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  • Rails Tableless Model

    - by mplacona
    I'm creating a tableless Rails model, and am a bit stuck on how I should use it. Basically I'm trying to create a little application using Feedzirra that scans a RSS feed every X seconds, and then sends me an email with only the updates. I'm actually trying to use it as an activerecord model, and although I can get it to work, it doesn't seem to "hold" data as expected. As an example, I have an initializer method that parses the feed for the first time. On the next requests, I would like to simply call the get_updates method, which according to feedzirra, is the existing object (created during the initialize) that gets updated with only the differences. I'm finding it really hard to understand how this all works, as the object created on the initialize method doesn't seem to persist across all the methods on the model. My code looks something like: def initialize feed parse here end def get_updates feedzirra update passing the feed object here end Not sure if this is the right way of doing it, but it all seems a bit confusing and not very clear. I could be over or under-doing here, but I'd like your opinion about this approach. Thanks in advance

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  • Easy way to lock a file on a remote machine (windows)?

    - by roufamatic
    I've tracked down an error in my logs, and am trying to reproduce it. My theory is that a file sometimes gets locked in a specific folder, and when the application (ASP.NET) tries to delete that folder it hangs. I don't have the application running on my own machine so I'm debugging this on a remote server. But for the life of me, I can't seem to figure out a way to lock a file that prevents it from being deleted by the process. My first thought was to map the network path to a local drive and just leave a command prompt open to that folder. Locally that always fouls up my folder deletes, but apparently SMB is a bit more robust and doesn't grant me a lock. After that I created an infinte loop vbscript in the folder and executed it remotely. The file was deleted out from underneath the executing code. Man! I then tried creating a file on the server in that folder and removing all permissions. That didn't do the trick. I don't have access to the IIS settings so perhaps it's running under a privileged system account. So: what's a program that you know is free and I can quickly use to create an exclusive lock on a file so I can test my delete theory? Like a really, really bad Notepad clone or something. :-)

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  • Group / User based security. Table / SQL question

    - by Brett
    Hi, I'm setting up a group / user based security system. I have 4 tables as follows: user groups group_user_mappings acl where acl is the mapping between an item_id and either a group or a user. The way I've done the acl table, I have 3 columns of note (actually 4th one as an auto-id, but that is irrelevant) col 1 item_id (item to access) col 3 user_id (user that is allowed to access) col 3 group_id (group that is allowed to access) So for example item1, peter, , item2, , group1 item3, jane, , so either the acl will give access to a user or a group. Any one line in the ACL table with either have an item - user mapping, or an item group. If I want to have a query that returns all objects a user has access to, I think I need to have a SQL query with a UNION, because I need 2 separate queries that join like.. item - acl - group - user AND item - acl - user This I guess will work OK. Is this how its normally done? Am I doing this the right way? Seems a little messy. I was thinking I could get around it by creating a single user group for each person, so I only ever deal with groups in my SQL, but this seems a little messy as well..

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  • Ninject: Shared DI/IoC container

    - by joblot
    Hi I want to share the container across various layers in my application. I started creating a static class which initialises the container and register types in the container. public class GeneralDIModule : NinjectModule { public override void Load() { Bind().To().InSingletonScope(); } } public abstract class IoC { private static IKernel _container; public static void Initialize() { _container = new StandardKernel(new GeneralDIModule(), new ViewModelDIModule()); } public static T Get<T>() { return _container.Get<T>(); } } I noticed there is a Resolve method as well. What is the difference between Resolve and Get? In my unit tests I don’t always want every registered type in my container. Is there a way of initializing an empty container and then register types I need. I’ll be mocking types as well in unit test so I’ll have to register them as well. There is an Inject method, but it says lifecycle of instance is not managed? Could someone please set me in right way? How can I register, unregister objects and reset the container. Thanks

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  • How can I make an event created through Google Calendar's API send an invitation email?

