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  • Error with MySQL Query

    - by Ken
    Okay, I must be an idiot, because this is my 3rd question for today. Here's my code: date_default_timezone_set("America/Los_Angeles"); include("mainmenu.php"); $con = mysql_connect("localhost", "root", "********"); if(!$con){ die(mysql_error()); } $usrname = $_POST['usrname']; $fname = $_POST['fname']; $lname = $_POST['lname']; $password = $_POST['password']; $email = $_POST['email']; mysql_select_db("`users`, $con) or die(mysql_error()"); $query = ("INSERT INTO `users`.`data` (`id`, `usrname`, `fname`, `lname`, `email`, `password`) VALUES (NULL, '$usrname', '$fname', '$lname', '$email', 'password'))"); mysql_query('$query') or die(mysql_error()); mysql_close($con); echo("Thank you for registering!"); I always get the error returned as: "You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '$query' at line 1. Help a newbie. I'm about to stab my monitor.

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  • SASS mixin for swapping images / floats on site language (change)

    - by DBUK
    Currently using SASS on a website build. It is my first project using it, tried a little LESS before and liked it. I made a few basic mixins and variables with LESS, super useful stuff! I am trying to get my head around SASS mixins, and syntax, specifically for swapping images when the page changes to a different language, be that with body ID changing or <html lang="en">. And, swapping floats around if, for example, a website changed to chinese. So a mixin where float left is float left unless language is AR and then it becomes float right. With LESS I think it would be something like: .headerBg() when (@lang = en) {background-image:url(../img/hello.png);} .headerBg() when (@lang = it) {background-image:url(../img/ciao.png);} .header {.headerBg(); width: 200px; height:100px} .floatleft() when (@lang = en) { float: left;} .floatleft() when (@lang = ar) { float: right;} .logo {.floatleft();} Its the syntax I am having problems with combined with a brain melting day.

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  • Powershell: splatting after passing hashtable by reference

    - by user1815871
    Powershell newbie ... I recently learned about splatting — very useful. I ran into a snag when I passed a hash table by reference to a function for splatting purposes. (For brevity's sake — a silly example.) Function AllMyChildren { param ( [ref]$ReferenceToHash } get-childitem @ReferenceToHash.Value # etc.etc. } $MyHash = @{ 'path' = '*' 'include' = '*.ps1' 'name' = $null } AllMyChildren ([ref]$MyHash) Result: an error ("Splatted variables cannot be used as part of a property or array expression. Assign the result of the expression to a temporary variable then splat the temporary variable instead."). Tried this afterward: $newVariable = $ReferenceToHash.Value get-childitem @NewVariable That did work and seemed right per the error message. But: is it the preferred syntax in a case like this? (An oh, look, it actually worked solution isn't always a best practice. My approach here strikes me as "Perl-minded" and perhaps in Powershell passing by value is better, though I don't yet know the syntax for it w.r.t. a hash table.)

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  • scheme basic loop

    - by utku
    I'm trying to write a scheme func that behaves in a way similar to a loop. (loop min max func) This loop should perform the func between the range min and max (integers) -- one of an example like this (loop 3 6 (lambda (x) (display (* x x)) (newline))) 9 16 25 36 and I define the function as ( define ( loop min max fn) (cond ((>= max min) ( ( fn min ) ( loop (+ min 1 ) max fn) ) ) ) ) when I run the code I get the result then an error occur. I couldn't handle this error. (loop 3 6 (lambda (x) (display(* x x))(newline))) 9 16 25 36 Backtrace: In standard input: 41: 0* [loop 3 6 #] In utku1.scheme: 9: 1 (cond ((= max min) ((fn min) (loop # max fn)))) 10: 2 [# ... 10: 3* [loop 4 6 #] 9: 4 (cond ((= max min) ((fn min) (loop # max fn)))) 10: 5 [# ... 10: 6* [loop 5 6 #] 9: 7 (cond ((= max min) ((fn min) (loop # max fn)))) 10: 8 [# ... 10: 9* [loop 6 6 #] 9: 10 (cond ((= max min) ((fn min) (loop # max fn)))) 10: 11 [# #] utku1.scheme:10:31: In expression ((fn min) (loop # max ...)): utku1.scheme:10:31: Wrong type to apply: #<unspecified> ABORT: (misc-error)

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  • MySQL nested CASE error I need help with?

