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  • Validation.HasError attached property

    - by Nima
    Did I miss something? 1- Style <Style TargetType="{x:Type TextBox}"> <Style.Triggers> <DataTrigger Binding="{Binding Path=Validation.HasError}" Value="true"> <Setter Property="BorderBrush" Value="Blue" /> </DataTrigger> </Style.Triggers> <Setter Property="MinWidth" Value="160" /> <Setter Property="Margin" Value="0 7 0 0"/> </Style> 2 - Viewmodel implement IDataErrorInfo 3- textBox in view <TextBox x:Name="FirstName" Text="{Binding Person.FirstName, UpdateSourceTrigger=PropertyChanged, ValidatesOnDataErrors=true}"></TextBox> 3 - I use Caliburn MVVM I got " BindingExpression path error: 'Validation' property not found on 'object' ''PersonWindowViewModel' (HashCode=38783181)'. BindingExpression:Path=Validation.HasError; DataItem='PersonWindowViewModel' (HashCode=38783181); target element is 'TextBox' (Name='FirstName'); target property is 'NoTarget' (type 'Object')"S

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  • pyramid traversal resource url no attribute __name__

    - by Santana
    So I have: resources.py: def _add(obj, name, parent): obj.__name__ = name obj.__parent__ = parent return obj class Root(object): __parent__ = __name__ = None def __init__(self, request): super(Root, self).__init__() self.request = request self.collection = request.db.post def __getitem__(self, key): if u'profile' in key: return Profile(self.request) class Profile(dict): def __init__(self, request): super(Profile, self).__init__() self.__name__ = u'profile' self.__parent__ = Root self.collection = request.db.posts def __getitem__(self, name): post = Dummy(self.collection.find_one(dict(username=name))) return _add(post, name, self) and I'm using MongoDB and pyramid_mongodb views.py: @view_config(context = Profile, renderer = 'templates/mytemplate.pt') def test_view(request): return {} and in mytemplate.pt: <p tal:repeat='item request.context'> ${item} </p> I can echo what's in the database (I'm using mongodb), but when I provided a URL for each item using resource_url() <p tal:repeat='item request.context'> <a href='${request.resource_url(item)}'>${item}</a> </p> I got an error: 'dict' object has no attribute '__name__', can someone help me?

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  • Is there a way to automate MS Office applications without license?

    - by james-h-l
    I am currently writing an application that will perform automation in Excel. I have MS Office (2007) installed on my work computer and the application is working fine referencing the the Microsoft Excel 12.0 Object Lirary. The target machine has the Office installed but not registered. It is one of those preinstalled editions. Attempting to run the application on the target machine I get an error saying Office is not installed? I'm assuming then you have to have a registed Office to use the object libraries? Is there anyway around this as I do not have a Office license key lying around and its quite expensive?

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  • Dashcode Web App: How to programmatically manipulate bound array in dataSource?

    - by Kross
    Hi Everyone, I've started using Dashcode to write an interface for presenting the report data for some of our Cocoa tools. I am using a Dashcode data source and bindings to populate the elements in the WebView, and it all seems to be working well so far. One of the objects in my dataSource is an array of objects that I would like to manipulate programmatically. I can change the object values in the array just fine but if I want to replace the array, or any objects in the array, my bound table isn't able to observe the added objects. Here is the code that I thought would let me easily replace the bound array with new content: var dataSource = dashcode.getDataSource("reportData"); var newDetailArray = testArray(); dataSource.setValueForKeyPath(newDetailArray, "content.detailArray"); But this throws the exception: Exception while binding "content" to keypath "arrangedObjects " TypeError: Result of expression 'this.object.valueForKeyPath' [undefined] is not a function. Is there something I'm missing that will let me easily manipulate the array's contents programmatically?