    - by Cebjyre
    I'm trying to create an event through the API and it is mostly working, with the exception that while the new events are being created in the invitees calendars, no emails are being sent. Creating the event from the web interface is pushing the event through, as well as sending the email (except one account that doesn't get any notifications at all, but that's not relevant to my current problem). The event I am trying to push in is: <entry xmlns='http://www.w3.org/2005/Atom' xmlns:gd='http://schemas.google.com/g/2005'> <category scheme='http://schemas.google.com/g/2005#kind' term='http://schemas.google.com/g/2005#event'></category> <title type='text'>test event</title> <content type='text'>content.</content> <gd:transparency value='http://schemas.google.com/g/2005#event.opaque'> </gd:transparency> <gd:eventStatus value='http://schemas.google.com/g/2005#event.confirmed'> </gd:eventStatus> <gd:where valueString='somewhere'></gd:where> <gd:who email="[redacted]" rel='http://schemas.google.com/g/2005#event.attendee' valueString='Me'><gd:attendeeStatus value='http://schemas.google.com/g/2005#event.invited'/></gd:who> <gd:who email="[redacted again]" rel='http://schemas.google.com/g/2005#event.organizer' valueString='Also Me'><gd:attendeeStatus value='http://schemas.google.com/g/2005#event.accepted'/></gd:who> <gd:when startTime='2010-05-18T15:30:00.000+10:00' endTime='2010-05-18T16:00:00.000+10:00'></gd:when> </entry> And when I request event lists I can't see any large difference between events created through the API and through the web interface.

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  • Powershell scripts to backup SQL, SVN

    - by bszom
    I'm trying to use PowerShell to create some backups, and then to copy these to a web folder (or, in other words, upload them to a WebDAV share). At first I thought I'd do the WebDAV stuff from within PowerShell, but it seems this still requires a fair amount of "manual labour", ie: constructing HTTP requests. I then settled for creating a web folder from the script and letting Windows handle the WebDAV stuff. It seems that all it takes to create a web folder is to create a standard shortcut, as described here. What I can't figure out is how to actually copy files to the shortcut's target..? Maybe I'm going about this the wrong way. It would be ideal if I could somehow encrypt the credentials for the WebDAV in the script, then have it create the web folder, shunt over the files, and delete the web folder again. Or even better, not use a web folder at all. Third option would be to just create the web folder manually and leave it there, though I'd rather not. Any ideas/pointers/tips? :)

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  • ARM Assembly - Converting Endianness

    - by SoulBeaver
    Hello people! This is currently a homework project that me and my teammate are stuck on. We haven't been given much of an introduction into Assembly, and this is supposed to be our first homework exercise. The task is to create a program that converts 0xAABBCCDD into 0xDDCCBBAA. I'm not looking for an answer, as that would defeat the purpose, but we are getting severely frustrated over the difficulty of this stupid thing. We think we have a good start in creating a viable solution, but we just cannot come up with the rest of the program. First, we mask every single tupel (aa), (bb), (cc), (dd) into a different register: LDR R0, LittleEndian // 0xAABBCCDD AND R1, R0, #0xFF000000 // 0xAA AND R2, R0, #0x00FF0000 // 0xBB AND R3, R0, #0x0000FF00 // 0xCC AND R4, R0, #0x000000FF // 0xDD Then we try to re-align them into the R0 register, but hell if we could come up with a good solution... Our best effort came from: ORR R0, R1, LSL #24 ORR R0, R2, LSL #8 ORR R0, R3, LSR #8 ORR R0, R4, LSR #24 which produced 0xBBBBCCDD for some odd reason; we really don't know. Any hints would be greatly appreciated. Again, we are asking for help, but not for a solution. Cheers!

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  • Matplotlib autodatelocator custom date formatting?

    - by jawonlee
    I'm using Matplotlib to dynamically generate .png charts from a database. The user may set as the x-axis any given range of datetimes, and I need to account for all of it. While Matplotlib has the dates.AutoDateLocator(), I want the datetime format printed on the chart to be context-specific - e.g. if the user is charting from 3 p.m. to 5 p.m., the year/month/day information doesn't need to be displayed. Right now, I'm manually creating Locator and Formatter objects thusly: def get_ticks(start, end): from datetime import timedelta as td delta = end - start if delta <= td(minutes=10): loc = mdates.MinuteLocator() fmt = mdates.DateFormatter('%I:%M %p') elif delta <= td(minutes=30): loc = mdates.MinuteLocator(byminute=range(0,60,5)) fmt = mdates.DateFormatter('%I:%M %p') elif delta <= td(hours=1): loc = mdates.MinuteLocator(byminute=range(0,60,15)) fmt = mdates.DateFormatter('%I:%M %p') elif delta <= td(hours=6): loc = mdates.HourLocator() fmt = mdates.DateFormatter('%I:%M %p') elif delta <= td(days=1): loc = mdates.HourLocator(byhour=range(0,24,3)) fmt = mdates.DateFormatter('%I:%M %p') elif delta <= td(days=3): loc = mdates.HourLocator(byhour=range(0,24,6)) fmt = mdates.DateFormatter('%I:%M %p') elif delta <= td(weeks=2): loc = mdates.DayLocator() fmt = mdates.DateFormatter('%b %d') elif delta <= td(weeks=12): loc = mdates.WeekdayLocator() fmt = mdates.DateFormatter('%b %d') elif delta <= td(weeks=52): loc = mdates.MonthLocator() fmt = mdates.DateFormatter('%b') else: loc = mdates.MonthLocator(interval=3) fmt = mdates.DateFormatter('%b %Y') return loc,fmt Is there a better way of doing this?