    - by AK
    What I am trying to do here is: IF the records in table todo as identified in $done have a value in the column recurinterval then THEN reset date_scheduled column ELSE just set status_id column to 6 for those records. This is the error I get from mysql_error() ... You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'CASE recurinterval != 0 AND recurinterval IS NOT NULL THEN SET date_sche' at line 2 How can I make this statement work? UPDATE todo CASE recurinterval != 0 AND recurinterval IS NOT NULL THEN SET date_scheduled = CASE recurunit WHEN 'DAY' THEN DATE_ADD(date_scheduled, INTERVAL recurinterval DAY) WHEN 'WEEK' THEN DATE_ADD(date_scheduled, INTERVAL recurinterval WEEK) WHEN 'MONTH' THEN DATE_ADD(date_scheduled, INTERVAL recurinterval MONTH) WHEN 'YEAR' THEN DATE_ADD(date_scheduled, INTERVAL recurinterval YEAR) END WHERE todo_id IN ($done) ELSE SET status_id = 6 WHERE todo_id IN ($done) END The following mySQL statement worked just fine before I revised like above. UPDATE todo SET date_scheduled = CASE recurunit WHEN 'DAY' THEN DATE_ADD(date_scheduled, INTERVAL recurinterval DAY) WHEN 'WEEK' THEN DATE_ADD(date_scheduled, INTERVAL recurinterval WEEK) WHEN 'MONTH' THEN DATE_ADD(date_scheduled, INTERVAL recurinterval MONTH) WHEN 'YEAR' THEN DATE_ADD(date_scheduled, INTERVAL recurinterval YEAR) END WHERE todo_id IN ($done) AND recurinterval != 0 AND recurinterval IS NOT NULL

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  • Char C question about encoding signed/unsigned.

    - by drigoSkalWalker
    Hi guys. I read that C not define if a char is signed or unsigned, and in GCC page this says that it can be signed on x86 and unsigned in PowerPPC and ARM. Okey, I'm writing a program with GLIB that define char as gchar (not more than it, only a way for standardization). My question is, what about UTF-8? It use more than an block of memory? Say that I have a variable unsigned char *string = "My string with UTF8 enconding ~ çã"; See, if I declare my variable as unsigned I will have only 127 values (so my program will to store more blocks of mem) or the UTF-8 change to negative too? Sorry if I can't explain it correctly, but I think that i is a bit complex. NOTE: Thanks for all answer I don't understand how it is interpreted normally. I think that like ascii, if I have a signed and unsigned char on my program, the strings have diferently values, and it leads to confuse, imagine it in utf8 so.

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  • typedef struct, circular dependency, forward definitions

    - by BlueChip
    The problem I have is a circular dependency issue in C header files ...Having looked around I suspect the solution will have something to do with Forward Definitions, but although there are many similar problems listed, none seem to offer the information I require to resolve this one... I have the following 5 source files: // fwd1.h #ifndef __FWD1_H #define __FWD1_H #include "fwd2.h" typedef struct Fwd1 { Fwd2 *f; } Fwd1; void fwd1 (Fwd1 *f1, Fwd2 *f2) ; #endif // __FWD1_H . // fwd1.c #include "fwd1.h" #include "fwd2.h" void fwd1 (Fwd1 *f1, Fwd2 *f2) { return; } . // fwd2.h #ifndef __FWD2_H #define __FWD2_H #include "fwd1.h" typedef struct Fwd2 { Fwd1 *f; } Fwd2; void fwd2 (Fwd1 *f1, Fwd2 *f2) ; #endif // __FWD2_H . // fwd2.c #include "fwd1.h" #include "fwd2.h" void fwd2 (Fwd1 *f1, Fwd2 *f2) { return; } . // fwdMain.c #include "fwd1.h" #include "fwd2.h" int main (int argc, char** argv, char** env) { Fwd1 *f1 = (Fwd1*)0; Fwd2 *f2 = (Fwd2*)0; fwd1(f1, f2); fwd2(f1, f2); return 0; } Which I am compiling with the command: gcc fwdMain.c fwd1.c fwd2.c -o fwd -Wall I have tried several ideas to resolve the compile errors, but have only managed to replace the errors with other errors ...How do I resolve the circular dependency issue with the least changes to my code? ...Ideally, as a matter of coding style, I would like to avoid putting the word "struct" all over my code.

