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Why do bind1st and bind2nd require constant function objects?

- by rlbond

So, I was writing a C++ program which would allow me to take control of the entire world. I was all done writing the final translation unit, but I got an error: error C3848: expression having type 'const `anonymous-namespace'::ElementAccumulator<T,BinaryFunction>' would lose some const-volatile qualifiers in order to call 'void `anonymous-namespace'::ElementAccumulator<T,BinaryFunction>::operator ()(const point::Point &,const int &)' with [ T=SideCounter, BinaryFunction=std::plus<int> ] c:\program files (x86)\microsoft visual studio 9.0\vc\include\functional(324) : while compiling class template member function 'void std::binder2nd<_Fn2>::operator ()(point::Point &) const' with [ _Fn2=`anonymous-namespace'::ElementAccumulator<SideCounter,std::plus<int>> ] c:\users\****\documents\visual studio 2008\projects\TAKE_OVER_THE_WORLD\grid_divider.cpp(361) : see reference to class template instantiation 'std::binder2nd<_Fn2>' being compiled with [ _Fn2=`anonymous-namespace'::ElementAccumulator<SideCounter,std::plus<int>> ] I looked in the specifications of binder2nd and there it was: it took a const AdaptibleBinaryFunction. So, not a big deal, I thought. I just used boost::bind instead, right? Wrong! Now my take-over-the-world program takes too long to compile (bind is used inside a template which is instantiated quite a lot)! At this rate, my nemesis is going to take over the world first! I can't let that happen -- he uses Java! So can someone tell me why this design decision was made? It seems like an odd decision. I guess I'll have to make some of the elements of my class mutable for now...

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Silverlight 3 data-binding child property doesn't update

- by sonofpirate

I have a Silverlight control that has my root ViewModel object as it's data source. The ViewModel exposes a list of Cards as well as a SelectedCard property which is bound to a drop-down list at the top of the view. I then have a form of sorts at the bottom that displays the properties of the SelectedCard. My XAML appears as (reduced for simplicity): <StackPanel Orientation="Vertical"> <ComboBox DisplayMemberPath="Name" ItemsSource="{Binding Path=Cards}" SelectedItem="{Binding Path=SelectedCard, Mode=TwoWay}" /> <TextBlock Text="{Binding Path=SelectedCard.Name}" /> <ListBox DisplayMemberPath="Name" ItemsSource="{Binding Path=SelectedCard.PendingTransactions}" /> </StackPanel> I would expect the TextBlock and ListBox to update whenever I select a new item in the ComboBox, but this is not the case. I'm sure it has to do with the fact that the TextBlock and ListBox are actually bound to properties of the SelectedCard so it is listening for property change notifications for the properties on that object. But, I would have thought that data-binding would be smart enough to recognize that the parent object in the binding expression had changed and update the entire binding. It bears noting that the PendingTransactions property (bound to the ListBox) is lazy-loaded. So, the first time I select an item in the ComboBox, I do make the async call and load the list and the UI updates to display the information corresponding to the selected item. However, when I reselect an item, the UI doesn't change! For example, if my original list contains three cards, I select the first card by default. Data-binding does attempt to access the PendingTransactions property on that Card object and updates the ListBox correctly. If I select the second card in the list, the same thing happens and I get the list of PendingTransactions for that card displayed. But, if I select the first card again, nothing changes in my UI! Setting a breakpoint, I am able to confirm that the SelectedCard property is being updated correctly. How can I make this work???

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Float addition promoted to double?