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  • Clearing ColorConvertedBitmap in C#

    - by Jamie
    Hi guys, the problem is: I want to use the same ColorConvertedBitmap object for two purposes, firstly I set everyting: ColorConvertedBitmap conv = new ColorConvertedBitmap(); conv.BeginInit(); conv.SourceColorContext = new ColorContext(PixelFormats.Bgra32); conv.Source = myImage; conv.DestinationFormat = PixelFormats.Pbgra32; conv.DestinationColorContext = new ColorContext(PixelFormats.Pbgra32); conv.EndInit(); and then I would like to use the same object for another transformation. How to reset the values of ColorConvertedBitmap? Thank you for the reply! Cheers

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  • Rails: unexpected behavior updating a shared instance

    - by Pascal Lindelauf
    I have a User object, that is related to a Post object via two different association paths: Post --(has_many)-- comments --(belongs to)-- writer (of type User) Post --(belongs to)-- writer (of type User) Say the following hold: user1.name == "Bill" post1.comments[1].writer == user1 post1.writer == user1 Now when I retrieve the post1 and its comments from the database and I update post1.comments[1].writer like so: post1.comments[1].writer.name = "John" I would expect post1.writer to equal "John" too. But it doesn't! It still equals "Bill". So there seems to be some caching going on, but the kind I would not expect. I would expect Rails to be clever enough to load exactly one instance of the user with name "Bill"; instead is appears to load two individual ones: one for each association path. Can someone explain how this works exactly and how I am to handle these types of situations the "Rails way"?

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  • Trappings MySQL Warnings on Calls Wrapped in Classes -- Python

    - by chernevik
    I can't get Python's try/else blocks to catch MySQL warnings when the execution statements are wrapped in classes. I have a class that has as a MySQL connection object as an attribute, a MySQL cursor object as another, and a method that run queries through that cursor object. The cursor is itself wrapped in a class. These seem to run queries properly, but the MySQL warnings they generate are not caught as exceptions in a try/else block. Why don't the try/else blocks catch the warnings? How would I revise the classes or method calls to catch the warnings? Also, I've looked through the prominent sources and can't find a discussion that helps me understand this. I'd appreciate any reference that explains this. Please see code below. Apologies for verbosity, I'm newbie. #!/usr/bin/python import MySQLdb import sys import copy sys.path.append('../../config') import credentials as c # local module with dbase connection credentials #============================================================================= # CLASSES #------------------------------------------------------------------------ class dbMySQL_Connection: def __init__(self, db_server, db_user, db_passwd): self.conn = MySQLdb.connect(db_server, db_user, db_passwd) def getCursor(self, dict_flag=True): self.dbMySQL_Cursor = dbMySQL_Cursor(self.conn, dict_flag) return self.dbMySQL_Cursor def runQuery(self, qryStr, dict_flag=True): qry_res = runQueryNoCursor(qryStr=qryStr, \ conn=self, \ dict_flag=dict_flag) return qry_res #------------------------------------------------------------------------ class dbMySQL_Cursor: def __init__(self, conn, dict_flag=True): if dict_flag: dbMySQL_Cursor = conn.cursor(MySQLdb.cursors.DictCursor) else: dbMySQL_Cursor = conn.cursor() self.dbMySQL_Cursor = dbMySQL_Cursor def closeCursor(self): self.dbMySQL_Cursor.close() #============================================================================= # QUERY FUNCTIONS #------------------------------------------------------------------------------ def runQueryNoCursor(qryStr, conn, dict_flag=True): dbMySQL_Cursor = conn.getCursor(dict_flag) qry_res =runQueryFnc(qryStr, dbMySQL_Cursor.dbMySQL_Cursor) dbMySQL_Cursor.closeCursor() return qry_res #------------------------------------------------------------------------------ def runQueryFnc(qryStr, dbMySQL_Cursor): qry_res = {} qry_res['rows'] = dbMySQL_Cursor.execute(qryStr) qry_res['result'] = copy.deepcopy(dbMySQL_Cursor.fetchall()) qry_res['messages'] = copy.deepcopy(dbMySQL_Cursor.messages) qry_res['query_str'] = qryStr return qry_res #============================================================================= # USAGES qry = 'DROP DATABASE IF EXISTS database_of_armaments' dbConn = dbMySQL_Connection(**c.creds) def dbConnRunQuery(): # Does not trap an exception; warning displayed to standard error. try: dbConn.runQuery(qry) except: print "dbConn.runQuery() caught an exception." def dbConnCursorExecute(): # Does not trap an exception; warning displayed to standard error. dbConn.getCursor() # try/except block does catches error without this try: dbConn.dbMySQL_Cursor.dbMySQL_Cursor.execute(qry) except Exception, e: print "dbConn.dbMySQL_Cursor.execute() caught an exception." print repr(e) def funcRunQueryNoCursor(): # Does not trap an exception; no warning displayed try: res = runQueryNoCursor(qry, dbConn) print 'Try worked. %s' % res except Exception, e: print "funcRunQueryNoCursor() caught an exception." print repr(e) #============================================================================= if __name__ == '__main__': print '\n' print 'EXAMPLE -- dbConnRunQuery()' dbConnRunQuery() print '\n' print 'EXAMPLE -- dbConnCursorExecute()' dbConnCursorExecute() print '\n' print 'EXAMPLE -- funcRunQueryNoCursor()' funcRunQueryNoCursor() print '\n'

