Search Results

Search found 42627 results on 1706 pages for 'type conversion'.

Page 4/1706 | < Previous Page | 1 2 3 4 5 6 7 8 9 10 11 12  | Next Page >

  • Can't find which row is causing conversion error

    - by Marwan
    I have the following table: CREATE TABLE [dbo].[Accounts1]( [AccountId] [nvarchar](50) NULL, [ExpiryDate] [nvarchar](50) NULL ) I am trying to convert nvarchar to datetime using this query: select convert(datetime, expirydate) from accounts I get this error: Conversion failed when converting datetime from character string. The status bar says "2390 rows". I go to rows 2390, 2391 and 2392. There is nothing wrong with the data there. I even try to convert those particular rows and it works. How can I find out which row(s) is causing the conversion error?

    Read the article

  • Data loss between conversion

    - by Alex Brooks
    Why is it that I loose data between the conversions below even though both types take up the same amount of space? If the conversion was done bitwise, it should be true that x = z unless data is being stripped during the conversion, right? Is there a way to do the two conversions without losing data (i.e. so that x = z)? main.cpp: #include <stdio.h> #include <stdint.h> int main() { double x = 5.5; uint64_t y = static_cast<uint64_t>(x); double z = static_cast<double>(y) // Desire : z = 5.5; printf("Size of double: %lu\nSize of uint64_t: %lu\n", sizeof(double), sizeof(uint64_t)); printf("%f\n%lu\n%f\n", x, y, z); } Results: Size of double: 8 Size of uint64_t: 8 5.500000 5 5.000000

    Read the article

  • Easy way for Crystal Reports to MS SQL Server Reporting Services conversion

    - by scoob
    Is there a way to easily convert Crystal Reports reports to Reporting Services RDL format? We have quite a few reports that will be needing conversion soon. I know about the manual process (which is basically rebuilding all your reports from scratch in SSRS), but my searches pointed to a few possibilities with automatic conversion "acceleration" with several consulting firms. (As described on http://www.microsoft.com/sql/technologies/reporting/partners/crystal-migration.mspx). Do any of you have any valid experiences or recomendations regarding this particular issue? Are there any tools around that I do not know about?

    Read the article

  • Should I convert my AAC M4A files to MP3?

    - by j0rd4n
    Due to Apple, I have a large majority of my music files in the AAC M4A format. They do NOT have DRM so I don't have to worry about that. I'm getting tired of Apple products and really want to switch to a different brand player (and something more compatible with Linux). It appears most MP3 players support...well...MP3 and not AAC. Should I convert my library to be free of Apple and open to other players? Is this a lossless conversion? Can it be lossless? If I will lose quality, I'm not interested. Am I even doing the right thing? AAC is the better format, but I'm not seeing a lot of support for it yet. I'll be honest and say that I need some education in this department. Any helpful advice is most welcome.

    Read the article

  • Intel RAID0 on Windows 8 not Displaying Correct Media Type

    - by kobaltz
    I have my primary C Drive which consists of 2 Intel 120GB SSD Drives in a RAID0. I have a clean install of Windows 8 Pro, latest MEI software, latest RST software, latest Intel Toolbox. Prior to this I had installed Windows 8 Pro as an upgrade. When I went into the Optimize Drives while in the Upgrade installation, it showed the Media Types as Solid State Drives. However, now since I am in a brand new install, it is showing the Media Type as Hard Disk Drive. I am worried about this because of the trim not working properly. Before when in the upgrade, it showed SSD as the media type and the Optimize option would perform a manual trim. Unfortunately, my search credentials on Google are so common to many other things (ie Raid0, SSD, Windows 8, Media Type) that all I am finding are useless topics. Before, (found on random site) it showed the Media Type as below

    Read the article

  • [.Net/Reflection] Getting the .Net corresponding type of a C# type

    - by Serious
    Hello, is there a function that, given a C# type's string representation, returns the corresponding .Net type or .Net type's string representation; or any way to achieve this. For example : "bool" - System.Boolean or "System.Boolean" "int" - System.Int32 or "System.Int32" ... Thanks. Edit : really sorry, it's not a "type to type" mapping that I wish but either a "string to string" mapping or a "string to type" mapping.

    Read the article

  • Partial generic type inference possible in C#?