- by Andreas Brinck

I had a small WTF moment this morning. Ths WTF can be summarized with this: float x = 0.2f; float y = 0.1f; float z = x + y; assert(z == x + y); //This assert is triggered! (Atleast with visual studio 2008) The reason seems to be that the expression x + y is promoted to double and compared with the truncated version in z. (If i change z to double the assert isn't triggered). I can see that for precision reasons it would make sense to perform all floating point arithmetics in double precision before converting the result to single precision. I found the following paragraph in the standard (which I guess I sort of already knew, but not in this context): 4.6.1. "An rvalue of type float can be converted to an rvalue of type double. The value is unchanged" My question is, is x + y guaranteed to be promoted to double or is at the compiler's discretion? UPDATE: Since many people has claimed that one shouldn't use == for floating point, I just wanted to state that in the specific case I'm working with, an exact comparison is justified. Floating point comparision is tricky, here's an interesting link on the subject which I think hasn't been mentioned.

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ViewModel Views relation/link/syncroniztion

- by mehran

Third try to describing problem: Try 1: Sunchronizing view model and view Try2: WPF ViewModel not active presenter Try3: I have some class for view models: public class Node : INotifyPropertyChanged { Guid NodeId { get; set; } public string Name { get; set; } } public class Connection: INotifyPropertyChanged { public Node StartNode { get; set; } public Node EndNode { get; set; } } public class SettingsPackModel { public List<Node> Nodes { get; private set; } public List<Connection> Connections { get; private set; } } I also have some templates to displays these models: <DataTemplate DataType="{x:Type vm:Node}">…</DataTemplate> <DataTemplate DataType="{x:Type vm:Connection}"> <my:ConnectionElment StartNodeElment="???" EndNodeElment="???"> </my:ConnectionElment> <DataTemplate> But the problem is that DataTemplate for Connection need reference ot two element of type UIElement , how can I pass these two, how can I fill ??? in above expression?

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Weird splitter behaviour when moving it

- by tomo

My demo app displays two rectangles which should fill whole browser's screen. There is a vertical splitter between them. This looks like a basic scenario but I have no idea how to implement this in xaml. I cannot force this to fill whole screen and when moving splitter then whole screen grows. Can anybody help? <UserControl xmlns:controls="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls" x:Class="SilverlightApplication1.MainPage" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" mc:Ignorable="d" d:DesignWidth="640" d:DesignHeight="480"> <Grid x:Name="LayoutRoot" VerticalAlignment="Stretch" HorizontalAlignment="Stretch"> <Grid.ColumnDefinitions> <ColumnDefinition Width="Auto"/> <ColumnDefinition Width="Auto"/> <ColumnDefinition Width="Auto"/> </Grid.ColumnDefinitions> <Border BorderBrush="Black" BorderThickness="1" VerticalAlignment="Stretch" HorizontalAlignment="Stretch" MinWidth="50"> </Border> <controls:GridSplitter Grid.Column="1" VerticalAlignment="Stretch" Width="Auto" ></controls:GridSplitter> <Border BorderBrush="Blue" BorderThickness="1" VerticalAlignment="Stretch" HorizontalAlignment="Stretch" Grid.Column="2" MinWidth="50"></Border> </Grid> </UserControl>

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Unable to get values in ftl from value stack in custom Result Type

- by Nagadev

Hello, I am unable retrieve value from value stack in FTL file. Here is the code. Action class holds a property called 'name' private String name; public String getName() { return name; } public void setName(String name) { this.name = name; } public String execute(){ setName("From value stack .. "); return SUCCESS; } FTL code: ${name} Custom result Type deExecute Method Configuration configuration = new Configuration(); String templatePath = "/ftl"; ServletContext context = ServletActionContext.getServletContext(); configuration.setServletContextForTemplateLoading(context, templatePath); configuration.setObjectWrapper(new DefaultObjectWrapper()); Template template = configuration.getTemplate("sample.ftl"); OutputStreamWriter out = new OutputStreamWriter(System.out); template.process(ActionContext.getContext().getValueStack(), out); I am passing the value Stack which contains recently executed Action as well. But FTL is throwing an exception Expression name is undefined on line 1, column 3 in sample.ftl I tried with passing session instead of value stack and I could get the value in FTL. Please suggest me a way to get values from Action class to FTL from value stack. Thanks inadvance.