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  • MooTools: How to use responseText directly

    - by Johny
    In following example of code, I want to traverse the responseText object which consist the html code came from request_page.php file. In onSuccess event, i want to check whether < Div with id 'ersDiv' has any errors posted in it. new Request.HTML({ url: 'request_page.php', onSuccess: function(responseText, responseXML) { // My expected code to handle responseText object alert(errorMessage); }, onFailure: function() { } }); request_page.php file is like this : <div align='center'><div id='ersDiv'>Page loaded with insufficient data</div></div>

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  • Django or Drupal, which one should I use that suits best my needs ?

    - by HJ-INCPP
    Hello, I want to learn and use Drupal or Django for the following: dynamic web sites, medium database, multi-level users, paypal integration, content managment, speed (developing), security I like MVC, ORM and object-oriented prg. Which is better to jump into ? Which one is more mature, powerful, understandable, object-oriented and easier to use by the time ? What about Python Spring ... Also, which of these 3 are better documented, are better for a cv and have more extensions? Known languages: php, java, mysql Thank you !

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  • replace values in form.data when form fails validation

    - by John
    Hi I have a form field which requires a json object as its value when it is rendered. When the form is submitted it returns a comma seperated string of ids as its value (not a json string). however if the form does not validate i want to turn this string of ids back into a json string so it will display properly (is uses jquery to render the json object correctly). how would i do this? I was thinking of overwriting the form.clean method but when I tried to change self.data['fieldname'] I got the error 'This QueryDict instance is immutable' and when i tried to change self.cleaned_data['fieldname'] it didn't make a difference to the value of the field. Thanks

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  • jQuery.param() - doesn't serialize javascript Date objects?

    - by ehahn9
    jQuery.param({foo: 1}); // => "foo=1" - SUCCESS! jQuery.param({bar: new Date()}); // => "" - OUCH! There is no problem with encodeURIComponent(new Date()), which is what I would have thought param is calling for each member. Also, explicitly using "traditional" param (e.g. jQuery.param(xxx, true)) DOES serialize the date, but alas, that isn't of much help since my data structure isn't flat. Is this because typeof(Date) == "object" and param tries to descend into it to find scalar values? How might one realistically serialize an object that happens to have Date's in it for $.post() etc.?

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  • Problems Enforcing Referential Integrity on SQL Server Tables

