Search Results

Search found 9889 results on 396 pages for 'behind the compiler'.

Page 324/396 | < Previous Page | 320 321 322 323 324 325 326 327 328 329 330 331  | Next Page >

• PHP Resize image down and crop using imagemagick

  - by mr12086

  I'm trying to downsize image uploaded by users at the time of upload. This is no problem but I want to get specific with sizes now. I'm looking for some advice on an algorithm im struggling to produce that will take any shape image - square or rectangle of any widths/heights and downsize it. This image needs to be downsized to a target box size (this changes but is stored in a variable).. So it needs to downsize the image so that both the width and height are larger than the width and height of the target maintaining aspect ratio. but only just.. The target size will be used to crop the image so there is no white space around the edges etc. I'm looking for just the algorithm behind creating the correct resize based on different dimension images - I can handle the cropping, even resizing in most cases but it fails in a few so i'm reaching out. I'm not really asking for PHP code more pseudo. Either is fine obviously. Thanks Kindly.

  Read the article

• Pointer Implementation Details in C

  - by Will Bickford

  I would like to know architectures which violate the assumptions I've listed below. Also I would like to know if any of the assumptions are false for all architectures (i.e. if any of them are just completely wrong). sizeof(int *) == sizeof(char *) == sizeof(void *) == sizeof(func_ptr *) The in-memory representation of all pointers for a given architecture is the same regardless of the data type pointed to. The in-memory representation of a pointer is the same as an integer of the same bit length as the architecture. Multiplication and division of pointer data types are only forbidden by the compiler. NOTE: Yes I know this is nonsensical. What I mean is - is there hardware support to forbid this incorrect usage? All pointer values can be casted to a single integer. In other words, what architectures still make use of segments and offsets? Incrementing a pointer is equivalent to adding sizeof(the pointed data type) to the memory address stored by the pointer. If p is an int32* then p+1 is equal to the memory address 4 bytes after p. I'm most used to pointers being used in a contiguous, virtual memory space. For that usage, I can generally get by thinking of them as addresses on a number line. See (http://stackoverflow.com/questions/1350471/pointer-comparison/1350488#1350488).

  Read the article

• VB.NET switching from ADO.NET to LINQ

  - by Cj Anderson

  I'm VERY new to Linq. I have an application I wrote that is in VB.NET 2.0. Works great, but I'd like to switch this application to Linq. I use ADO.NET to load XML into a datatable. The XML file has about 90,000 records in it. I then use the Datatable.Select to perform searches against that Datatable. The search control is a free form textbox. So if the user types in terms it searches instantly. Any further terms that are typed in continue to restrict the results. So you can type in Bob, or type in Bob Barker. Or type in Bob Barker Price is Right. The more criteria typed in the more narrowed your result. I bind the results to a gridview. Moving forward what all do I need to do? From a high level, I assume I need to: 1) Go to Project Properties -- Advanced Compiler Settings and change the Target framework to 3.5 from 2.0. 2) Add the reference to System.XML.Linq, Add the Imports statement to the classes. So I'm not sure what the best approach is going forward after that. I assume I use XDocument.Load, then my search subroutine runs against the XDocument. Do I just do the standard Linq query for this sort of repeated search? Like so: var people = from phonebook in doc.Root.Elements("phonebook") where phonebook.Element("userid") = "whatever" select phonebook; Any tips on how to best implement?

  Read the article

• How to choose light version of database system

  - by adopilot

  I am starting one POS (Point of sale) project. Targeting system is going to be written in C# .NET 2 WinForms and as main database server We are going to use MS-SQL Server. As we have a lot of POS devices in chain for one store I will love to have backend local data base system on each POS device. Scenario are following: When main server goes down!! POS application should continue working "off-line" with local database, until connection to main server come up again. Now I am in dilemma which local database is going to be most adoptable for me. Here is some notes for helping me point me in right direction: To be Light "My POS devices art usually old and suffering with performances" To be Free "I have a lot of devices and I do not wont additional cost beside main SQL serer" One day Ill love to try all that port on Mono and Linux OS. Here is what I've researched so far: Simple XML "Light but I am afraid of performance, My main table of items is average of 10K records" SQL-Express "I am afraid that my POS devices is poor with hardware for SQLExpress, and also hard to install on each device and configure" Less known Advantage Database Server have free distribution of offline ADT system. DBF with extended Library,"Respect for good old DBFs but that era is behind Me with clipper and DBFs" MS Access Sqlite "Mostly like for now, but I am afraid how it is going to pair with MS SQL do they have same Data types". I know that in this SO is a lot of subjective data, but at least can someone recommended some others lite database system, or things that I shod most take attention before I choice database.