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  • Disadvantages of MySQL Row Locking

    - by Nyxynyx
    I am using row locking (transactions) in MySQL for creating a job queue. Engine used is InnoDB. SQL Query START TRANSACTION; SELECT * FROM mytable WHERE status IS NULL ORDER BY timestamp DESC LIMIT 1 FOR UPDATE; UPDATE mytable SET status = 1; COMMIT; According to this webpage, The problem with SELECT FOR UPDATE is that it usually creates a single synchronization point for all of the worker processes, and you see a lot of processes waiting for the locks to be released with COMMIT. Question: Does this mean that when the first query is executed, which takes some time to finish the transaction before, when the second similar query occurs before the first transaction is committed, it will have to wait for it to finish before the query is executed? If this is true, then I do not understand why the row locking of a single row (which I assume) will affect the next transaction query that would not require reading that locked row? Additionally, can this problem be solved (and still achieve the effect row locking does for a job queue) by doing a UPDATE instead of the transaction? UPDATE mytable SET status = 1 WHERE status IS NULL ORDER BY timestamp DESC LIMIT 1

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  • Creation of Objects: Constructors or Static Factory Methods

    - by Rachel
    I am going through Effective Java and some of my things which I consider as standard are not suggested by the book, for instance creation of object, I was under the impression that constructors are the best way of doing it and books says we should make use of static factory methods, I am not able to few some advantages and so disadvantages and so am asking this question, here are the benefits of using it. Advantages: One advantage of static factory methods is that, unlike constructors, they have names. A second advantage of static factory methods is that, unlike constructors, they are not required to create a new object each time they’re invoked. A third advantage of static factory methods is that, unlike constructors, they can return an object of any subtype of their return type. A fourth advantage of static factory methods is that they reduce the verbosity of creating parameterized type instances. I am not able to understand this advantage and would appreciate if someone can explain this point Disadvantages: The main disadvantage of providing only static factory methods is that classes without public or protected constructors cannot be subclassed. A second disadvantage of static factory methods is that they are not readily distinguishable from other static methods.I am not getting this point and so would really appreciate some explanation. Reference: Effective Java, Joshua Bloch, Edition 2, pg: 5-10 Also, How to decide to use whether to go for Constructor or Static Factory Method for Object Creation ?

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  • Getting unhandled exception when DataTemplate is created dynamically using Silverlight 3.0

    - by Bhaskar
    Requirement is to create a reusable multi-select combobox custom control. To accomplish this, I am creating the DataTemplate dynamically through code and set the combobox ItemTemplate. I am able to load the datatemplate dynamically and set the ItemTemplate, but getting unhandled exception (code: 7054) when combobox is selected. Here is the code Class MultiSelCombBox: ComboBox { public override void OnApplyTemplate() { base.OnApplyTemplate(); CreateTemplate(); } void CreateTemplate() { DataTemplate dt = null; if (CreateItemTemplate) { if (string.IsNullOrEmpty(CheckBoxBind)) { dt = XamlReader.Load(@"<DataTemplate xmlns='http://schemas.microsoft.com/winfx/2006/xaml/presentation' xmlns:x='http://schemas.microsoft.com/winfx/2006/xaml' x:Name=""DropDownTemplate""><Grid xmlns='http://schemas.microsoft.com/winfx/2006/xaml/presentation' xmlns:x='http://schemas.microsoft.com/winfx/2006/xaml' x:Name=""CheckboxGrid""><TextBox xmlns='http://schemas.microsoft.com/winfx/2006/xaml/presentation' xmlns:x='http://schemas.microsoft.com/winfx/2006/xaml' x:Name=""test"" xml:space=""preserve"" Text='{Binding " + TextContent + "}'/></Grid></DataTemplate>") as DataTemplate; this.ItemTemplate = dt; } } } //Other code goes here }} what am i doing wrong? suggestion?