    - by Lasse V. Karlsen
    I am working on rewriting my fluent interface for my IoC class library, and when I refactored some code in order to share some common functionality through a base class, I hit upon a snag. Note: This is something I want to do, not something I have to do. If I have to make do with a different syntax, I will, but if anyone has an idea on how to make my code compile the way I want it, it would be most welcome. I want some extension methods to be available for a specific base-class, and these methods should be generic, with one generic type, related to an argument to the method, but the methods should also return a specific type related to the particular descendant they're invoked upon. Better with a code example than the above description methinks. Here's a simple and complete example of what doesn't work: using System; namespace ConsoleApplication16 { public class ParameterizedRegistrationBase { } public class ConcreteTypeRegistration : ParameterizedRegistrationBase { public void SomethingConcrete() { } } public class DelegateRegistration : ParameterizedRegistrationBase { public void SomethingDelegated() { } } public static class Extensions { public static ParameterizedRegistrationBase Parameter<T>( this ParameterizedRegistrationBase p, string name, T value) { return p; } } class Program { static void Main(string[] args) { ConcreteTypeRegistration ct = new ConcreteTypeRegistration(); ct .Parameter<int>("age", 20) .SomethingConcrete(); // <-- this is not available DelegateRegistration del = new DelegateRegistration(); del .Parameter<int>("age", 20) .SomethingDelegated(); // <-- neither is this } } } If you compile this, you'll get: 'ConsoleApplication16.ParameterizedRegistrationBase' does not contain a definition for 'SomethingConcrete' and no extension method 'SomethingConcrete'... 'ConsoleApplication16.ParameterizedRegistrationBase' does not contain a definition for 'SomethingDelegated' and no extension method 'SomethingDelegated'... What I want is for the extension method (Parameter<T>) to be able to be invoked on both ConcreteTypeRegistration and DelegateRegistration, and in both cases the return type should match the type the extension was invoked on. The problem is as follows: I would like to write: ct.Parameter<string>("name", "Lasse") ^------^ notice only one generic argument but also that Parameter<T> returns an object of the same type it was invoked on, which means: ct.Parameter<string>("name", "Lasse").SomethingConcrete(); ^ ^-------+-------^ | | +---------------------------------------------+ .SomethingConcrete comes from the object in "ct" which in this case is of type ConcreteTypeRegistration Is there any way I can trick the compiler into making this leap for me? If I add two generic type arguments to the Parameter method, type inference forces me to either provide both, or none, which means this: public static TReg Parameter<TReg, T>( this TReg p, string name, T value) where TReg : ParameterizedRegistrationBase gives me this: Using the generic method 'ConsoleApplication16.Extensions.Parameter<TReg,T>(TReg, string, T)' requires 2 type arguments Using the generic method 'ConsoleApplication16.Extensions.Parameter<TReg,T>(TReg, string, T)' requires 2 type arguments Which is just as bad. I can easily restructure the classes, or even make the methods non-extension-methods by introducing them into the hierarchy, but my question is if I can avoid having to duplicate the methods for the two descendants, and in some way declare them only once, for the base class. Let me rephrase that. Is there a way to change the classes in the first code example above, so that the syntax in the Main-method can be kept, without duplicating the methods in question? The code will have to be compatible with both C# 3.0 and 4.0. Edit: The reason I'd rather not leave both generic type arguments to inference is that for some services, I want to specify a parameter value for a constructor parameter that is of one type, but pass in a value that is a descendant. For the moment, matching of specified argument values and the correct constructor to call is done using both the name and the type of the argument. Let me give an example: ServiceContainerBuilder.Register<ISomeService>(r => r .From(f => f.ConcreteType<FileService>(ct => ct .Parameter<Stream>("source", new FileStream(...))))); ^--+---^ ^---+----^ | | | +- has to be a descendant of Stream | +- has to match constructor of FileService If I leave both to type inference, the parameter type will be FileStream, not Stream.