  Read the article

• Why thread in background is not waiting for task to complete?

  - by Haris Hasan

  I am playing with async await feature of C#. Things work as expected when I use it with UI thread. But when I use it in a non-UI thread it doesn't work as expected. Consider the code below private void Click_Button(object sender, RoutedEventArgs e) { var bg = new BackgroundWorker(); bg.DoWork += BgDoWork; bg.RunWorkerCompleted += BgOnRunWorkerCompleted; bg.RunWorkerAsync(); } private void BgOnRunWorkerCompleted(object sender, RunWorkerCompletedEventArgs runWorkerCompletedEventArgs) { } private async void BgDoWork(object sender, DoWorkEventArgs doWorkEventArgs) { await Method(); } private static async Task Method() { for (int i = int.MinValue; i < int.MaxValue; i++) { var http = new HttpClient(); var tsk = await http.GetAsync("http://www.ebay.com"); } } When I execute this code, background thread don't wait for long running task in Method to complete. Instead it instantly executes the BgOnRunWorkerCompleted after calling Method. Why is that so? What am I missing here? P.S: I am not interested in alternate ways or correct ways of doing this. I want to know what is actually happening behind the scene in this case? Why is it not waiting?

  Read the article

• Potential g++ template bug?

  - by Evan Teran

  I've encountered some code which I think should compile, but doesn't. So I'm hoping some of the local standards experts here at SO can help :-). I basically have some code which resembles this: #include <iostream> template <class T = int> class A { public: class U { }; public: U f() const { return U(); } }; // test either the work around or the code I want... #ifndef USE_FIX template <class T> bool operator==(const typename A<T>::U &x, int y) { return true; } #else typedef A<int> AI; bool operator==(const AI::U &x, int y) { return true; } #endif int main() { A<int> a; std::cout << (a.f() == 1) << std::endl; } So, to describe what is going on here. I have a class template (A) which has an internal class (U) and at least one member function which can return an instance of that internal class (f()). Then I am attempting to create an operator== function which compares this internal type to some other type (in this case an int, but it doesn't seem to matter). When USE_FIX is not defined I get the following error: test.cc: In function 'int main()': test.cc:27:25: error: no match for 'operator==' in 'a.A<T>::f [with T = int]() == 1' Which seems odd, because I am clearly (I think) defining a templated operator== which should cover this, in fact if I just do a little of the work for the compiler (enable USE_FIX), then I no longer get an error. Unfortunately, the "fix" doesn't work generically, only for a specific instantiation of the template. Is this supposed to work as I expected? Or is this simply not allowed? BTW: if it matters I am using gcc 4.5.2.

  Read the article

• How do I install websocket module for Node.js on Debian VPS?

  - by Ollie Shaw

  I currently am renting a VPS from Dreamhost which runs Debian. I am still learning command line on this OS, but fast! I have successfully installed Node.js, now I want to install the websocket module found here: https://github.com/Worlize/WebSocket-Node From the root user, I have run the following command: npm install websocket The error thrown is: [websocket v1.0.7] Native code compile failed!! On Windows, native extensions require Visual Studio and Python. On Unix, native extensions require Python, make and a C++ compiler. Start npm with --websocket:verbose to show compilation output (if any). What commands should I issue to install this websocket module and its requirements? Thanks very much! Edit: When I run sudo apt-get install gcc make I get this message: Reading package lists... Done Building dependency tree Reading state information... Done gcc is already the newest version. gcc set to manually installed. make is already the newest version. 0 upgraded, 0 newly installed, 0 to remove and 44 not upgraded. And the same error when trying to install WebSocket.