    - by SidC
    Hello All, I have a SQL Server 2005 database comprised of Customer, Quote, QuoteDetail tables. I want/need to enforce referential integrity such that when an insert is made on quotedetail, the quote and customer tables are also affected. I have tried my best to set up primary/foreign keys on my tables but need some help. Here's the scripts for my tables as they stand now (please don't laugh): Customers: USE [Diel_inventory] GO /****** Object: Table [dbo].[Customers] Script Date: 05/08/2010 03:39:04 ******/ SET ANSI_NULLS ON GO SET QUOTED_IDENTIFIER ON GO CREATE TABLE [dbo].[Customers]( [pkCustID] [int] IDENTITY(1,1) NOT NULL, [CompanyName] [nvarchar](50) NULL, [Address] [nvarchar](50) NULL, [City] [nvarchar](50) NULL, [State] [nvarchar](2) NULL, [ZipCode] [nvarchar](5) NULL, [OfficePhone] [nvarchar](12) NULL, [OfficeFAX] [nvarchar](12) NULL, [Email] [nvarchar](50) NULL, [PrimaryContactName] [nvarchar](50) NULL, CONSTRAINT [PK_Customers] PRIMARY KEY CLUSTERED ([pkCustID] ASC)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] ) ON [PRIMARY] Quotes: USE [Diel_inventory] GO /****** Object: Table [dbo].[Quotes] Script Date: 05/08/2010 03:30:46 ******/ SET ANSI_NULLS ON GO SET QUOTED_IDENTIFIER ON GO CREATE TABLE [dbo].[Quotes]( [pkQuoteID] [int] IDENTITY(1,1) NOT NULL, [fkCustomerID] [int] NOT NULL, [QuoteDate] [timestamp] NOT NULL, [NeedbyDate] [datetime] NULL, [QuoteAmt] [decimal](6, 2) NOT NULL, [QuoteApproved] [bit] NOT NULL, [fkOrderID] [int] NOT NULL, CONSTRAINT [PK_Bids] PRIMARY KEY CLUSTERED ( [pkQuoteID] ASC)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] ) ON [PRIMARY] GO ALTER TABLE [dbo].[Quotes] WITH CHECK ADD CONSTRAINT [fkCustomerID] FOREIGN KEY([fkCustomerID]) REFERENCES [dbo].[Customers] ([pkCustID]) GO ALTER TABLE [dbo].[Quotes] CHECK CONSTRAINT [fkCustomerID] QuoteDetail: USE [Diel_inventory] GO /****** Object: Table [dbo].[QuoteDetail] Script Date: 05/08/2010 03:31:58 ******/ SET ANSI_NULLS ON GO SET QUOTED_IDENTIFIER ON GO CREATE TABLE [dbo].[QuoteDetail]( [ID] [int] IDENTITY(1,1) NOT NULL, [fkQuoteID] [int] NOT NULL, [fkCustomerID] [int] NOT NULL, [fkPartID] [int] NULL, [PartNumber1] [float] NOT NULL, [Qty1] [int] NOT NULL, [PartNumber2] [float] NULL, [Qty2] [int] NULL, [PartNumber3] [float] NULL, [Qty3] [int] NULL, [PartNumber4] [float] NULL, [Qty4] [int] NULL, [PartNumber5] [float] NULL, [Qty5] [int] NULL, [PartNumber6] [float] NULL, [Qty6] [int] NULL, [PartNumber7] [float] NULL, [Qty7] [int] NULL, [PartNumber8] [float] NULL, [Qty8] [int] NULL, [PartNumber9] [float] NULL, [Qty9] [int] NULL, [PartNumber10] [float] NULL, [Qty10] [int] NULL, [PartNumber11] [float] NULL, [Qty11] [int] NULL, [PartNumber12] [float] NULL, [Qty12] [int] NULL, [PartNumber13] [float] NULL, [Qty13] [int] NULL, [PartNumber14] [float] NULL, [Qty14] [int] NULL, [PartNumber15] [float] NULL, [Qty15] [int] NULL, [PartNumber16] [float] NULL, [Qty16] [int] NULL, [PartNumber17] [float] NULL, [Qty17] [int] NULL, [PartNumber18] [float] NULL, [Qty18] [int] NULL, [PartNumber19] [float] NULL, [Qty19] [int] NULL, [PartNumber20] [float] NULL, [Qty20] [int] NULL, CONSTRAINT [PK_QuoteDetail] PRIMARY KEY CLUSTERED ( [ID] ASC )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] ) ON [PRIMARY] GO ALTER TABLE [dbo].[QuoteDetail] WITH CHECK ADD CONSTRAINT [FK_QuoteDetail_Customers] FOREIGN KEY ([fkCustomerID]) REFERENCES [dbo].[Customers] ([pkCustID]) GO ALTER TABLE [dbo].[QuoteDetail] CHECK CONSTRAINT [FK_QuoteDetail_Customers] GO ALTER TABLE [dbo].[QuoteDetail] WITH CHECK ADD CONSTRAINT [FK_QuoteDetail_PartList] FOREIGN KEY ([fkPartID]) REFERENCES [dbo].[PartList] ([RecID]) GO ALTER TABLE [dbo].[QuoteDetail] CHECK CONSTRAINT [FK_QuoteDetail_PartList] GO ALTER TABLE [dbo].[QuoteDetail] WITH CHECK ADD CONSTRAINT [FK_QuoteDetail_Quotes] FOREIGN KEY([fkQuoteID]) REFERENCES [dbo].[Quotes] ([pkQuoteID]) GO ALTER TABLE [dbo].[QuoteDetail] CHECK CONSTRAINT [FK_QuoteDetail_Quotes] Your advice/guidance on how to set these up so that customer ID in Customers is the same as in Quotes (referential integrity) and that CustomerID is inserted on Quotes and Customers when an insert is made to QuoteDetial would be much appreciated. Thanks, Sid