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C standard addressing simplification inconsistency

- by Chris Lutz

Section §6.5.3.2 "Address and indirection operators" ¶3 says (relevant section only): The unary & operator returns the address of its operand. ... If the operand is the result of a unary * operator, neither that operator nor the & operator is evaluated and the result is as if both were omitted, except that the constraints on the operators still apply and the result is not an lvalue. Similarly, if the operand is the result of a [] operator, neither the & operator nor the unary * that is implied by the [] is evaluated and the result is as if the & operator were removed and the [] operator were changed to a + operator. ... This means that this: int *i = NULL; printf("%p", (void *) (&*i) ); printf("%p", (void *) (&i[10]) ); Should be perfectly legal, printing the null pointer (probably 0) and the null pointer plus 10 (probably 10). The standard seems very clear that both of those cases are required to be optimized. However, it doesn't seem to require the following to be optimized: struct { int a; short b; } *s = 0; printf("%p", (void *) (&s->b) ); This seems awfully inconsistent. I can see no reason that the above code shouldn't print the null pointer plus sizeof(int) (possibly 4). Simplifying a &-> expression is going to be the same conceptually (IMHO) as &[], a simple address-plus-offset. It's even an offset that's going to be determinable at compile time, rather than potentially runtime with the [] operator. Is there anything in the rationale about why this is so seemingly inconsistent?

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JFLAP Turing Machine shortcut problem

- by Robert Lamb

In JFLAP (http://jflap.org), there are some shortcuts for Turing machine transitions. One of these shortcuts allows you to transition as long as the current tape symbol isn't the indicated symbol. For example, the transition !g,x;R basically says "Take this transition if the current tape symbol is not g". So far, so good. But the transition I want is !?,~;R which basically says "Move right as long as the current symbol is not the end-of-string (empty cell) symbol". The problem is I cannot figure out how to type in "!?". The JFLAP online documentation (http://www.jflap.org/tutorial/turing/one/index.html#syntax) has this to say: The first shortcut is that there exists the option of using the “!” character to convey the meaning of “any character but this character.” For example, concerning the transition (!a; x, R), if the head encounters any character but an “a”, it will replace the character with an “x” and move right. To write the expression “!?”, just type a “1” in when inputting a command. My question is...how do I actually do what that last sentence is trying to explain to me? Thanks for your help! Robert

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Checking for valid email addresses

- by Roland

I'm running a website with more than 60 000 registered users. Every week notifications are send to these users via email, now I've noticed some of the mail addresses do not exists anymore eg. the domain address is valid but the email name en asdas@ is not valid anymore since person does not work at a company anymore etc. Now I'm looping through the database and doing some regular expression checks and checking if the MX records exist with the following two functions function verify_email($email){ if(!preg_match('/^[_A-z0-9-]+((\.|\+)[_A-z0-9-]+)*@[A-z0-9-]+(\.[A-z0-9-]+)*(\.[A-z]{2,4})$/',$email)){ return false; } else { return true; } } // Our function to verify the MX records function verify_email_dns($email){ list($name, $domain) = split('@',$email); if(!checkdnsrr($domain,'MX')){ return false; } else { return true; } } If the email address is in an invalid format or the domain does not exists I delete the users account. Are there any methods I could use to check if the email address still exists or not if the domain name is valid and the email address is in the correct format? For example [email protected] does not exist anymore but test.com is a valid domain name.