    Read the article

  • Type casting in C++ by detecting the current 'this' object type

    - by Elroy
    My question is related to RTTI in C++ where I'm trying to check if an object belongs to the type hierarchy of another object. The BelongsTo() method checks this. I tried using typeid, but it throws an error and I'm not sure about any other way how I can find the target type to convert to at runtime. #include <iostream> #include <typeinfo> class X { public: // Checks if the input type belongs to the type heirarchy of input object type bool BelongsTo(X* p_a) { // I'm trying to check if the current (this) type belongs to the same type // hierarchy as the input type return dynamic_cast<typeid(*p_a)*>(this) != NULL; // error C2059: syntax error 'typeid' } }; class A : public X { }; class B : public A { }; class C : public A { }; int main() { X* a = new A(); X* b = new B(); X* c = new C(); bool test1 = b->BelongsTo(a); // should return true bool test2 = b->BelongsTo(c); // should return false bool test3 = c->BelongsTo(a); // should return true } Making the method virtual and letting derived classes do it seems like a bad idea as I have a lot of classes in the same type hierarchy. Or does anybody know of any other/better way to the do the same thing? Please suggest.

    Read the article

  • Getting the type of an array of T, without specifying T - Type.GetType("T[]")

    - by Merlyn Morgan-Graham
    I am trying to create a type that refers to an array of a generic type, without specifying the generic type. That is, I would like to do the equivalent of Type.GetType("T[]"). I already know how to do this with a non-array type. E.g. Type.GetType("System.Collections.Generic.IEnumerable`1") // or typeof(IEnumerable<>) Here's some sample code that reproduces the problem. using System; using System.Collections.Generic; public class Program { public static void SomeFunc<T>(IEnumerable<T> collection) { } public static void SomeArrayFunc<T>(T[] collection) { } static void Main(string[] args) { Action<Type> printType = t => Console.WriteLine(t != null ? t.ToString() : "(null)"); Action<string> printFirstParameterType = methodName => printType( typeof(Program).GetMethod(methodName).GetParameters()[0].ParameterType ); printFirstParameterType("SomeFunc"); printFirstParameterType("SomeArrayFunc"); var iEnumerableT = Type.GetType("System.Collections.Generic.IEnumerable`1"); printType(iEnumerableT); var iEnumerableTFromTypeof = typeof(IEnumerable<>); printType(iEnumerableTFromTypeof); var arrayOfT = Type.GetType("T[]"); printType(arrayOfT); // Prints "(null)" // ... not even sure where to start for typeof(T[]) } } The output is: System.Collections.Generic.IEnumerable`1[T] T[] System.Collections.Generic.IEnumerable`1[T] System.Collections.Generic.IEnumerable`1[T] (null) I'd like to correct that last "(null)". This will be used to get an overload of a function via reflections by specifying the method signature: var someMethod = someType.GetMethod("MethodName", new[] { typeOfArrayOfT }); // ... call someMethod.MakeGenericMethod some time later I've already gotten my code mostly working by filtering the result of GetMethods(), so this is more of an exercise in knowledge and understanding.

    Read the article

  • Error while conversion of string to datetime

    - by aswathi
    The conversion of a char data type to a DateTime data type resulted in an out-of-range DateTime value. The statement has been terminated. Please give me most possible answers ALTER PROCEDURE [dbo].[attendance_updatebyemployee_id] @Employee_id int, @AtDate datetime, @FNLogged bit, @ANLogged bit, @LogTime varchar(10), @LogOuttime varchar(10) AS BEGIN SET NOCOUNT ON; update Mst_Attendance set FNLogged=@FNLogged, ANLogged=@ANLogged,LogTime=@LogTime,LogOuttime=@LogOuttime where EmployeeId=@Employee_id and Atdate= @AtDate END

    Read the article

  • serializing type definitions?

    - by Dave
    I'm not positive I'm going about this the right way. I've got a suite of applications that have varying types of output (custom defined types). For example, I might have a type called Widget: Class Widget Public name as String End Class Throughout the course of operation, when a user experiences a certain condition, the application will take that output instance of widget that user received, serialize it, and log it to the database noting the name of the type. Now, I have other applications that do something similar, but instead of dealing with Widget, it could be some totally random other type with different attributes, but again I serialize the instance, log it to the db, and note the name of the type. I have maybe a half dozen different types and don't anticipate too many additional ones in the future. After all this is said and done, I have an admin interface that looks through these logs, and has the ability for the user to view the contents of this data thats been logged. The Admin app has a reference to all the types involved, and with some basic switch case logic hinged upon the name of the type, will cast it into their original types, and pass it on to some handlers that have basic display logic to spit the data back out in a readable format (one display handler for each type) NOW... all this is well and good... Until one day, my model changed. The Widget class now has deprecated the name attribute and added on a bunch of other attributes. I will of course get type mismatches in the admin side when I try to reconstitute this data. I was wondering if there was some way, at runtime, i could perhaps reflect through my code and get a snapshot of the type definition at that precise moment, serialize it, and store it along with the data so that I could somehow use this to reconstitute it in the future?