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  • Migrate Data and Schema from MySQL to SQL Server

    - by colithium
    Are there any free solutions for automatically migrating a database from MySQL to SQL Server Server that "just works"? I've been attempting this simple (at least I thought so) task all day now. I've tried: SQL Server Management Studio's Import Data feature Create an empty database Tasks - Import Data... .NET Framework Data Provider for Odbc Valid DSN (verified it connects) Copy data from one or more tables or views Check 1 VERY simple table Click Preview Get Error: The preview data could not be retrieved. ADDITIONAL INFORMATION: ERROR [42000] [MySQL][ODBC 5.1 Driver][mysqld-5.1.45-community]You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '"table_name"' at line 1 (myodbc5.dll) A similar error occurs if I go through the rest of the wizard and perform the operation. The failed step is "Setting Source Connection" the error refers to retrieving column information and then lists the above error. It can retrieve column information just fine when I modify column mappings so I really don't know what the issue is. I've also tried getting various MySql tools to output ddl statements that SQL Server understand but haven't succeeded. I've tried with MySQL v5.1.11 to SQL Server 2005 and with MySQL v5.1.45 to SQL Server 2008 (with ODBC drivers 3.51.27.00 and 5.01.06.00 respectively)

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  • LINQ to Entites - Left Outer Join - SQL 2000

    - by user255234
    Hi! I'm using Linq to Entities. I have the following query in my code, it includes left outer Join: var surgeonList = (from item in context.T1_STM_Surgeon.Include("T1_STM_SurgeonTitle") .Include("OTER").Include("OSLP") join reptable in context.OSLP on item.Rep equals reptable.SlpCode into surgRepresentative where item.ID == surgeonId select new { ID = item.ID, First = item.First, Last = item.Last, Rep = (surgRepresentative.FirstOrDefault() != null) ? surgRepresentative.FirstOrDefault().SlpName : "N/A", Reg = item.OTER.descript, PrimClinic = item.T1_STM_ClinicalCenter.Name, Titles = item.T1_STM_SurgeonTitle, Phone = item.Phone, Email = item.Email, Address1 = item.Address1, Address2 = item.Address2, City = item.City, State = item.State, Zip = item.Zip, Comments = item.Comments, Active = item.Active, DateEntered = item.DateEntered }) .ToList(); My DEV server has SQL 2008, so the code works just fine. When I moved this code to client's production server - they use SQL 2000, I started getting "Incorrect syntax near '(' ". I've tried changing the ProviderManifestToken to 2000 in my .edmx file, then I started getting "The execution of this query requires the APPLY operator, which is not supported in versions of SQL Server earlier than SQL Server 2005." I tied changing the token to 2005, the "Incorrect syntax near '(' " is back. Can anybody help me to find a workaround for this? Thank you very much in advance!

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  • using spring, hibernate and scala, is there a better way to load test data than dbunit?