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  • Reference - What does this error mean in PHP?

    - by hakre
    On Stackoverflow you can see a lot of questions popping up about errors. Some users do not even know that error messages exists, others are asking about code that gives an error message but they do not understand the error message. If the error message is common, many questions about the same kind of error appears, but it is hard to find existing Q&A about the topic. Please add "your favorite" error message, one per answer, a short description what it means (even if it is only highlighting terms to their manual page) and a listing of existing Q&A that are of value. This will create a list. The question is a community wiki, so you are not answering for reputation but for creating a reference list for new users. It's based on error messages. Compare with the existing Reference - What does this symbol mean in PHP? question, which works pretty well. What are common errors in PHP and what are their Solutions. Index of Errors Just starting, but there are already some: Warning: Cannot modify header information - headers already sent Warning: mysql_fetch_array() expects parameter 1 to be resource, boolean given in ... on line Parse error: syntax error, unexpected T_XXX in YYY on line ZZZ Fatal Error: Call to a member function ... on a non-object

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  • How to stream pdf document from servlet?

    - by Kumar
    Hi,I am creating pdf document using jasper report and i need to stream that pdf document from servlet.Can anyone help me where i did mistake.This is the code snippet which i am using in my application. ServletOutputStream servletOutputStream = response.getOutputStream(); String fileName="test.pdf"; response.setContentType("application/pdf"); response.setHeader("Content-Disposition","attachment; filename=\"" + fileName + "\""); response.setHeader("Cache-Control", "no-cache"); try { Map parameters = new HashMap(); parameters.put("SUBREPORT_DIR", JasperReportFilepath); parameters.put("TestId", testID); JasperPrint jprint=JasperFillManager.fillReport(filePath, parameters, conn); byte[] output=JasperExportManager.exportReportToPdf(jprint); System.out.println("Size====>"+output.length); servletOutputStream.write(output); servletOutputStream.flush(); servletOutputStream.close(); System.out.println("===============>Streaming perfectly"); } catch(Exception e) { System.out.println("===============>+JasperException"+e.getMessage()); } and i could not get any error message also.Everything is working fine but document is not streaming. Please help me to sort out the problem.

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  • Implementing IXmlSerializable on a generated class that has XmlTypeAttribute

    - by Josh
    Basically, the initial problem is I need to make a boolean value serialize as 0 or 1. The solution I found was to implement IXmlSerializable, which I did. Unfortunately the class I'm trying to serialize is generated code off a schema and has an XmlTypeAttribute on it. When I try to (de)serialize the object with the XmlSerializer created in the usual manner ( new XmlSerializer(type)) it throws this exception: System.InvalidOperationException: Only XmlRoot attribute may be specified for the type ______ Please use XmlSchemaProviderAttribute to specify schema type. Two options come to mind immediatly: 1) remove the attribute in the generated code. This change would have to be made every time the code was re-generated. 2) Use an XmlAttributeOverrides object when creating the serializer to remove the attribute. This would require the rest of the code base to "know" that it needs to override that attribute. Also, the exception thrown gives absolutly no clue as to what needs to be done to fix it. Both options kinda stink. Is there a third option?

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  • OpenAL not playing on Max OS X 10.6

    - by Grimless
    I've been working on getting a basic audio engine running on my Mac using OpenAL. It seems relatively straightforward after working with OpenGL for a while. However, despite the fact that I believe I have everything in place, my sound will not play. Here is the order of things I am doing: //Creating a new device ALCdevice* device = alcOpenDevice(NULL); //Create a new context with the device ALCcontext* context = alcCreateContext(device, NULL); //Make that context current alcMakeContextCurrent(context); //Do lots of loading stuff to bring in an AIFF... voodooAIFF = myAIFFLoader("name"); //Then use that data ALuint buf; alGenBuffers(1, &buf); //Check for errors, but none happen... //Bind buffer data. alBufferData(buf, voodooAIFF.format, voodooAIFF.data, voodooAIFF.sizeInBytes, voodooAIFF.frequency); //Check for errors, none here either... //Create Source ALuint src; alGenSources(1, &src); //Error check again, no errors. //Bind source to buffer alSourcei(src, AL_BUFFER, buf); //Set reference distance alSourcei(sourceID, AL_REFERENCE_DISTANCE, 1); //Set source attributes including gain and pitch to 1 (direction set to 0,0,0) //Check for errors, nothing... //Set up listener attributes. //Check for errors, no errors. //Begin playing. alSourcePlay(src); Observe silence... Any insight, what steps am I missing here?