    Read the article

  • What can Haskell's type system do that Java's can't?

    - by Matt Fenwick
    I was talking to a friend about the differences between the type systems of Haskell and Java. He asked me what Haskell's could do that Java's couldn't, and I realized that I didn't know. After thinking for a while, I came up with a very short list of minor differences. Not being heavy into type theory, I'm left wondering whether they're formally equivalent. To try and keep this from becoming a subjective question, I'm asking: what are the major, non-syntactical differences between their type systems? I realize some things are easier/harder in one than in the other, and I'm not interested in talking about those. And to make it more specific, let's ignore Haskell type extensions since there's so many out there that do all kinds of crazy/cool stuff.

    Read the article

  • What can Haskell's type system do that Java's can't and vice versa?

    - by Matt Fenwick
    I was talking to a friend about the differences between the type systems of Haskell and Java. He asked me what Haskell's could do that Java's couldn't, and I realized that I didn't know. After thinking for a while, I came up with a very short list of minor differences. Not being heavy into type theory, I'm left wondering whether they're formally equivalent. To try and keep this from becoming a subjective question, I'm asking: what are the major, non-syntactical differences between their type systems? I realize some things are easier/harder in one than in the other, and I'm not interested in talking about those. And to make it more specific, let's ignore Haskell type extensions since there's so many out there that do all kinds of crazy/cool stuff.

    Read the article

  • What are some reasonable stylistic limits on type inference?

    - by Jon Purdy
    C++0x adds pretty darn comprehensive type inference support. I'm sorely tempted to use it everywhere possible to avoid undue repetition, but I'm wondering if removing explicit type information all over the place is such a good idea. Consider this rather contrived example: Foo.h: #include <set> class Foo { private: static std::set<Foo*> instances; public: Foo(); ~Foo(); // What does it return? Who cares! Just forward it! static decltype(instances.begin()) begin() { return instances.begin(); } static decltype(instances.end()) end() { return instances.end(); } }; Foo.cpp: #include <Foo.h> #include <Bar.h> // The type need only be specified in one location! // But I do have to open the header to find out what it actually is. decltype(Foo::instances) Foo::instances; Foo() { // What is the type of x? auto x = Bar::get_something(); // What does do_something() return? auto y = x.do_something(*this); // Well, it's convertible to bool somehow... if (!y) throw "a constant, old school"; instances.insert(this); } ~Foo() { instances.erase(this); } Would you say this is reasonable, or is it completely ridiculous? After all, especially if you're used to developing in a dynamic language, you don't really need to care all that much about the types of things, and can trust that the compiler will catch any egregious abuses of the type system. But for those of you that rely on editor support for method signatures, you're out of luck, so using this style in a library interface is probably really bad practice. I find that writing things with all possible types implicit actually makes my code a lot easier for me to follow, because it removes nearly all of the usual clutter of C++. Your mileage may, of course, vary, and that's what I'm interested in hearing about. What are the specific advantages and disadvantages to radical use of type inference?

    Read the article

  • Automatic type conversion in Java?