    - by egervari
    Here are some things I really dislike about dbunit: 1) You cannot specify the exact ordering the inserts because dbunit likes to group your inserts by table name, and not by the order you define them in the XML file. This is a problem when you have records depending on other records in other tables, so you have to disable foreign key constraints during your tests... which actually sucks because these foreign key constraints will get fired in production while your tests won't be aware of them! 2) They seem hellbent on forcing you to use an xml namespace to define your xml... and I honestly can't be bothered to do this. I like the data.xml without any namespace. It works. But they are so hellbent on deprecating it. 3) Creating different xml files is hard on a per test basis, so it actually encourages creating data for your entire app. Unfortunately, this process is a little bloated too once the data grows in size and things get inter tangled. There has got to be a better way to split up your test data into chunks without having to copy/paste a lot of the test data across all of your tests. 4) Keeping track of id references in a big xml file is just impossible. If you have 130 domain classes, it just gets bewildering. This model simply does not scale. Is there something less bloated and better in the Spring/Hibernate space? db unit has worn out its welcome and I'm really looking for something better.

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  • Matching innermost braces with regex or strpos?

    - by rich97
    I have a sort of mini parsing syntax I made up to help me streamline my view code in cakephp. Basically I have created a table helper which, when given a dataset and (optionally) a set of options for how to format the data will render out a table, as opposed to me looping though the data and editing it manually. It allows the user to be as complex or as simple as they like, it can get pretty powerful. However, In order to achieve this I had to make a simple parsing syntax. As a quick example the user would do something like so: $this->Table->data = $userData; $this->Table->elements['td']['data'] = array( '{:User.username:}', '{:User.created:}' => array('Time::nice') ); echo $this->Table->render(); And when rendering the table would then generate: <table> <tbody> <tr><td>rich97</td><td>Sun 21st 02:30pm</td></tr> </tbody> </table> The problem occurs then I try to nest the braces like so: {:User.levels.iconClasses.{:User.access:}:} Is there anyway I can only get the inner most brackets on the first time round and loop though until there are no matches? Or even do it in one go? Or even better use strpos? Here is my regex as it stands: '/\{\:([^}]+)\:\}/'

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  • How do I use the Enum value from a class in another part of code?

    - by ChiggenWingz
    Coming from a C# background from a night course at a local college, I've sort of started my way in C++. Having a lot pain getting use to the syntax. I'm also still very green when it comes to coding techniques. From my WinMain function, I want to be able to access a variable which is using an enum I declared in another class. (inside core.h) class Core { public: enum GAME_MODE { INIT, MENUS, GAMEPLAY }; GAME_MODE gameMode; Core(); ~Core(); ...OtherFunctions(); }; (inside main.cpp) Core core; int WINAPI WinMain(...) { ... startup code here... core.gameMode = Core.GAME_MODE.INIT; ...etc... } Basically I want to set that gameMode to the enum value of Init or something like that from my WinMain function. I want to also be able to read it from other areas. I get the error... expected primary-expression before '.' token If I try to use core.gameMode = Core::GAME_MODE.INIT;, then I get the same error. I'm not fussed about best practices, as I'm just trying to get the basic understanding of passing around variables in C++ between files. I'll be making sure variables are protected and neatly tucked away later on once I am use to the flexibility of the syntax. If I remember correctly, C# allowed me to use Enums from other classes, and all I had to do was something like Core.ENUMNAME.ENUMVALUE. I hope what I'm wanting to do is clear :\ As I have no idea what a lot of the correct terminology is.

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  • why malloc+memset slower than calloc?