  Read the article

• Why do mozilla and webkit prepend -moz- and -webkit- to CSS3 rules?

  - by egarcia

  CSS3 rules bring lots of interesting features. Take border-radius, for example. The standard says that if you write this rule: div.rounded-corners { border-radius: 5px; } I should get a 5px border radius. But neither mozilla nor webkit implement this. However, they implement the same thing, with the same parameters, with a different name (-moz-border-radius and -webkit-border-radius, respectively). In order to satisfy as many browsers as possible, you end up with this: div.rounded-corners { border-radius: 5px; -moz-border-radius: 5px; -webkit-border-radius: 5px; } I can see two obvious disadvantages: Copy-paste code. This has obvious risks that I will not discuss here. The W3C CSS validator will not validate these rules. At the same time, I don't see any obvious advantages. I believe that the people behind mozilla and webkit are more intelligent than myself. There must be some good reasons to have things structured this way. It's just that I can't see them. So, I must ask you people: why is this?

  Read the article

• Type result with Ternary operator in C#

  - by Vaccano

  I am trying to use the ternary operator, but I am getting hung up on the type it thinks the result should be. Below is an example that I have contrived to show the issue I am having: class Program { public static void OutputDateTime(DateTime? datetime) { Console.WriteLine(datetime); } public static bool IsDateTimeHappy(DateTime datetime) { if (DateTime.Compare(datetime, DateTime.Parse("1/1")) == 0) return true; return false; } static void Main(string[] args) { DateTime myDateTime = DateTime.Now; OutputDateTime(IsDateTimeHappy(myDateTime) ? null : myDateTime); Console.ReadLine(); ^ } | } | // This line has the compile issue ---------------+ On the line indicated above, I get the following compile error: Type of conditional expression cannot be determined because there is no implicit conversion between '< null ' and 'System.DateTime' I am confused because the parameter is a nullable type (DateTime?). Why does it need to convert at all? If it is null then use that, if it is a date time then use that. I was under the impression that: condition ? first_expression : second_expression; was the same as: if (condition) first_expression; else second_expression; Clearly this is not the case. What is the reasoning behind this? (NOTE: I know that if I make "myDateTime" a nullable DateTime then it will work. But why does it need it? As I stated earlier this is a contrived example. In my real example "myDateTime" is a data mapped value that cannot be made nullable.)

  Read the article

• Problem with UserControl with custom Dependency Property

  - by Mathias Koch

  Hi, I'm writing a user control with a dependency property for a search text called SearchText. It is a dependency property because I want to allow consumers of the control to use data binding. The user control contains a WPF TextBox where the user can enter the search text. I could use data binding to connect the SearchText dependency property of the user control with the Text dependency property of the TextBox, but this binding only fires when the text box looses input focus. What I want is SearchText to be updated after every change of Text. So I have added a TextChanged event handler to the user control where I set SearchText to the value of Text. My Problem is, the SearchText binding doesn't work, the source never gets updated. What am I doing wrong? Here's the relevant part of the user controls code-behind: public partial class UserControlSearchTextBox : UserControl { public string SearchText { get { return (string)GetValue(SearchTextProperty); } set { SetValue(SearchTextProperty, value); } } public static readonly DependencyProperty SearchTextProperty = DependencyProperty.Register("SearchText", typeof(string), typeof(UserControlSearchTextBox), new UIPropertyMetadata("")); private void TextBox_TextChanged(object sender, TextChangedEventArgs e) { SearchText = ((TextBox)sender).Text; } ... } The window that contains an instance of the user control has its DataContext set to an object that has a property also called SearchText. <uc:UserControlSearchTextBox SearchText="{Binding SearchText}" /> The data context of the Window: public class DataSourceUserManual : DataSourceBase { private string _searchText; public string SearchText { get { return _searchText; } set { _searchText = value; ... OnPropertyChanged("SearchText"); } } } Unfortunately, this setter is not called when I type into the text box. Any ideas?