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Set "Start With" value for Oracle sequence dynamically

- by Allan

I'm trying to create a release script that can be deployed on multiple databases, but where the data can be merged back together at a later date. The obvious way to handle this is to set the sequence numbers for production data sufficiently high in subsequent deployments to prevent collisions. The problem is in coming up with a release script that will accept the environment number and set the "Start With" value of the sequences appropriately. Ideally, I'd like to use something like this: ACCEPT EnvironNum PROMPT 'Enter the Environment Number: ' --[more scripting] CREATE SEQUENCE seq1 START WITH &EnvironNum*100000; --[more scripting] This doesn't work because you can't evaluate a numeric expression in DDL. Another option is to create the sequences using dynamic SQL via PL/SQL. ACCEPT EnvironNum PROMPT 'Enter the Environment Number: ' --[more scripting] EXEC execute immediate 'CREATE SEQUENCE seq1 START WITH ' || &EnvironNum*100000; --[more scripting] However, I'd prefer to avoid this solution as I generally try to avoid issuing DDL in PL/SQL. Finally, the third option I've come up with is simply to accept the Start With value as a substitution variable, instead of the environment number. Does anyone have a better thought on how to go about this?

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How much detail should be in a project plan or spec?

- by DeanMc

I have an issue that I feel many programmers can relate to... I have worked on many small scale projects. After my initial paper brain storm I tend to start coding. What I come up with is usually a rough working model of the actual application. I design in a disconnected fashion so I am talking about underlying code libraries, user interfaces are the last thing as the library usually dictates what is needed in the UI. As my projects get bigger I worry that so should my "spec" or design document. The above paragraph, from my investigations, is echoed all across the internet in one fashion or another. When a UI is concerned there is a bit more information but it is UI specific and does not relate to code libraries. What I am beginning to realise is that maybe code is code is code. It seems from my extensive research that there is no 1:1 mapping between a design document and the code. When I need to research a topic I dump information into OneNote and from there I prioritise features into versions and then into related chunks so that development runs in a fairly linear fashion, my tasks tend to look like so: Implement Binary File Reader Implement Binary File Writer Create Object to encapsulate Data for expression to the caller Now any programmer worth his salt is aware that between those three to do items could be a potential wall of code that could expand out to multiple files. I have tried to map the complete code process for each task but I simply don't think it can be done effectively. By the time one mangles pseudo code it is essentially code anyway so the time investment is negated. So my question is this: Am I right in assuming that the best documentation is the code itself. We are all in agreement that a high level overview is needed. How high should this be? Do you design to statement, class or concept level? What works for you?

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Tools\addin's for formating or cleaning up xaml?

- by cody

I'm guessing these don't exist since I searched around for these but I'm looking for a few tools: 1) A tool that cleans up my xaml so that the properties of elements are consistent through a file. I think enforcing that consistence would make the xaml easier to read. Maybe there could be a hierarchy of what comes first but if not alphabetical might work. Example before: TextBox Name="myTextBox1" Grid.Row="3" Grid.Column="1" Margin="4" TextBox Grid.Column="1" Margin="4" Name="t2" Grid.Row="3" Example after: TextBox Name="myTextBox1" Grid.Row="3" Grid.Column="1" Margin="4" TextBox Name="t2" Grid.Row="3" Grid.Column="1" Margin="4" (note < / has been remove from the above since control seem to have issues parsing whe the after section was added) 2) Along the same lines as above, to increase readability, a tool to align properties, so from the above code example similar props would start in the same place. <TextBox Name="myTextBox1" Grid.Row="3" Grid.Column="1" Margin="4"/> <TextBox Name="t2" Grid.Row="3" Grid.Column="1" Margin="4"/> I know VS has default settings for XAML documents so props can be on one line or separate lines so maybe if there was a tool as described in (1) this would not be needed...but it would still be nice if you like your props all on one line. 3) A tool that adds X to the any of the Grid.Row values and Y to any of the Grid.Column values in the selected text. Every time I add a new row\column I have to go manually fix these. From my understanding Expression Blend can help with this but seem excessive to open Blend just to increment some numbers (and just don't grok Blend). Maybe vs2010 with the designer will help but right now I'm on VS08 and Silverlight. Any one know of any tools to help with this? Anyone planning to write something like this...I'm looking at you JetBrains and\or DevExpress. Thanks.

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Using ADO.NET Entities LINQ Provider to model complex SQL Queries?