    - by davr
    Is there a way to do automatic implicit type conversion in Java? For example, say I have two types, 'FooSet' and 'BarSet' which both are representations of a Set. It is easy to convert between the types, such that I have written two utility methods: /** Given a BarSet, returns a FooSet */ public FooSet barTOfoo(BarSet input) { /* ... */ } /** Given a FooSet, returns a BarSet */ public BarSet fooTObar(FooSet input) { /* ... */ } Now say there's a method like this that I want to call: public void doSomething(FooSet data) { /* .. */ } But all I have is a BarSet myBarSet...it means extra typing, like: doSomething(barTOfoo(myBarSet)); Is there a way to tell the compiler that certain types can automatically be cast to other types? I know this is possible in C++ with overloading, but I can't find a way in Java. I want to just be able to type: doSomething(myBarSet); And the compiler knows to automatically call barTOfoo()

    Read the article

  • cvs to mercurial conversion gets tags wrong

    - by Mark Borgerding
    I've tried all the recommended conversion techniques Mostly they manage to get the latest version of the files right, but every one of them trashes my history. Many (most?) of the tags from my cvs project have at least one file in error when I run "hg up $tag" My cvs repo is not all that complicated. Why can't anything convert it? I'd like to dump cvs and convert to mercurial, but not without history. To recap my frustration: I tried hg convert (tried --branchsort,--timesort, fuzz=0) I tried cvs2svn and then hg convert. tailor does not work with recent versions of mercurial fromcvs disappeared from the face of the earth hg-cvs-import has been abandoned for 4 years and doesn't work with recent versions of hg I have tried using the two most recent versions of mercurial ( 1.5 and 1.5.1 ).

    Read the article

  • JSP/JSF conversion to ASP.NET

    - by sharru
    I have a pretty big JSF web application. I must convert the application to ASP.NET. I already converted the Java code to C# code manually and also using JCLA (Java Language Conversion Assistant from Microsoft). What is the best way to convert the JSF part to ASP.NET? Is there any tool that can help shorten the work? For example convert JSF <t:dataList> to ASP.NET datagrid, or converting panelGroup to asp:panel, etc...

    Read the article

  • Java Conversion of byte[] into a srting and then back to a byte[]

    - by Sid
    I am working on a proxy server. I am getting data in byte[] which i convert into a string to perform certain operations. Now when i convert this new string back into a byte [] it causes unkonw problems. So mainly its like i need to know how to correctly convert a byte[] into a string and then back into a byte[] again. I tried to just convert the byte[] to string and then back to byte[] again (to make sure thats its not my operations that are causing problems). So its like: // where reply is a byte[] String str= new String(reply,0, bytesRead); streamToClient.write(str.getBytes(), 0, bytesRead); is not equivalent to streamToClient.write(reply, 0, bytesRead); my proxy works fine when i just send the byte[] without any conversion but when i convert it from byte[] to a string and then back to a byte[] its causes problems. can some one please help? =]

    Read the article

  • Conversion of DOM element selection code to jQuery

    - by Tom McDonnell
    I have a large Javascript codebase to convert to jQuery. The code is structured such that DOM elements are created in Javascript (using a library called DomBuilder), and saved to variables if they will be needed later, before being added to the DOM. Eg. var inputs = { submitConfirm: INPUT({type: 'button', value: 'Submit'}), submitCancel : INPUT({type: 'button', value: 'Cancel'}) }; document.appendChild(inputs.submitConfirm); Then later for example... inputs.submitCancel.style.display = 'none'; inputs.submitCancel.addEventListener('click', onClickSubmitCancel, false); My problem is that jQuery seems to lack a way of manipulating DOM elements directly, as opposed to selecting them first (with for example $('#submitCancel'). Can anyone suggest a way to directly translate the last two Javascript lines given above to use jQuery, given that the DOM elements are already available, and so do not need to be selected?

    Read the article

  • java decmail string to AS 3.0 conversion procedure

    - by Jack Smith
    Hello, I have a problem with conversion java code to action script 3. Anyone can help with code translation? Thanks. public static short[] decmail_str_to_binary_data(String s) { short[] data = new short[s.length()/2]; for (int i = 0; i < s.length(); i += 2) { char c1 = s.charAt(i); char c2 = s.charAt(i + 1); int comb = Character.digit(c1, 16) & 0xff; comb <<= 4; comb += Character.digit(c2, 16) & 0xff; data[i/2] = (short)comb; } return data; }

    Read the article

  • Unusual conversion error (string to integer) asp.net

    - by Phil
    I have my repeater item template: <ItemTemplate> <tr><td><%#Container.DataItem("Category")%></td></tr> </ItemTemplate> Hooked up to: s = "SQL that works ok on server" x = New SqlCommand(s, c) x.Parameters.Add("@contentid", SqlDbType.Int) x.Parameters("@contentid").Value = contentid c.Open() r = x.ExecuteReader If r.HasRows Then Linksrepeater.DataSource = r Linksrepeater.DataBind() End If c.Close() r.Close() When I run the code I get: Invalid Cast Exception was not handled by user code (Conversion from string "category" to type 'Integer' is not valid.) I'm not sure how / why it is trying to convert "Category" to integer as in the db it is a string. Can you please tell me how to avoid this error? thanks.