  Read the article

• PDCurses TUI with C++ Win32 console application

  - by Bach

  I have downloaded pdcurses source and was able to successfully include curses.h in my project, linked the pre-compiled library and all good. After few hours of trying out the library, I saw the tuidemo.c in the demos folder, compiled it into an executable and brilliant! exactly what I needed for my project. Now the problem is that it's a C code, and I am working on a C++ project in VS c++ 2008. The files I need are tui.c and tui.h How can I include that C file in my C++ code? I saw few suggestions here but the compiler was not too happy with 100's of warnings and errors. How can I go on including/using that TUI pdcurses includes!? Thanks EDIT: I added extern "C" statement, so my test looks like this now, but I'm getting some other type of error #include <stdio.h> #include <stdlib.h> using namespace std; extern "C" { #include <tui.h> } void sub0(void) { //do nothing } void sub1(void) { //do nothing } int main (int argc, char * const argv[]) { menu MainMenu[] = { { "Asub", sub0, "Go inside first submenu" }, { "Bsub", sub1, "Go inside second submenu" }, { "", (FUNC)0, "" } /* always add this as the last item! */ }; startmenu(MainMenu, "TUI - 'textual user interface' demonstration program"); return 0; } Although it is compiling successfully, it is throwing an Error at runtime: 0xC0000005: Access violation reading location 0x021c52f9 at line startmenu(MainMenu, "TUI - 'textual user interface' demonstration program"); Not sure where to go from here. thanks again.

  Read the article

• how to templatize partial template specializations?

  - by Kyle

  I'm not even sure what title to give this question; hopefully the code will demonstrate what I'm trying to do: #include <string> #include <list> using namespace std; template<typename A> class Alpha { public: A m_alpha_a; }; template<typename B> class Bravo { public: B m_bravo_b; }; template<> class Alpha<string> { public: string m_alpha_string; }; template<typename B> template<> class Alpha<Bravo<B> > { public: Bravo<B> m_bravo_class; // Line A }; int main() { Alpha<int> alpha_int; alpha_int.m_alpha_a= 4; Alpha<string> alpha_string; alpha_string.m_alpha_string = "hi"; Alpha<Bravo<int> > alpha_bravo_int; alpha_bravo_int.m_bravo_class.m_bravo_b = 9; }; I want to write a specialization for Alpha<A> when A is of any type Bravo<B>, but the compiler says invalid explicit specialization before ‘’ token enclosing class templates are not explicitly specialized (Referring to // Line A.) What's the correct syntax to do what I want?

  Read the article

• calling template function without <>; type inference

  - by Oops

  Hi, if I have a function template with typename T, where the compiler can set the type by itself, I do not have to write the type explicitely when I call the function like: template < typename T > T min( T v1, T v2 ) { return ( v1 < v2 ) ? v1: v2; } int i1 = 1, i2 = 2; int i3 = min( i1, i2 ); //no explicit <type> but if I have a function template with two different typenames like... template < typename TOut, typename TIn > TOut round( TIn v ) { return (TOut)( v + 0.5 ); } double d = 1.54; int i = round<int>(d); //explicit <int> Is it true that I have to specify at least 1 typename, always? I assume the reason is because C++ can not distinguish functions between different return types, true? but if I use a void function and handover a reference, again I must not explicitely specify the return typename: template < typename TOut, typename TIn > void round( TOut & vret, TIn vin ) { vret = (TOut)(vin + 0.5); } double d = 1.54; int i; round(i, d); //no explicit <int> should the conclusion be to avoid functions with return and more prefer void functions that return via a reference when writing templates? Or is there a possibility to avoid explicitely writing the return type? something like "type inference" for templates... is "type inference" possible in C++0x? I hope I was not too unclear. many thanks in advance Oops

  Read the article

• Passing Multiple values Through Query String?