- by Ivan Zlatanov

What I find really powerful in ADO.NET Entities or LINQ to SQL, is the ability to model complex queries. I really don't need the mappings that Entities or LINQ to SQL are doing for me - I just need the ability to model complex expressions that can be translated into T-SQL. My question is - am I abusing too much? Can I use the Entity Framework for modeling queries and just that? Should I? I know I can write my own custom LINQ to SQL provider, but that is just not possible to handle in the time spans I have. What is the best approach to model complex T-SQL queries? How do you handle conditional group byes, orders, joins, unions etc in the OOP world? Using StringBuilders for this kind of job feels too ugly and harder to maintain given the possibilities we have with Expression Trees. When I use StringBuilder to model a complex SQL Query I feel kind of guilty! I feel the same way as when I have to hard code any number into my code that is different than 0 or 1. Feeling that makes you ask yourself if there is a better and cleaner way of doing it... I must mention that I am using C# 4.0, but I am not specifically looking for an answer in this language, but rather in the domain of CLR 4.

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Is it possible to split HTML using DOMDocument?

- by Lynn Adrianna

Using DOMDocument, is it possible to split a block of HTML by text wrapped in tags and those that are not, while maintaining the order? Sorry, if this doesn't make sense. My example should make it clear. Let's say I have the following block of HTML: text1<b style="color:pink">text2</b>text3<b>text4</b> <b style="font-weight:bold">text5</b> Is it possible create an array as such: array( [0] => text1 [1] => <b style="color:pink">text2</b> [2] => text3 [3] => <b>text4</b> [4] => [5] => <b style="font-weight:bold">text5</b> ) Below is my current working solution, which uses a regular expression, to split the HTML. $tokens = preg_split('/(<b\b[^>]*>.*?<\/b>)/i', $html, null, PREG_SPLIT_DELIM_CAPTURE); However, I always read that it is a bad idea to parse HTML using regular expressions, so was just wondering if there is a better way.

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How do I tell nant to only call csc when there are cs files in to compile?

- by rob_g

In my NAnt script I have a compile target that calls csc. Currently it fails because no inputs are specified: <target name="compile"> <csc target="library" output="${umbraco.bin.dir}\Mammoth.${project::get-name()}.dll"> <sources> <include name="project/*.cs" /> </sources> <references> </references> </csc> </target> How do I tell NAnt to not execute the csc task if there are no CS files? I read about the 'if' attribute but am unsure what expression to use with it, as ${file::exists('*.cs')} does not work. The build script is a template for Umbraco (a CMS) projects and may or may not ever have .cs source files in the project. Ideally I would like to not have developers need to remember to modify the NAnt script to include the compile task when .cs files are added to the project (or exclude it when all .cs files are removed).

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problems selecting a mutliple select value from database in Rails

- by Ramy

From inside of a form_for in rails, I'm inserting multiple select values into the database, like this: <div class="new-partner-form"> <%= form_for [:admin, matching_profile.partner, matching_profile], :html => {:id => "edit_profile", :multipart => true} do |f| %> <%= f.submit "Submit", :class => "hidden" %> <div class="rounded-block quarter-wide radio-group"> <h4>Exclude customers from source:</h4> <%= f.select :source, User.select(:source).group(:source).order(:source).map {|u| [u.source,u.source]}, {:include_blank => false}, {:multiple => true} %> <%= f.error_message_on :source %> </div> I'm then trying to pull the value from the database like this: def does_not_contain_source(matching_profiles) Expression.select(matching_profiles, :source) do |keyword| Rails.logger.info("Keyword is : " + keyword) @customer_source_tokenizer ||= Tokenizer.new(User.select(:source).where("id = ?", self.owner_id).map {|u| u.source}[0]) #User.select("source").where("id = ?", self.owner_id).to_s) @customer_source_tokenizer.divergent?(keyword) end end but getting this: ExpressionErrors: Bad syntax: --- - "" - B - "" this is what the value is in the database but it seems to choke when i access it this way. What's the right way to do this?