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  • How can I type cast EventArgs to have a .point property in c#? [closed]

    - by Sean Smyth
    I'm working with a double click function in c#. the function takes an object and EventArgs as it's parameters: private void gvHL7_DoubleClick(object sender, EventArgs e){ . . . } However, I want to use the .Point property, and EventArgs doesn't have that property. I know that DevExpress.XtraGrid.Views.Grid.GridMenuEventArgs does, but it's saying that's an invalid casting. What type should I cast my EventArgs instance to if I wish to access the .Point property? Edit: The double click function I'm working with is provided by devexpress for their grids.

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  • Trying and expand the contrib.auth.user model and add a "relatipnships" manage

    - by dotty
    I have the following model setup. from django.db import models from django.contrib.auth.models import User class SomeManager(models.Manager): def friends(self): # return friends bla bla bla class Relationship(models.Model): """(Relationship description)""" from_user = models.ForeignKey(User, related_name='from_user') to_user = models.ForeignKey(User, related_name='to_user') has_requested_friendship = models.BooleanField(default=True) is_friend = models.BooleanField(default=False) objects = SomeManager() relationships = models.ManyToManyField(User, through=Relationship, symmetrical=False) relationships.contribute_to_class(User, 'relationships') Here i take the User object and use contribute_to_class to add 'relationships' to the User object. The relationship show up, but if call User.relationships.friends it should run the friends() method, but its failing. Any ideas how i would do this? Thanks

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  • How do I call the methods in a model via controller? Zend Framework

    - by Joel
    Hi guys, I've been searching for tutorials to better understand this, but I'm having no luck. Please forgive the lengthy explination, but I want make sure I explain myself well. First, I'm quite new to the MVC structure, though I have been doing tutorials and learning as best I can. I have been moving over a live site into the Zend Framework model. So far, I have all the views within views/scripts/index/example.phtml. So therefore I'm using one IndexController and I have the code in each Action method for each page: IE public function exampleAction() Because I didn't know how to interact with a model, I put all the methods at the bottom of the controller (a fat controller). So basically, I had a working site by using a View and Controller and no model. ... Now I'm trying to learn how to incorporate the Model. So I created a View at: view/scripts/calendar/index.phtml I created a new Controller at: controller/CalendarControllers.php and a new model at: model/Calendar.php The problem is I think I'm not correctly communication with the model (I'm still new to OOP). Can you look over my controller and model and tell me if you see a problem. I'm needing to return an array from runCalendarScript(), but I'm not sure if I can return an array into the object like I'm trying to? I don't really understand how to "run" the runCalendarScript() from the controller? Thanks for any help! I'm stripping out most of the guts of the methods for the sake of brevity: controller: <?php class CalendarController extends Zend_Controller_Action { public function indexAction() { $finishedFeedArray = new Application_Model_Calendar(); $this->view->googleArray = $finishedFeedArray; } } model: <?php class Application_Model_Calendar { public function _runCalendarScript(){ $gcal = $this->_validateCalendarConnection(); $uncleanedFeedArray = $this->_getCalendarFeed($gcal); $finishedFeedArray = $this->_cleanFeed($uncleanedFeedArray); return $finishedFeedArray; } //Validate Google Calendar connection public function _validateCalendarConnection() { ... return $gcal; } //extracts googles calendar object into the $feed object public function _getCalendarFeed($gcal) { ... return $feed; } //cleans the feed to just text, etc protected function _cleanFeed($uncleanedFeedArray) { $contentText = $this->_cleanupText($event); $eventData = $this->_filterEventDetails($contentText); return $cleanedArray; } //Cleans up all formatting of text from Calendar feed public function _cleanupText($event) { ... return $contentText; } //filterEventDetails protected function _filterEventDetails($contentText) { ... return $data; } }