    - by kingkai
    It's known that calloc differentiates itself with malloc in which it initializes the memory alloted. With calloc, the memory is set to zero. With malloc, the memory is not cleared. So in everyday work, i regard calloc as malloc+memset. Incidentally, for fun, i wrote the following codes for benchmark. The result is confused. Code 1: #include<stdio.h> #include<stdlib.h> #define BLOCK_SIZE 1024*1024*256 int main() { int i=0; char *buf[10]; while(i<10) { buf[i] = (char*)calloc(1,BLOCK_SIZE); i++; } } time ./a.out real 0m0.287s user 0m0.095s sys 0m0.192s Code 2: #include<stdio.h> #include<stdlib.h> #include<string.h> #define BLOCK_SIZE 1024*1024*256 int main() { int i=0; char *buf[10]; while(i<10) { buf[i] = (char*)malloc(BLOCK_SIZE); memset(buf[i],'\0',BLOCK_SIZE); i++; } } time ./a.out real 0m2.693s user 0m0.973s sys 0m1.721s Repalce memset with bzero(buf[i],BLOCK_SIZE) in Code 2 produce the result alike. My Question is that why malloc+memset is so much slower than calloc? How can calloc do that ? Thanks!

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  • Does new JUnit 4.8 @Category render test suites almost obsolete?

    - by grigory
    Given question 'How to run all tests belonging to a certain Category?' and the answer would the following approach be better for test organization? define master test suite that contains all tests (e.g. using ClasspathSuite) design sufficient set of JUnit categories (sufficient means that every desirable collection of sets is identifiable using one or more categories) define targeted test suites based on master test suite and set of categories For example: identify categories for speed (slow, fast), dependencies (mock, database, integration), function (), domain ( demand that each test is properly qualified (tagged) with relevant set of categories. create master test suite using ClasspathSuite (all tests found in classpath) create targeted suites by qualifying master test suite with categories, e.g. mock test suite, fast database test suite, slow integration for domain X test suite, etc. My question is more like soliciting approval rate for such approach vs. classic test suite approach. One unbeatable benefit is that every new test is immediately contained by relevant suites with no suite maintenance. One concern is proper categorization of each test.

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  • Why I'm not getting "Multiple definition" error from the g++?

    - by ban
    I tried to link my executable program with 2 static libraries using g++. The 2 static libraries have the same function name. I'm expecting a "multiple definition" linking error from the linker, but I did not received. Can anyone help to explain why is this so? staticLibA.h #ifndef _STATIC_LIBA_HEADER #define _STATIC_LIBA_HEADER int hello(void); #endif staticLibA.cpp #include "staticLibA.h" int hello(void) { printf("\nI'm in staticLibA\n"); return 0; } output: g++ -c -Wall -fPIC -m32 -o staticLibA.o staticLibA.cpp ar -cvq ../libstaticLibA.a staticLibA.o a - staticLibA.o staticLibB.h #ifndef _STATIC_LIBB_HEADER #define _STATIC_LIBB_HEADER int hello(void); #endif staticLibB.cpp #include "staticLibB.h" int hello(void) { printf("\nI'm in staticLibB\n"); return 0; } output: g++ -c -Wall -fPIC -m32 -o staticLibB.o staticLibB.cpp ar -cvq ../libstaticLibB.a staticLibB.o a - staticLibB.o main.cpp extern int hello(void); int main(void) { hello(); return 0; } output: g++ -c -o main.o main.cpp g++ -o multipleLibsTest main.o -L. -lstaticLibA -lstaticLibB -lstaticLibC -ldl -lpthread -lrt

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  • emacs: How to intelligently handle buffer-modified when setting text properties?

    - by Cheeso
    The documentation on Text Properties says: Since text properties are considered part of the contents of the buffer (or string), and can affect how a buffer looks on the screen, any change in buffer text properties marks the buffer as modified. First, I don't understand that policy. Can anyone explain? The text props are not actually saved in the file, when the buffer is saved. So why mark the buffer as modified? For me, buffer-modified indicates "some changes have not yet been saved." but understanding the policy is just for my own amusement. More importantly, is there an already-established way that, in code, I can change syntax text properties on the text in a buffer, while keeping the buffer-modified flag set to whatever it was, prior to those changes? I'm thinking of something like save-excursion. It would be pretty easy to write, but this seems like a common case and I'd like to use the standard function, if possible. For more on the scenario - I have a mode that does a full text scan and sets syntax-tabe properties on the text. After opening a buffer, the scan runs, but it results in a buffer with buffer-modified set to t . As always, thanks.