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Why are references compacted inside Perl lists?

- by parkan

Putting a precompiled regex inside two different hashes referenced in a list: my @list = (); my $regex = qr/ABC/; push @list, { 'one' => $regex }; push @list, { 'two' => $regex }; use Data::Dumper; print Dumper(\@list); I'd expect: $VAR1 = [ { 'one' => qr/(?-xism:ABC)/ }, { 'two' => qr/(?-xism:ABC)/ } ]; But instead we get a circular reference: $VAR1 = [ { 'one' => qr/(?-xism:ABC)/ }, { 'two' => $VAR1->[0]{'one'} } ]; This will happen with indefinitely nested hash references and shallowly copied $regex. I'm assuming the basic reason is that precompiled regexes are actually references, and references inside the same list structure are compacted as an optimization (\$scalar behaves the same way). I don't entirely see the utility of doing this (presumably a reference to a reference has the same memory footprint), but maybe there's a reason based on the internal representation Is this the correct behavior? Can I stop it from happening? Aside from probably making GC more difficult, these circular structures create pretty serious headaches. For example, iterating over a list of queries that may sometimes contain the same regular expression will crash the MongoDB driver with a nasty segfault (see https://rt.cpan.org/Public/Bug/Display.html?id=58500)

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SQL Server 2005 Import from Excel

- by user327045

I'd like to know what my best option would be to import data from an excel file on a weekly or monthly basis. At first, I thought I would use SSIS, but after much struggle with seemingly simple tasks, I'm starting to rethink my plan. Would it be better/easier to just write the SQL by hand or use the services of an SSIS package? The basic process will be as follows: A separate process will download an .xls file to a local fileshare. The xls file will have a filename like: 'myfilename MON YY'. I will need to read the month and year from the the filename, reformat it to a sql date and then query a DimDate table to find the corresponding date key. For each row (after the first 2 header rows), insert the data with the date key, unless the row is a total row, then ignore. Here are some of the issues I've been encountering with SSIS: I can parse the date string from a flat file datasource, but can't seem to do it with an excel data source. Also, once parsed, i cannot seem to convert the string to a date in order to perform the lookup for the date key. For example, I want to do something like this: select DateKey from DimDate where ActualDate = convert(datetime, '01-' + 'JAN-10', 120) but i don't think it is possible to use the 'convert' or 'datetime' keywords in an expression builder. I have been also unable to find where I can edit the SQL to ignore the first 2 rows of data. I'm very skeptical of using SSIS because it seems like a Kludgy way of doing something that can probably be accomplished more efficiently writing the SQL yourself, but I may be forced to use SSIS. Thoughts?

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Binding a Value from a View-Model to the View-Model of a child User Control in Silverlight?

- by andrej351

Hi there, So i have a UserControl for one of my Views and have another 'child' UserControl inside that. The outer 'parent' UserControl has a Collection on its View-Model and a Grid control on it to display a list of Items. I want to place another UserControl inside this UserControl to display a form representing the details of one Item. The outer / parent UserControl's View-Model already has a property on it to hold the currently selected Item and i would like to bind this to a DependancyProperty on the inner / child UserControl. I would then like to bind that DependancyProperty to a property on the child UserControl's View-Model. I can then set the DependancyProperty once in XAML with a binding expression and have the child UserControl do all its work in its View-Model like it should. The code i have looks like this.. Parent UserControl: <UserControl x:Class="ItemsListView" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" DataContext="{Binding Source={StaticResource ServiceLocator}, Path=ItemsListViewModel}">  <ItemDetailsView Item="{Binding Source={StaticResource ServiceLocator}, Path=ItemsListViewModel.SelectedItem}" /> </UserControl> Child UserControl: <UserControl x:Class="ItemDetailsView" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" DataContext="{Binding Source={StaticResource ServiceLocator}, Path=ItemDetailsViewModel}" ItemDetailsView.Item="{Binding Source={StaticResource ServiceLocator}, Path=ItemDetailsViewModel.Item, Mode=TwoWay}">  </UserControl> The selected Item is bound to the DependancyProperty fine. However from the DependancyProperty to the child View-Model does not. I've used this sort of apporach in a WPF app without problems. It appears to be a situation where there are two concurrent bindings which need to work but with the same target for two sources. Why won't the second (in the child UserControl) binding work?? Is there a way to acheive the behaviour I'm after?? Cheers.