  - by Googler

  Hi all, I tried to pass more than one value through Query String from page1.aspx to page2.aspx. This is my Query string in the Grid View <a href="javascript:void(0);" onclick='javascript:window.open("Update.aspx?Regno= <%#Eval ("ID") %>'+ ","'&Fn=<%#Eval ("FIRSTNAME") %>' +", "'&Ln=<%#Eval ("LASTNAME") %>'")';> Edit</a> On My Page2.aspx, my code behind on PageLoad is: if (Page.IsPostBack) return; string id = Request.QueryString["ID"]; string Firstname = Request.QueryString["FIRSTNAME"]; string LastName = Request.QueryString["LASTNAME"]; My Visual Studio IDE shows a syntax error on this query string. I dont know the exact way to pass multiple values through Query String. How to make it work? Can anyone pls help me on this.. Which is the right syntax to pass multiple query string?

  Read the article

• Pass Parameter to Subroutine in Codebehind

  - by Sanjubaba

  I'm trying to pass an ID of an activity (RefNum) to a Sub in my codebehind. I know I'm supposed to use parentheses when passing parameters to subroutines and methods, and I've tried a number of ways and keep receiving the following error: BC30203: Identifier expected. I'm hard-coding it on the front-end just to try to get it to pass [ OnDataBound="FillSectorCBList("""WK.002""")" ], but it's obviously wrong. :( Front-end: <asp:DetailsView ID="dvEditActivity" AutoGenerateRows="False" DataKeyNames="RefNum" OnDataBound="dvSectorID_DataBound" OnItemUpdated="dvEditActivity_ItemUpdated" DataSourceID="dsEditActivity" > <Fields> <asp:TemplateField> <ItemTemplate> <br /><span style="color:#0e85c1;font-weight:bold">Sector</span><br /><br /> <asp:CheckBoxList ID="cblistSector" runat="server" DataSourceID="dsGetSectorNames" DataTextField="SectorName" DataValueField="SectorID" OnDataBound="FillSectorCBList("""WK.002""")" ></asp:CheckBoxList> <%-- Datasource to populate cblistSector --%> <asp:SqlDataSource ID="dsGetSectorNames" runat="server" ConnectionString="<%$ ConnectionStrings:dbConn %>" ProviderName="<%$ ConnectionStrings:dbConn.ProviderName %>" SelectCommand="SELECT SectorID, SectorName from Sector ORDER BY SectorID"></asp:SqlDataSource> </ItemTemplate> </asp:TemplateField> </Fields> </asp:DetailsView> Code-behind: Sub FillSectorCBList(ByVal RefNum As String, ByVal sender As Object, ByVal e As System.EventArgs) Dim SectorIDs As New ListItem Dim myConnection As String = ConfigurationManager.ConnectionStrings("dbConn").ConnectionString() Dim objConn As New SqlConnection(myConnection) Dim strSQL As String = "SELECT DISTINCT A.RefNum, AS1.SectorID, S.SectorName FROM Activity A LEFT OUTER JOIN Activity_Sector AS1 ON AS1.RefNum = A.RefNum LEFT OUTER JOIN Sector S ON AS1.SectorID = S.SectorID WHERE A.RefNum = @RefNum ORDER BY A.RefNum" Dim objCommand As New SqlCommand(strSQL, objConn) objCommand.Parameters.AddWithValue("RefNum", RefNum) Dim ad As New SqlDataAdapter(objCommand) Try [Code] Finally [Code] End Try objCommand.Connection.Close() objCommand.Dispose() objConn.Close() End Sub Any advice would be great. I'm not sure if I even have the right approach. Thank you!

  Read the article

• Collision detections and how efficient they are

  - by Shadow

  How exactly do you implement collision detection? What are the costs involved? Do different platforms(c/c++, java, cocoa/iphone, flash, directX) have different optimizations for calculating collisions. And lastly are there libraries available to do this for me, or some that I can just interpret for my platform of choice? As I understand it you would need to loop through the collision map and find the area in question and then compair the input thing(e.g. a sprite) to the type of pixel that is in the questioned area. I understand the very basic idea, but I don't understand the underlying implementation or even a higher level one for that matter. It would seem that this type of detection, or any for that matter, is very costly. Tile map? Bit array? How are these created from an image(I would guess looping and doing stuff)? The reason I ask this question is to get a better understanding of the efficiency behind the scenes and to understand exactly what is going on. Links, references, or examples would be very helpful. I know this question is a bit longwinded so any help or references would be very welcome. Thanks SO!