    Read the article

  • Event receiver on Content Type not triggered on WikiPageLibrary

    - by Ciprian Grosu
    Hello all, I created a new content type for a wiki page library. I added this content type to library by code (the interface did not allow this). Next, I added an event receiver to this content type (on ItemAdded and ItemAdding). My problem is that no event is trrigered. If I add this events directly to the wiki page library all works fine. Is there a limitation/bug/trick ? I looked at the content type attached to the library with SharePoint Manager and in his schema the part for event receiver is missing...I know that there should be something like: <XmlDocuments> <XmlDocument NamespaceURI="http://schemas.microsoft.com/sharepoint/events"> <spe:Receivers xmlns:spe="http://schemas.microsoft.com/sharepoint/events"> <Receiver> <Name> </Name> <Type>1</Type> <SequenceNumber>10000</SequenceNumber> <Assembly>RssFeedWP, Version=1.0.0.0, Culture=neutral, PublicKeyToken=f6722cbeba696def</Assembly> <Class>RssFeedWP.ItemEventReceiver</Class> <Data> </Data> <Filter> </Filter> </Receiver> <Receiver> <Name> </Name> <Type>10001</Type> <SequenceNumber>10000</SequenceNumber> <Assembly>RssFeedWP, Version=1.0.0.0, Culture=neutral, PublicKeyToken=f6722cbeba696def</Assembly> <Class>RssFeedWP.ItemEventReceiver</Class> <Data> </Data> <Filter> </Filter> </Receiver> </spe:Receivers> </XmlDocument> If I look with SPM to the content type added to site I see this part into schema. Here is my code: public override void FeatureActivated(SPFeatureReceiverProperties properties) { using (SPWeb web = (SPWeb)properties.Feature.Parent) { // create RssWiki content type SPContentType rssFeedContentType = new SPContentType(web.AvailableContentTypes["Wiki Page"], web.ContentTypes, "RssFeed Wiki Page"); // add rssfeed url field to the new content type AddFieldToContentType(web, rssFeedContentType, "RssFeed Url", SPFieldType.Note); // add use xslt check box field to the new content type AddFieldToContentType(web, rssFeedContentType, "Use Xslt", SPFieldType.Boolean); // add xslt url field to the new content type AddFieldToContentType(web, rssFeedContentType, "Xslt Url", SPFieldType.Note); web.ContentTypes.Add(rssFeedContentType); rssFeedContentType.Update(); web.Update(); AddContentTypeToList(web, rssFeedContentType); AddEventReceiversToCT(rssFeedContentType); //AddEventReceiverToList(web); } } private void AddFieldToContentType(SPWeb web, SPContentType ct, string fieldName, SPFieldType fieldType) { SPField rssUrlField = null; try { rssUrlField = web.Fields.GetField(fieldName); } catch (Exception ex) { if (rssUrlField == null) { web.Fields.Add(fieldName, fieldType, false); } } SPFieldLink rssUrlFieldLink = new SPFieldLink(web.Fields[fieldName]); ct.FieldLinks.Add(rssUrlFieldLink); } private static void AddContentTypeToList(SPWeb web, SPContentType ct) { SPList wikiList = web.Lists[listName]; wikiList.ContentTypesEnabled = true; wikiList.ContentTypes.Add(ct); wikiList.Update(); } private static void AddEventReceiversToCT(SPContentType ct) { //add event receivers string assemblyName = System.Reflection.Assembly.GetExecutingAssembly().FullName; string ctReceiverName = "RssFeedWP.ItemEventReceiver"; ct.EventReceivers.Add(SPEventReceiverType.ItemAdding, assemblyName, ctReceiverName); ct.EventReceivers.Add(SPEventReceiverType.ItemAdded, assemblyName, ctReceiverName); ct.Update(); } Thx !