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Vector insert() causes program to crash

- by wrongusername

This is the first part of a function I have that's causing my program to crash: vector<Student> sortGPA(vector<Student> student) { vector<Student> sorted; Student test = student[0]; cout << "here\n"; sorted.insert(student.begin(), student[0]); cout << "it failed.\n"; ... It crashes right at the sorted part because I can see "here" on the screen but not "it failed." The following error message comes up: Debug Assertion Failed! (a long path here...) Expression: vector emplace iterator outside range For more information on how your program can cause an assertion failure, see the Visual C++ documentation on asserts. I'm not sure what's causing the problem now, since I have a similar line of code elsewhere student.insert(student.begin() + position(temp, student), temp); that does not crash (where position returns an int and temp is another declaration of a struct Student). What can I do to resolve the problem, and how is the first insert different from the second one?

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Is there any way to filter certain things in pages served by IIS?

- by Ruslan

Hello, This is my first time posting here so please keep that in mind... I'll try to be short and get right to defining the problem. We have an ASP.NET 2 application (eCommerce package) running on IIS (Windows Server 2003). The main site's page(s) are using plain HTTP (no SSL), but the whole checkout process and the shopping cart page is using SSL (HTTPS). Now, the problem is that the site's header is located in a template file, and inside it it has a plain HTML 'img' tag calling an image with the "http://" portion hard-coded into it... This header appears on absolutely every page (including the https pages), and due to its insecure image tag, a warning box pops up in IE on every stage of the checkout process... Now, the problem: The live application cannot be touched in any way (no changes can be made to the template (so simply changing "http://" to "//" is not an option), IIS cannot be restarted, and the website/app pool cannot be restarted). Is there any way in the world (maybe plugin for IIS or a setting somewhere) that I can filter the pages right before they are served to replace the '<img src="http://example.com/image.jpg">' with '<img src="//example.com/image.jpg">' in the final HTML? Possibly via a regular expression or something? Thanks to everybody in advance.

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C++ Switch won't compile with externally defined variable used as case

- by C Nielsen

I'm writing C++ using the MinGW GNU compiler and the problem occurs when I try to use an externally defined integer variable as a case in a switch statement. I get the following compiler error: "case label does not reduce to an integer constant". Because I've defined the integer variable as extern I believe that it should compile, does anyone know what the problem may be? Below is an example: test.cpp #include <iostream> #include "x_def.h" int main() { std::cout << "Main Entered" << std::endl; switch(0) { case test_int: std::cout << "Case X" << std::endl; break; default: std::cout << "Case Default" << std::endl; break; } return 0; } x_def.h extern const int test_int; x_def.cpp const int test_int = 0; This code will compile correctly on Visual C++ 2008. Furthermore a Montanan friend of mine checked the ISO C++ standard and it appears that any const-integer expression should work. Is this possibly a compiler bug or have I missed something obvious? Here's my compiler version information: Reading specs from C:/MinGW/bin/../lib/gcc/mingw32/3.4.5/specs Configured with: ../gcc-3.4.5-20060117-3/configure --with-gcc --with-gnu-ld --with-gnu-as --host=mingw32 --target=mingw32 --prefix=/mingw --enable-threads --disable-nls --enable-languages=c,c++,f77,ada,objc,java --disable-win32-registry --disable-shared --enable-sjlj-exceptions --enable-libgcj --disable-java-awt --without-x --enable-java-gc=boehm --disable-libgcj-debug --enable-interpreter --enable-hash-synchronization --enable-libstdcxx-debug Thread model: win32 gcc version 3.4.5 (mingw-vista special r3)