  Read the article

• A monkey could do this better - Access to and availability of private member functions in C++

  - by David

  I am wandering the desert of my brain. I'm trying to write something like the following: class MyClass { // Peripherally Related Stuff public: void TakeAnAction(int oneThing, int anotherThing) { switch(oneThing){ case THING_A: TakeThisActionWith(anotherThing); break; //cases THINGS_NOT_A: }; private: void TakeThisActionWith(int thing) { string outcome = new string; outcome = LookUpOutcome(thing); // Do some stuff based on outcome return; } string LookUpOutcome(int key) { string oc = new string; oc = MyPrivateMap[key]; return oc; } map<int, string> MyPrivateMap; Then in the .cc file where I am actually using these things, while compiling the TakeAnAction section, it [CC, the solaris compiler] throws an an error: 'The function LookUpOutcome must have a prototype' and bombs out. In my header file, I have declared 'string LookUpOutcome(int key);' in the private section of the class. I have tried all sorts of variations. I tried to use 'this' for a little while, and it gave me 'Can only use this in non-static member function.' Sadly, I haven't declared anything static and these are all, putatively, member functions. I tried it [on TakeAnAction and LookUp] when I got the error, but I got something like, 'Can't access MyPrivateMap from LookUp'. MyPrivateMap could be made public and I could refer to it directly, I guess, but my sensibility says that is not the right way to go about this [that means that namespace scoped helper functions are out, I think]. I also guess I could just inline the lookup and subsequent other stuff, but my line-o-meter goes on tilt. I'm trying desperately not to kludge it.

  Read the article

• Emulating Visual Studio's Web Application "publish" at the command line

  - by cbp

  Hi, I am trying to automate my deployment process and am now thoroughly confused. I know that there are many questions on stackoverflow about this, but they all have different solutions and none of them work. I have a Web Application project which I usually publish by right-clicking and selecting "Publish". I get a dialog box where I use the following options: Build configuration: Release Publish method: File system Target location: C:\Deployments\MyWebsite Replace matching files with local copies I should mention that in the properties of the project I have "Items to deploy" set to "Only files needed to run this application". After running this, my entire solution is built, dependencies are resolved, build events are run, web.config transformations are applied and the website is copied to C:\Deployments\MyWebsite, although non-required files such as code-behind files are not copied. I have not been able to replicate this... in fact at this stage I'm not even sure which command line tool am I supposed to be using - msbuild, msdeploy or aspnet_compiler? This guy asks almost the same question but his solution doesn't work at all. For example, build events do not run correctly because the macros are not resolved. Whats more, the files do not get copied into the correct directory at all... I can't even begin to explain what happens!

  Read the article

• LuaEdit can't find module when Lua files all in the same folder

  - by joverboard

  I downloaded LuaEdit to use as an IDE and debug tool however I'm having trouble using it for even the simplest things. I've created a solution with 2 files in it, all of which are stored in the same folder. My files are as follows: --startup.lua require("foo") test("Testing", "testing", "one, two, three") --foo.lua foo = {} print("In foo.lua") function test(a,b,c) print(a,b,c) end This works fine when in my C++ compiler when accessed through some embed code, however when I attempt to use the same code in LuaEdit, it crashes on line 3 require("foo") with an error stating: module 'foo' not found: no field package.preload['foo'] no file 'C:\Program Files (x86)\LuaEdit 2010\lua\foo.lua' no file 'C:\Program Files (x86)\LuaEdit 2010\lua\foo\init.lua' no file 'C:\Program Files (x86)\LuaEdit 2010\foo.lua' no file 'C:\Program Files (x86)\LuaEdit 2010\foo\init.lua' no file '.\foo.lua' no file 'C:\Program Files (x86)\LuaEdit 2010\foo.dll' no file 'C:\Program Files (x86)\LuaEdit 2010\loadall.dll' no file '.\battle.dll' I have also tried creating these files prior to adding them to a solution and still get the same error. Is there some setting I'm missing? It would be great to have an IDE/debugger but it's useless to me if it can't run linked functions.