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  • Adding an ASP.NET Web User Control to a Control Dynamically

    - by RandomBen
    I have a simple ASP.NET Web User Control. It looks like this: <%@ Control Language="C#" AutoEventWireup="true" CodeBehind="NewsArticle.ascx.cs" Inherits="Website.Controls.NewsArticle" %> <div> <asp:Literal ID="ltlBody" runat="server" /> </div> My code behind looks like this: namespace Website.Controls { public partial class NewsArticle : System.Web.UI.UserControl { public String bodyText { //get { return ltlBody.Text; } set { ltlBody.Text = value; } } } } On a .aspx page I have <asp:Panel ID="pNews" runat="server" /> In the code behind I have: foreach (vwNews news in newsQuery) { NewsArticle article = new NewsArticle(); aticle.bodyText = news.Body; pNews.Controls.Add(article); } Every time I run this code the newsQuery is populated correctly and I get to the line aticle.bodyText = news.Body; and then I received the error article.bodyText threw an exception of type 'System.NullReferenceException' I am not sure what is causing this error message or how to fix it. I would think that there should not be an issue. I tried creating a constructor for my Web User Control so that it would give default values to my properties but that didn't work. Any idea how to make this work? It doesn't seem like it should be that

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  • C# class can not disguise to be another class because GetType method cannot be override

    - by zinking
    there is a statement in the CLR via C# saying in C#, one class cannot disguise to be another, because GetType is virutal and thus it cannot be override but I think in C# we can still hide the parent implementation of GetType. I must missed something if I hide the base GetType implementation then I can disguise my class to be another class, is that correct? The key here is not whether GetType is virutal or not, the question is can we disguise one class to be another in C# Following is the NO.4 answer from the possible duplicate, so My question is more on this. is this kind of disguise possible, if so, how can we say that we can prevent class type disguise in C# ? regardless of the GetType is virtual or not While its true that you cannot override the object.GetType() method, you can use "new" to overload it completely, thereby spoofing another known type. This is interesting, however, I haven't figured out how to create an instance of the "Type" object from scratch, so the example below pretends to be another type. public class NotAString { private string m_RealString = string.Empty; public new Type GetType() { return m_RealString.GetType(); } } After creating an instance of this, (new NotAString()).GetType(), will indeed return the type for a string. share|edit|flag answered Mar 15 at 18:39 Dr Snooze 213 By almost anything that looks at GetType has an instance of object, or at the very least some base type that they control or can reason about. If you already have an instance of the most derived type then there is no need to call GetType on it. The point is as long as someone uses GetType on an object they can be sure it's the system's implementation, not any other custom definition. – Servy Mar 15 at 18:54 add comment

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  • Ideal directory structure for web application

    - by rno
    I'm about to create a user based website and will have to store photo, docs and other data for each user. If I take a silly number like 1 000 000 000 users, I believe than one folder with 1 000 000 000 won't be the fastest thing in the world! So I was thinking of creating something like 1st level : [a-z] 2nd level : [a-z] 3rd level : [a-z] Therefor bobby will be in /b/o/b/by But this also mean that it won't be spread equaly, because there will be very few user starting with a z and many more with a m,s,l ... so I was thinking of using a user id such as "000000000001", "000000000001" etc... 1st level : [000-999] 2nd level : [000-999] 3rd level : [000-999] therefore data of the user 000000000001 will be store in /data/000/000/000/001 then I will be sure to have a maximum of 1000 folder in each level. What do you guys think about it, what I should do or not do ? The server will be running Centos 5.4 with EXT3 on raid 1, if the I/O get's too bad i will probably go for a raid 10.