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Event type property lost in IE-8

- by Channel72

I've noticed a strange Javascript error which only seems to happen on Internet Explorer 8. Basically, on IE-8 if you have an event handler function which captures the event object in a closure, the event "type" property seems to become invalidated from within the closure. Here's a simple code snippet which reproduces the error: <html> <head> <script type = "text/javascript"> function handleClickEvent(ev) { ev = (ev || window.event); alert(ev.type); window.setTimeout(function() { alert(ev.type); // Causes error on IE-8 }, 20); } function foo() { var query = document.getElementById("query"); query.onclick = handleClickEvent; } </script> </head> <body> <input id = "query" type = "submit"> <script type = "text/javascript"> foo(); </script> </body> </html> So basically, what happens here is that within the handleClickEvent function, we have the event object ev. We call alert(ev.type) and we see the event type is "click". So far, so good. But then when we capture the event object in a closure, and then call alert(ev.type) again from within the closure, now all of a sudden Internet Explorer 8 errors, saying "Member not found" because of the expression ev.type. It seems as though the type property of the event object is mysteriously gone after we capture the event object in a closure. I tested this code snippet on Firefox, Safari and Chrome, and none of them report an error condition. But in IE-8, the event object seems to become somehow invalidated after it's captured in the closure. Question: Why is this happening in IE-8, and is there any workaround?

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Prolog singleton variables in Python

- by Rubens

I'm working on a little set of scripts in python, and I came to this: line = "a b c d e f g" a, b, c, d, e, f, g = line.split() I'm quite aware of the fact that these are decisions taken during implementation, but shouldn't (or does) python offer something like: _, _, var_needed, _, _, another_var_needed, _ = line.split() as well as Prolog does offer, in order to exclude the famous singleton variables. I'm not sure, but wouldn't it avoid unnecessary allocation? Or creating references to the result of the split call does not count up as overhead? EDIT: Sorry, my point here is: in Prolog, as far as I'm concerned, in an expression like: test(L, N) :- test(L, 0, N). test([], N, N). test([_|T], M, N) :- V is M + 1, test(T, V, N). The variable represented by _ is not accessible, for what I suppose the reference to the value that does exist in the list [_|T] is not even created. But, in Python, if I use _, I can use the last value assigned to _, and also, I do suppose the assignment occurs for each of the variables _ -- which may be considered an overhead. My question here is if shouldn't there be (or if there is) a syntax to avoid such unnecessary attributions.

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Howto use predicates in LINQ to Entities for Entity Framework objects

- by user274947

I'm using LINQ to Entities for Entity Framework objects in my Data Access Layer. My goal is to filter as much as I can from the database, without applying filtering logic on in-memory results. For that purpose Business Logic Layer passes a predicate to Data Access Layer. I mean Func<MyEntity, bool> So, if I use this predicate directly, like public IQueryable<MyEntity> GetAllMatchedEntities(Func<MyEntity, Boolean> isMatched) { return qry = _Context.MyEntities.Where(x => isMatched(x)); } I'm getting the exception [System.NotSupportedException] --- {"The LINQ expression node type 'Invoke' is not supported in LINQ to Entities."} Solution in that question suggests to use AsExpandable() method from LINQKit library. But again, using public IQueryable<MyEntity> GetAllMatchedEntities(Func<MyEntity, Boolean> isMatched) { return qry = _Context.MyEntities.AsExpandable().Where(x => isMatched(x)); } I'm getting the exception Unable to cast object of type 'System.Linq.Expressions.FieldExpression' to type 'System.Linq.Expressions.LambdaExpression' Is there way to use predicate in LINQ to Entities query for Entity Framework objects, so that it is correctly transformed it into a SQL statement. Thank you.

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