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  • Invalid Argument javascript error only on certain computers

    - by Jen
    Getting an error whenever we click a particular button/link on our site. It is generating a javascript "Invalid Argument" error. I know in the other posts it is typically because it is a syntax error in the javascript however it only just seems to have started happening and it doesn't happen on all pcs. ie. in our client's environment if I remote onto their web server and view the uat website I get the javascript error. If I remote onto their sql server and view the uat website I don't get the javascript error. If it was a syntax error then I would always get the error wouldn't I? both browsers are the same version of IE6 (yeah I know...) :) I have tried deleting temporary internet files - including viewing the files and deleting them myself - but no joy. client uses citrix.. and they're all getting the error :( Any ideas would be appreciated - Thanks! :) Update - Sorry I haven't posted specific code as there is too much to post (and I'm not sure where the error is occurring). The "button" launches a new window which in turn opens up a couple of aspx pages and calls lots of javascript. So the window opens ok, and there's a function that gets called to resize the window - but before it calls the resizing of the window/content it throws the invalid argument error. Am busy trying to get alerts to trigger to see if I can see where it's falling over but so far no luck. Again not sure why this error doesn't occur when I use a particular PC (same browser version)

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  • How to write an R function that evaluates an expression within a data-frame

    - by Prasad Chalasani
    Puzzle for the R cognoscenti: Say we have a data-frame: df <- data.frame( a = 1:5, b = 1:5 ) I know we can do things like with(df, a) to get a vector of results. But how do I write a function that takes an expression (such as a or a > 3) and does the same thing inside. I.e. I want to write a function fn that takes a data-frame and an expression as arguments and returns the result of evaluating the expression "within" the data-frame as an environment. Never mind that this sounds contrived (I could just use with as above), but this is just a simplified version of a more complex function I am writing. I tried several variants ( using eval, with, envir, substitute, local, etc) but none of them work. For example if I define fn like so: fn <- function(dat, expr) { eval(expr, envir = dat) } I get this error: > fn( df, a ) Error in eval(expr, envir = dat) : object 'a' not found Clearly I am missing something subtle about environments and evaluation. Is there a way to define such a function?

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  • Is there a way to find out whether a class is a direct base of another class?

    - by user176168
    Hi I'm wondering whether there is a way to find out whether a class is a direct base of another class i.e. in boost type trait terms a is_direct_base_of function. As far as I can see boost doesn't see to support this kind of functionality which leads me to think that its impossible with the current C++ standard. The reason I want it is to do some validation checking on two macro's that are used for a reflection system to specify that one class is derived from another e.g. header.h: #define BASE A #define DERIVED B class A {}; class B : public A { #include <rtti.h> }; rtti.h: // I want to check that the two macro's are correct with a compile time assert Rtti<BASE, DERIVED> m_rtti; Although the macro's seem unnecessary in this simple example in my real world scenario rtti.h is a lot more complex. One possible avenue would be to compare the size of the this pointer with the size of a this pointer cast to the base type and some how trying to figure out whether its the size of the base class itself away or something (yeah your right I don't know how that would work either! lol)

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  • Structure map and generics (in XML config)