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  • Get Classic ASP variale from posted JSON

    - by Will
    I'm trying to post JSON via AJAX to a Classic ASP page, which retrieves the value, checks a database and returns JSON to the original page. I can post JSON via AJAX I can return JSON from ASP I can't retrieve the posted JSON into an ASP variable POST you use Request.Form, GET you use Request.Querystring......... what do I use for JSON? I have JSON libraries but they only show creating a string in the ASP script and then parsing that. I need to parse JSON from when being passed an external variable. Javascipt var thing = $(this).val(); $.ajax({ type: "POST", url: '/ajax/check_username.asp', data: "{'userName':'" + thing + "'}", contentType: "application/json; charset=utf-8", dataType: "json", cache: false, async: false, success: function() { alert('success'); }); ASP file (check_username.asp) Response.ContentType = "application/json" sEmail = request.form() -- THE PROBLEM Set oRS = Server.CreateObject("ADODB.Recordset") SQL = "SELECT SYSUserID FROM WCE_UK.dbo.t_SYS_User WHERE Username='"&sEmail&"'" oRS.Open SQL, oConn if not oRS.EOF then sStatus = (new JSON).toJSON("username", true, false) else sStatus = (new JSON).toJSON("username", false, false) end if response.write sStatus

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  • Visibility of reintroduced constructor

    - by avenmore
    I have reintroduced the form constructor in a base form, but if I override the original constructor in a descendant form, the reintroduced constructor is no longer visible. type TfrmA = class(TForm) private FWndParent: HWnd; public constructor Create(AOwner: TComponent; const AWndParent: Hwnd); reintroduce; overload; virtual; end; constructor TfrmA.Create(AOwner: TComponent; const AWndParent: Hwnd); begin FWndParent := AWndParent; inherited Create(AOwner); end; type TfrmB = class(TfrmA) private public end; type TfrmC = class(TfrmB) private public constructor Create(AOwner: TComponent); override; end; constructor TfrmC.Create(AOwner: TComponent); begin inherited Create(AOwner); end; When creating: frmA := TfrmA.Create(nil, 0); frmB := TfrmB.Create(nil, 0); frmC := TfrmC.Create(nil, 0); // Compiler error My work-around is to override the reintroduced constructor or to declare the original constructor overloaded, but I'd like to understand the reason for this behavior. type TfrmA = class(TForm) private FWndParent: HWnd; public constructor Create(AOwner: TComponent); overload; override; constructor Create(AOwner: TComponent; const AWndParent: Hwnd); reintroduce; overload; virtual; end; type TfrmC = class(TfrmB) private public constructor Create(AOwner: TComponent; const AWndParent: Hwnd); override; end;

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  • drupal themes: .info file: how do I add more than 1 css file / js file to my theme?

    - by egarcia
    I'm creating a new Drupal theme. Until now, I only needed to include a single css file and a single js file. So my theme.info file had something like this: stylesheets[all][] = css/style.css scripts[] = js/script.js Now I must include jquery and jquery-ui in order to use a calendar date. These come with 2 new javascript files, and 1 additonal css file that I must add to the site. The calendar input form is going to be used in all pages (on a side block) so it is ok for me to load the extra css/javascript on all pages. I think the easiest thing would be to reference them on the .info file itself. At first I tried to just put them there with separate spaces: stylesheets[all][] = css/style.css css/ui-lightness/jquery-ui-1.8.1.custom.css scripts[] = js/jquery-1.4.2.min.js js/jquery-ui-1.8.1.custom.min.js js/reservations.js I emptied drupal's cache and... none of them loaded. I then tried separating each file with a comma, and flushing the cache again. Same result. I've browsed some drupal pages, but could not find how to add several javascript/css files on one theme (they always seem to add just 1 of each). So, how do I include several css/javascript files on the .info file?

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  • How is a functional programming-based javascript app laid out?

    - by user321521
    I've been working with node.js for awhile on a chat app (I know, very original, but I figured it'd be a good learning project). Underscore.js provides a lot of functional programming concepts which look interesting, so I'd like to understand how a functional program in javascript would be setup. From my understanding of functional programming (which may be wrong), the whole idea is to avoid side effects, which are basically having a function which updates another variable outside of the function so something like var external; function foo() { external = 'bar'; } foo(); would be creating a side effect, correct? So as a general rule, you want to avoid disturbing variables in the global scope. Ok, so how does that work when you're dealing with objects and what not? For example, a lot of times, I'll have a constructor and an init method that initializes the object, like so: var Foo = function(initVars) { this.init(initVars); } Foo.prototype.init = function(initVars) { this.bar1 = initVars['bar1']; this.bar2 = initVars['bar2']; //.... } var myFoo = new Foo({'bar1': '1', 'bar2': '2'}); So my init method is intentionally causing side effects, but what would be a functional way to handle the same sort of situation? Also, if anyone could point me to either a python or javascript source code of a program that tries to be as functional as possible, that would also be much appreciated. I feel like I'm close to "getting it", but I'm just not quite there. Mainly I'm interested in how functional programming works with traditional OOP classes concept (or does away with it for something different if that's the case).