  Read the article

• Explicit localization problem

  - by X-Dev

  when trying to translate the confirmation message to Norwegian i get the following error: Cannot have more than one binding on property 'OnClientClick' on 'System.Web.UI.WebControls.LinkButton'. Ensure that this property is not bound through an implicit expression, for example, using meta:resourcekey. i use Explicit localization in the following manner: <asp:LinkButton ID="lnkMarkInvoiced" runat="server" OnClick="lnkMarkInvoiced_OnClick" OnClientClick="<%# Resources: lnkMarkInvoicedResource.OnClientClick%>" Visible="False" CssClass="stdtext" meta:resourcekey="lnkMarkInvoicedResource" ></asp:LinkButton> here's the local resource file entry: <data name="lnkMarkInvoicedResource.OnClientClick" xml:space="preserve"> <value>return confirm('Er du sikker?');</value> if i remove the meta attribute i get the English text(default). how do i get the Norwegian text appearing without resorting to using the code behind? Update: removing the meta attribute prevents the exception from occurring but the original problem still exists. I can't get the Norwegian text to show. only the default English text shows. Another Update: I know this question is getting old but i still can't get the Norwegian text to display. If anyone has some tips please post a response.

  Read the article

• Why does one of these statements compile in Scala but not the other?

  - by Jeff

  (Note: I'm using Scala 2.7.7 here, not 2.8). I'm doing something pretty simple -- creating a map based on the values in a simple, 2-column CSV file -- and I've completed it easily enough, but I'm perplexed at why my first attempt didn't compile. Here's the code: // Returns Iterator[String] private def getLines = Source.fromFile(csvFilePath).getLines // This doesn't compile: def mapping: Map[String,String] = { Map(getLines map { line: String => val pairArr = line.split(",") pairArr(0) -> pairArr(1).trim() }.toList:_*) } // This DOES compile def mapping: Map[String,String] = { def strPair(line: String): (String,String) = { val pairArr = line.split(",") pairArr(0) -> pairArr(1).trim() } Map(getLines.map( strPair(_) ).toList:_*) } The compiler error is CsvReader.scala:16: error: value toList is not a member of (St ring) = (java.lang.String, java.lang.String) [scalac] possible cause: maybe a semicolon is missing before `value toList'? [scalac] }.toList:_*) [scalac] ^ [scalac] one error found So what gives? They seem like they should be equivalent to me, apart from the explicit function definition (vs. anonymous in the nonworking example) and () vs. {}. If I replace the curly braces with parentheses in the nonworking example, the error is "';' expected, but 'val' found." But if I remove the local variable definition and split the string twice AND use parens instead of curly braces, it compiles. Can someone explain this difference to me, preferably with a link to Scala docs explaining the difference between parens and curly braces when used to surround method arguments?

  Read the article

• Destructors not called when native (C++) exception propagates to CLR component

  - by Phil Nash

  We have a large body of native C++ code, compliled into DLLs. Then we have a couple of dlls containing C++/CLI proxy code to wrap the C++ interfaces. On top of that we have C# code calling into the C++/CLI wrappers. Standard stuff, so far. But we have a lot of cases where native C++ exceptions are allowed to propagate to the .Net world and we rely on .Net's ability to wrap these as System.Exception objects and for the most part this works fine. However we have been finding that destructors of objects in scope at the point of the throw are not being invoked when the exception propagates! After some research we found that this is a fairly well known issue. However the solutions/ workarounds seem less consistent. We did find that if the native code is compiled with /EHa instead of /EHsc the issue disappears (at least in our test case it did). However we would much prefer to use /EHsc as we translate SEH exceptions to C++ exceptions ourselves and we would rather allow the compiler more scope for optimisation. Are there any other workarounds for this issue - other than wrapping every call across the native-managed boundary in a (native) try-catch-throw (in addition to the C++/CLI layer)?

  Read the article

• Why are my Flex resource bundles not being loaded?