    Read the article

  • [Haskell] Problem when mixing type classes and type families

    - by Giuseppe Maggiore
    Hi! This code compiles fine: {-# LANGUAGE MultiParamTypeClasses, FunctionalDependencies, FlexibleInstances, UndecidableInstances, FlexibleContexts, EmptyDataDecls, ScopedTypeVariables, TypeOperators, TypeSynonymInstances, TypeFamilies #-} class Sel a s b where type Res a s b :: * instance Sel a s b where type Res a s b = (s -> (b,s)) instance Sel a s (b->(c,a)) where type Res a s (b->(c,a)) = (b -> s -> (c,s)) but as soon as I add the R predicate ghc fails: {-# LANGUAGE MultiParamTypeClasses, FunctionalDependencies, FlexibleInstances, UndecidableInstances, FlexibleContexts, EmptyDataDecls, ScopedTypeVariables, TypeOperators, TypeSynonymInstances, TypeFamilies #-} class Sel a s b where type Res a s b :: * instance Sel a s b where type Res a s b = (s -> (b,s)) class R a where type Rec a :: * cons :: a -> Rec a elim :: Rec a -> a instance Sel a s (b->(c,Rec a)) where type Res a s (b->(c,Rec a)) = (b -> s -> (c,s)) complaining that: Illegal type synonym family application in instance: b -> (c, Rec a) In the instance declaration for `Sel a s (b -> (c, Rec a))' what does it mean and (most importantly) how do I fix it? Thanks

    Read the article

  • How to deal with multiple sub-type of one super-type in Django admin

    - by Henri
    What would be the best solution for adding/editing multiple sub-types. E.g a super-type class Contact with sub-type class Client and sub-type class Supplier. The way shown here works, but when you edit a Contact you get both inlines i.e. sub-type Client AND sub-type Supplier. So even if you only want to add a Client you also get the fields for Supplier of vice versa. If you add a third sub-type , you get three sub-type field groups, while you actually only want one sub-type group, in the mentioned example: Client. E.g.: class Contact(models.Model): contact_name = models.CharField(max_length=128) class Client(models.Model): contact = models.OneToOneField(Contact, primary_key=True) user_name = models.CharField(max_length=128) class Supplier(models.Model): contact.OneToOneField(Contact, primary_key=True) company_name = models.CharField(max_length=128) and in admin.py class ClientInline(admin.StackedInline): model = Client class SupplierInline(admin.StackedInline): model = Supplier class ContactAdmin(admin.ModelAdmin): inlines = (ClientInline, SupplierInline,) class ClientAdmin(admin.ModelAdmin): ... class SupplierAdmin(admin.ModelAdmin): ... Now when I want to add a Client, i.e. only a Client I edit Contact and I get the inlines for both Client and Supplier. And of course the same for Supplier. Is there a way to avoid this? When I want to add/edit a Client that I only see the Inline for Client and when I want to add/edit a Supplier that I only see the Inline for Supplier, when adding/editing a Contact? Or perhaps there is a different approach. Any help or suggestion will be greatly appreciated.

    Read the article

  • .NET C# : Image Conversion from Bitmap to Icon doesn't seem to work

    - by contactmatt
    I have a simple function that takes a bitmap, and converts the bitmap to an ICON format. Below is the function. (I placed literal values in place of the variables) Bitmap tempBmp = new Bitmap(@"C:\temp\mypicture.jpeg"); Bitmap bmp = new Bitmap(tempBmp, 16, 16); bmp.Save("@C:\temp\mypicture2.ico", ImageFormat.Icon) It doesn't seem to be converting correctly...or so I think. After the image is converted, some browsers do not reconigze the image as a true "ICON" , and even Visual Studio 2008 doesn't reconigze the image as an icon after its converted to an Icon format. For example, I was going to set the Icon property for my Win32 form app with the Icon i just converted. I open the dialouge box and select the icon I just converted and get the following error. -- "Argument 'picture' must be a picture that can be used as a Icon." I've browsed the web and come across complicated code where people take the time to manually convert the bitmap to different formats, but I would think the above code should work, and that the .NET framework would take care of this conversion.

    Read the article

< Previous Page | 1 2 3 4 5 6 7 8 9 10 11 12  | Next Page >