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  • Element point map for html5 canvas element, need algorithm

    - by Artiom Chilaru
    I'm currently working on a pure html 5 canvas implementation of the "flying tag cloud sphere", which many of you have undoubtedly seen as a flash object in some pages. The tags are drawn fine, and the performance is satisfactory, but there's one thing in the canvas element that's kind of breaking this idea: you can't identify the objects that you've drawn on a canvas, as it's just a simple flat "image".. What I have to do in this case is catch the click event, and try to "guess" which element was clicked. So I have to have some kind of matrix, which stores a link to a tag object for each pixel on the canvas, AND I have to update this matrix on every redraw. Now this sounds incredibly inefficient, and before I even start trying to implement this, I want to ask the community - is there some "well known" algorithm that would help me in this case? Or maybe I'm just missing something, and the answer is right behind the corner? :)

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  • PHP MySQLi and MySQLi_STMT: Which insert_id to use?

    - by Carvell Fenton
    Hello all, Both the MySQLi and MySQLi_STMT classes have an $insert_id property. If I am connected to my database using a MySQLi object (say $db), and then I perform an INSERT with a MySQLi_STMT object (say $stmt), to get the id of the last INSERT, should I use: $last_id = $db->insert_id; or $last_id = $stmt->insert_id; Or would they be the same, in which case it doesn't matter? I thought this might be a quick answer for someone, and save me the time of writing the test code to check it. Thanks in advance as always.

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  • How to read from CSS files with jQuery

    - by Neurofluxation
    Ok, I have a HTML page with jQuery included. I have a CSS file with a good load of lines in, I would like to read all styles for a given element from the external CSS file... Not the inline styles... I have the following code (which looks like it should work...): var styleProperties= {}; var getCssProperties = ['width', 'margin', 'height']; for (c=0;i<=returnStyleProps.length;c++) { styleProperties[returnStyleProps[c]] = $('div#container').css(returnStyleProps[c]); alert(styleProperties); } alert(styleProperties); But this only seems to alert: "[Object Object]" Any ideas you clever people?

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  • What wording in the C++ standard allows static_cast<non-void-type*>(malloc(N)); to work?

    - by ben
    As far as I understand the wording in 5.2.9 Static cast, the only time the result of a void*-to-object-pointer conversion is allowed is when the void* was a result of the inverse conversion in the first place. Throughout the standard there is a bunch of references to the representation of a pointer, and the representation of a void pointer being the same as that of a char pointer, and so on, but it never seems to explicitly say that casting an arbitrary void pointer yields a pointer to the same location in memory, with a different type, much like type-punning is undefined where not punning back to an object's actual type. So while malloc clearly returns the address of suitable memory and so on, there does not seem to be any way to actually make use of it, portably, as far as I have seen.

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  • Problem at JUnit test with generics

    - by Tom Brito
    In my utility method: public static <T> T getField(Object obj, Class c, String fieldName) { try { Field field = c.getDeclaredField(fieldName); field.setAccessible(true); return (T) field.get(obj); } catch (Exception e) { e.printStackTrace(); fail(); return null; } } The line return (T) field.get(obj); gives the warning "Type safety: Unchecked cast from Object to T"; but I cannot perform instanceof check against type parameter T, so what am I suppose to do here?

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  • Why are static classes considered “classes” and “reference types”?