  - by Chris R

  I have an Actionscript module in the flex source folder filterModules, which is one of two additional source folders in my project (the main source folder is reports, but I'm not dealing with anything in there right now). Here's the MXML content that references the resources. ... This array is assigned to the dataProvider field of a ComboBox. It's not bound using the bindings, presumably for reasons that made sense to the original developer, and it'd be nontrivial to change the class to make that happen. I additionally have a resource property file in a folder resources/en_US and I have the source folder resources/{locale} in the project source settings. My additional compiler options are -locale en_US. The resource property file is resources/en_US/labels.properties (All paths are relative to the flash builder project root) and contains (amongst other things) these keys: metric.q3 = Overall Satisfaction metric.q5 = Personnel metric.q9a = Issue Resolution metric.q42 = Visit Duration Sat metric.q34 = Visit Duration I have written some FlexUnit tests that run in my local Flash Player that exercise these resources -- they check that every label is represented in the metrics array, for example, so I know that the resource file is loaded when run locally. However, when I copy the module .swf file over to my server, the combo box to which the array is assigned is empty. I copy the .swf like so, if it matters: rsync -rlDv --inplace -T /tmp ~/projects/flex_reports/bin-debug/rankingFilter.swf HOSTNAME:WEBROOT/flashPath/ Why is this? I am not able to debug the remote module because our surrounding site sets up a lot of context and makes some database calls to determine which module to load. I'm hoping to get some pointers on why resource bundles might not show up. I'd understand it if the array was present with wrong labels, but the array is instead completely empty, which is pretty odd.

  Read the article

• Why is the ASP.NET Repeater.Items collection empty, when controls are on the screen?

  - by Ryan

  I have an ASP page with the following repeater: <asp:Repeater runat="server" ID="RegionRepeater" DataSourceID="SqlDataSourceRegions" EnableViewState="true"> <ItemTemplate> <tr> <td valign="top"> <b><%#Eval("description")%></b> <asp:HiddenField runat="server" ID="RegionID" Value='<%#Eval("region_id")%>'/> </td> <td> <asp:FileUpload ID="FileUpload" runat="server" Width="368px" /> </td> </tr> </ItemTemplate> </asp:Repeater> (The repeater is inside a Wizard, inside a content pane). The code behind is connected to the protected void Wizard1_NextButtonClick(object sender, WizardNavigationEventArgs e) event. There are two items on the screen (two rows inside the table). However, when the code tries to read those items, the Items collection is empty! foreach(RepeaterItem region in RegionRepeater.Items) { // Never runs - the RegionRepeater.Items.Count = 0 FileUpload fileUpload = (FileUpload) region.FindControl("FileUpload"); String regionID = ((HiddenField)region.FindControl("RegionID")).Value; ... Why is the collection empty, when there are controls drawn on the screen? Thanks a lot for any help; this is starting to drive me nuts. (BTW: I tried adding/removing the EnableViewState="true" tag)

  Read the article

• Divide and conquer of large objects for GC performance

  - by Aperion

  At my work we're discussing different approaches to cleaning up a large amount of managed ~50-100MB memory.There are two approaches on the table (read: two senior devs can't agree) and not having the experience the rest of the team is unsure of what approach is more desirable, performance or maintainability. The data being collected is many small items, ~30000 which in turn contains other items, all objects are managed. There is a lot of references between these objects including event handlers but not to outside objects. We'll call this large group of objects and references as a single entity called a blob. Approach #1: Make sure all references to objects in the blob are severed and let the GC handle the blob and all the connections. Approach #2: Implement IDisposable on these objects then call dispose on these objects and set references to Nothing and remove handlers. The theory behind the second approach is since the large longer lived objects take longer to cleanup in the GC. So, by cutting the large objects into smaller bite size morsels the garbage collector will processes them faster, thus a performance gain. So I think the basic question is this: Does breaking apart large groups of interconnected objects optimize data for garbage collection or is better to keep them together and rely on the garbage collection algorithms to processes the data for you? I feel this is a case of pre-optimization, but I do not know enough of the GC to know what does help or hinder it.

  Read the article

< Previous Page | 320 321 322 323 324 325 326 327 328 329 330 331  | Next Page >