    - by James D
    Hi I'm using the latest StructureMap (2.5.4.264), and I need to define some instances in the xml configuration for StructureMap using generics. However I get the following 103 error: Unhandled Exception: StructureMap.Exceptions.StructureMapConfigurationException: StructureMap configuration failures: Error: 103 Source: Requested PluginType MyTest.ITest`1[[MyTest.Test,MyTest]] configured in Xml cannot be found Could not create a Type for 'MyTest.ITest`1[[MyTest.Test,MyTest]]' System.ApplicationException: Could not create a Type for 'MyTest.ITest`1[[MyTest.Test,MyTest]]' ---> System.TypeLoadException: Could not loa d type 'MyTest.ITest`1' from assembly 'StructureMap, Version=2.5.4.264, Culture=neutral, PublicKeyToken=e60ad81abae3c223'. at System.RuntimeTypeHandle._GetTypeByName(String name, Boolean throwOnError, Boolean ignoreCase, Boolean reflectionOnly, StackCrawlMark& stackMark, Boolean loadTypeFromPartialName) at System.RuntimeTypeHandle.GetTypeByName(String name, Boolean throwOnError, Boolean ignoreCase, Boolean reflectionOnly, StackCrawlMark& stackMark) at System.RuntimeType.PrivateGetType(String typeName, Boolean throwOnError, Boolean ignoreCase, Boolean reflectionOnly, StackCrawlMark& s tackMark) at System.Type.GetType(String typeName, Boolean throwOnError) at StructureMap.Graph.TypePath.FindType() --- End of inner exception stack trace --- at StructureMap.Graph.TypePath.FindType() at StructureMap.Configuration.GraphBuilder.ConfigureFamily(TypePath pluginTypePath, Action`1 action) A simply replication of the code is as follows: public interface ITest<T> { } public class Test { } public class Concrete : ITest<Test> { } Which I then wish to define in the XML configuration something as follows: <DefaultInstance PluginType="MyTest.ITest`1[[MyTest.Test,MyTest]],MyTest" PluggedType="MyTest.Concrete,MyTest" Scope="Singleton" /> I've been racking my brain, however I can't see what I'm doing wrong - I've used Type.GetType to verify the type actually is valid which it is. Anyone have any ideas? Thanks !

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  • OOP design issue: Polymorphism

    - by Graham Phillips
    I'm trying to solve a design issue using inheritance based polymorphism and dynamic binding. I have an abstract superclass and two subclasses. The superclass contains common behaviour. SubClassA and SubClassB define some different methods: SubClassA defines a method performTransform(), but SubClassB does not. So the following example 1 var v:SuperClass; 2 var b:SubClassB = new SubClassB(); 3 v = b; 4 v.performTransform(); would cause a compile error on line 4 as performTransform() is not defined in the superclass. We can get it to compile by casting... (v as SubClassA).performTransform(); however, this will cause a runtime exception to be thrown as v is actually an instance of SubClassB, which also does not define performTransform() So we can get around that by testing the type of an object before casting it: if( typeof v == SubClassA) { (cast v to SubClassA).performTransform(); } That will ensure that we only call performTransform() on v's that are instances of SubClassA. That's a pretty inelegant solution to my eyes, but at least its safe. I have used interface based polymorphism (interface meaning a type that can't be instantiated and defines the API of classes that implement it) in the past, but that also feels clunky. For the above case, if SubClassA and SubClassB implemented ISuperClass that defined performTransform, then they would both have to implement performTransform(). If SubClassB had no real need for a performTransform() you would have to implement an empty function. There must be a design pattern out there that addresses the issue.

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  • How to Create the Upload File for Application Loader?

    - by Ohad Regev
    When I use Application Loader, I get to the point where it asks me to "Choose..." the file to be uploaded. If I understand correctly, it supposes to be the appName.app file I see under "Products" on my app bundle (I right click it and select "Show in Finder" to get to the specific file in library; then I'm supposed to ZIP it and the ZIP file is what I will choose in Application Loader). First, am I correct with this assumption? if yes... What should I define different in XCode than the way I used to build the application for testing (on simulator and on my personal iPhone)? Should I change the Info---Command-line build use from Debug to Release? How should I define the Build Settings---Code Signing section (in which field should I select the "iPhone Developer" option and in which should it be "iPhone Distribution")? Are there any other important Info/Build Settings/p.list/etc... fields I should relate to? any help will be appreciated...

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  • How can I abstract out the core functionality of several Rails applications?