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  • How to bind to another event after ajax call in jquery

    - by robert
    Hi, I'm creating a graph using flot javascript library. I have enabled clickable event and the div is binded to plotclick event. So, when a datapoint is clicked, an ajax call is made and the result is used to replace the current div. After this i need to bind the div to a new event. I tried to call bind, but it is still bound to old callback. When i call unbind and bind, the new callback is not called. var handleTeacherClick = function( event, pos, item ) { if( typeof item != "undefined" && item ) { var user_id = jQuery( 'input[name="id' + item.datapoint[0] + '"]' ).val(); jQuery.ajax({ type: 'POST', url: BASEPATH + 'index.php/ajax/home/latest', data: { "user_id": user_id }, dataType: 'json', success: function ( result ) { jQuery.plot(jQuery('#stats_prog'), result.progress_data, result.progress_options); jQuery.plot(jQuery('#stats_perf'), result.performance_data, result.performance_options); jQuery('.stats_title'). html('<span class="stats_title">'+ ' >> Chapter '+Math.ceil(item.datapoint[0])+'</span>'); jQuery('#stats_prog')./*unbind("plotclick").*/ bind('plotclick', statClickHandler ); jQuery('#stats_perf')./*unbind("plotclick"). */ bind( 'plotclick', statClickHandler ); }, }); } }

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  • How to specialize a type parameterized argument to multiple different types for in Scala?

    - by jmount
    I need a back-check (please). In an article ( http://www.win-vector.com/blog/2010/06/automatic-differentiation-with-scala/ ) I just wrote I stated that it is my belief in Scala that you can not specify a function that takes an argument that is itself a function with an unbound type parameter. What I mean is you can write: def g(f:Array[Double]=>Double,Array[Double]):Double but you can not write something like: def g(f[Y]:Array[Y]=>Double,Array[Double]):Double because Y is not known. The intended use is that inside g() I will specialize fY to multiple different types at different times. You can write: def g[Y](f:Array[Y]=>Double,Array[Double]):Double but then f() is of a single type per call to g() (which is exactly what we do not want). However, you can get all of the equivalent functionality by using a trait extension instead insisting on passing around a function. What I advocated in my article was: 1) Creating a trait that imitates the structure of Scala's Function1 trait. Something like: abstract trait VectorFN { def apply[Y](x:Array[Y]):Y } 2) declaring def g(f:VectorFN,Double):Double (using the trait is the type). This works (people here on StackOverflow helped me find it, and I am happy with it)- but am I mis-representing Scala by missing an even better solution?

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  • Sudoku Recursion Issue (Java)

    - by SkylineAddict
    I'm having an issue with creating a random Sudoku grid. I tried modifying a recursive pattern that I used to solve the puzzle. The puzzle itself is a two dimensional integer array. This is what I have (By the way, the method doesn't only randomize the first row. I had an idea to randomize the first row, then just decided to do the whole grid): public boolean randomizeFirstRow(int row, int col){ Random rGen = new Random(); if(row == 9){ return true; } else{ boolean res; for(int ndx = rGen.nextInt() + 1; ndx <= 9;){ //Input values into the boxes sGrid[row][col] = ndx; //Then test to see if the value is valid if(this.isRowValid(row, sGrid) && this.isColumnValid(col, sGrid) && this.isQuadrantValid(row, col, sGrid)){ // grid valid, move to the next cell if(col + 1 < 9){ res = randomizeFirstRow(row, col+1); } else{ res = randomizeFirstRow( row+1, 0); } //If the value inputed is valid, restart loop if(res == true){ return true; } } } } //If no value can be put in, set value to 0 to prevent program counting to 9 setGridValue(row, col, 0); //Return to previous method in stack return false; } This results in an ArrayIndexOutOfBoundsException with a ridiculously high or low number (+- 100,000). I've tried to see how far it goes into the method, and it never goes beyond this line: if(this.isRowValid(row, sGrid) && this.isColumnValid(col, sGrid) && this.isQuadrantValid(row, col, sGrid)) I don't understand how the array index goes so high. Can anyone help me out?

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