

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• Altering sql tables based on condition

  - by Parker

  Is there any possible way to add a row of data to only some of the tables in a database? I am not sure what parameter I could use amongst the tables to compare them to each other. Any Ideas? For Example: My database has tables that are (let's say) group A tables, and tables that are group B. I want to add a row to only the group B tables while leaving the group A tables untouched. Sorry I should have been a bit more specific. The tables that need to have a row added will change. My application monitors inventory in different store locations(each table in my database represents a store). When I need to add an item to inventory(the items are rows in the tables) I don't want to have to manually add the row to all the store tables. My problem is: Not all the tables in the database represent stores. For instance one table stores the user login data. Obviously I do not want to add the new row to this table. How do I update only the tables that represent stores?

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• Entity Framework Decorator Pattern

  - by Anthony Compton

  In my line of business we have Products. These products can be modified by a user by adding Modifications to them. Modifications can do things such as alter the price and alter properties of the Product. This, to me, seems to fit the Decorator pattern perfectly. Now, envision a database in which Products exist in one table and Modifications exist in another table and the database is hooked up to my app through the Entity Framework. How would I go about getting the Product objects and the Modification objects to implement the same interface so that I could use them interchangeably? For instance, the kind of things I would like to be able to do: Given a Modification object, call .GetNumThings(), which would then return the number of things in the original object, plus or minus the number of things added by the modification. This question may be stemming from a pretty serious lack of exposure to the nitty-gritty of EF (all of my experience so far has been pretty straight-forward LOB Silverlight apps), and if that's the case, please feel free to tell me to RTFM. Thanks in advance!

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