    - by hornairs
    I'd like to develop a number of non-trivial Rails applications which all implement a core set of functionality but each have certain particular customizations, extensions, and aesthetic differences. How can I pull the core functionality (models, controllers, helpers, support classes, tests) common to all these systems out in such a way that updating the core will benefit every application based upon it? I've seen Rails Engines but they seem to be too detached, almost too abstracted to be built upon. I can seem them being useful for adding one component to an existing app, for example bolting on a blog engine to your existing e-commerce site. Since engines seem to be mostly self contained, it seems difficult and inconvenient to override their functionality and views while keeping DRY. I've also considered abstracting the code into a gem, but this seems a little odd. Do I make the gem depend on the Rails gems, and the define models & controllers inside it, and then subclass them in my various applications? Or do I define many modules inside the gem that I include in the different spots inside my various applications? How do I test the gem and then test the set of customizations and overridden functionality on top of it? I'm also concerned with how I'll develop the gem and the Rails apps in tandem, can I vendor a git repository of the gem into the app and push from that so I don't have to build a new gem every iteration? Also, are there private gem hosts/can I set my own gem source up? Also, any general suggestions for this kind of undertaking? Abstraction paradigms to adhere to? Required reading? Comments from the wise who have done this before? Thanks!

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  • LINQ extention SelectMany in 3.5 vs 4.0?

    - by Moberg
    Hi When I saw Darins suggestion here .. IEnumerable<Process> processes = new[] { "process1", "process2" } .SelectMany(Process.GetProcessesByName); ( http://stackoverflow.com/questions/3059667/process-getprocessesbyname/3059733#3059733 ) .. I was a bit intrigued and I tried it in VS2008 with .NET 3.5 - and it did not compiling unless I changed it to .. IEnumerable<Process> res = new string[] { "notepad", "firefox", "outlook" } .SelectMany(s => Process.GetProcessesByName(s)); Having read some Darins answers before I suspected that it was me that were the problem, and when I later got my hands on a VS2010 with.NET 4.0 - as expected - the original suggestion worked beautifully. My question is : What have happend from 3.5 to 4.0 that makes this (new syntax) possible? Is it the extentionmethods that have been extended(hmm) or new rules for lambda syntax or? I've tried to search but my google-fu was not strong enough. Please forgive if the question is a bit naive and note that I've taged it as beginner :)

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  • Sencha 2 : Sync models with hasMany associations in LocalStorage

    - by Alytrem
    After hours and hours trying to do this, I need your help. I have to models : Project and Task. A project hasMany tasks and a task belong to a project. Everyting works well if you don't use a store to save these models. I want to save both tasks and projects in two stores (TaskStore and ProjectStore). These stores use a LocalStorage proxy. I tried many things, and the most logical is : Ext.define('MyApp.model.Task', { extend: 'Ext.data.Model', config: { fields: [ { name: 'name', type: 'string' }, { dateFormat: 'd/m/Y g:i', name: 'start', type: 'date' }, { dateFormat: 'd/m/Y g:i', name: 'end', type: 'date' }, { name: 'status', type: 'string' } ], belongsTo: { model: 'MyApp.model.Project' } } }); Ext.define('MyApp.model.Project', { extend: 'Ext.data.Model', alias: 'model.Project', config: { hasMany: { associationKey: 'tasks', model: 'MyApp.model.Task', autoLoad: true, foreignKey: 'project_id', name: 'tasks', store: {storeId: "TaskStore"} }, fields: [ { name: 'name', type: 'string' }, { dateFormat: 'd/m/Y', name: 'start', type: 'date' }, { dateFormat: 'd/m/Y', name: 'end', type: 'date' } ] } }); This is my "main" : var project = Ext.create("MyApp.model.Project", {name: "mojo", start: "17/03/2011", end: "17/03/2012", status: "termine"}); var task = Ext.create("MyApp.model.Task", {name: "todo", start: "17/03/2011 10:00", end: "17/03/2012 19:00", status: "termine"}); project.tasks().add(task); Ext.getStore("ProjectStore").add(project); The project is added to the store, but task is not. Why ?!

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