    - by Timwi
    I’ve been pondering about the C# and CIL type system today and I’ve started to wonder why static classes are considered classes. There are many ways in which they are not really classes: A “normal” class can contain non-static members, a static class can’t. In this respect, a class is more similar to a struct than it is to a static class, and yet structs have a separate name. You can have a reference to an instance of a “normal” class, but not a static class (despite it being considered a “reference type”). In this respect, a class is more similar to an interface than it is to a static class, and yet interfaces have a separate name. The name of a static class can never be used in any place where a type name would normally fit: you can’t declare a variable of this type, you can’t use it as a base type, and you can’t use it as a generic type parameter. In this respect, static classes are somewhat more like namespaces. A “normal” class can implement interfaces. Once again, that makes classes more similar to structs than to static classes. A “normal” class can inherit from another class. It is also bizarre that static classes are considered to derive from System.Object. Although this allows them to “inherit” the static methods Equals and ReferenceEquals, the purpose of that inheritance is questionable as you would call those methods on object anyway. C# even allows you to specify that useless inheritance explicitly on static classes, but not on interfaces or structs, where the implicit derivation from object and System.ValueType, respectively, actually has a purpose. Regarding the subset-of-features argument: Static classes have a subset of the features of classes, but they also have a subset of the features of structs. All of the things that make a class distinct from the other kinds of type, do not seem to apply to static classes. Regarding the typeof argument: Making a static class into a new and different kind of type does not preclude it from being used in typeof. Given the sheer oddity of static classes, and the scarcity of similarities between them and “normal” classes, shouldn’t they have been made into a separate kind of type instead of a special kind of class?

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  • Should GSON ignore varying types if they're not used in a class?

    - by loeschg
    I'm making an API call that returns JSON which has a particular field which either returns false or a map depending on content. It's a field that I don't care about. I expected GSON to ignore this particular field, though it doesn't seem to be. The object generation fails with the following message: com.google.gson.JsonSyntaxException: java.lang.IllegalStateException: Expected a string but was BEGIN_OBJECT at line 1 column 403560 I've seen this particular question (Gson deserialize json with varying value types). I want to make sure I need to make a custom deserializer before doing so. I'm wondering if I may have another issue. edit: Example: "anonymous_flag": { } vs "anonymous_flag": "yes" Another Edit: I actually had the field in my model object... I was referencing the wrong class. Judge away :)

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  • Manipulating individual rows of a datagrid

    - by pfranchise
    Hey, recently I started working on a webpage that has a datagrid. I understand how to add datasources and that sort of thing, or at least I am starting to get it. But my question is about manipulating individual rows or cells. Is that only possible during the databind event handler, that is the only place I have been able to do it so far. I am sure there is a more abstract way of doing the things I want to do, but there are times where I just want to say Datagrid.add(row). I mean, if the datagrid is made up of a certain object type, can I make a new object of that type and just chuck it on the end? I am still new to this stuff, so perhaps what I want to do would defeat the purpose of this added abstraction, but figured I would ask around. Thanks for any advice, tips, or tricks people feel like sharing. Edit: for clarification I am using c#, entity framework, asp.net, and an SQL database.

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  • NHibernate - get List<long> representing primary keys?

    - by Nathan
    I have a situation where I definitely don't want to get the whole domain object. Basically, the entity has a primary key of long (.NET)/bigint(sql server 2005). I simply need to pass the primary key to an external system which will access the database directly - and since the list of ids could be large, I don't want to rehydrate the entire domain object just to get the Id. In linq2sql, I could accomplish this with a projection, but I am restricted to NHibernate 1.2.1.4000, which doesn't support Linq. Is there a way to accomplish this using NHibernate 1.2.1.4000? (I am open to using a named-query if that will work)

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  • Resetting Objects vs. Constructing New Objects

    - by byronh
    Is it considered better practice and/or more efficient to create a 'reset' function for a particular object that clears/defaults all the necessary member variables to allow for further operations, or to simply construct a new object from outside? I've seen both methods employed a lot, but I can't decide which one is better. Of course, for classes that represent database connections, you'd have to use a reset method rather than constructing a new one resulting in needless connecting/disconnecting, but I'm talking more in terms of abstraction classes. Can anyone give me some real-world examples of when to use each method? In my particular case I'm thinking mostly in terms of ORM or the Model in MVC. For example, if I would want to retrieve a bunch of database objects for display and modify them in one operation.

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