Search Results

Search found 4771 results on 191 pages for 'aspnet compiler'.

Page 157/191 | < Previous Page | 153 154 155 156 157 158 159 160 161 162 163 164 | Next Page >

In .NET, Why Can I Access Private Members of a Class Instance within the Class?

- by AMissico

While cleaning some code today written by someone else, I changed the access modifier from Public to Private on a class variable/member/field. I expected a long list of compiler errors that I use to "refactor/rework/review" the code that used this variable. Imagine my surprise when I didn't get any errors. After reviewing, it turns out that another instance of the Class can access the private members of another instance declared within the Class. Totally unexcepted. Is this normal? I been coding in .NET since the beginning and never ran into this issue, nor read about it. I may have stumbled onto it before, but only "vaguely noticed" and move on. Can anyone explain this behavoir to me? I would like to know the "why" I can do this. Please explain, don't just tell me the rule. Am I doing something wrong? I found this behavior in both C# and VB.NET. The code seems to take advantage of the ability to access private variables. Sincerely, Totally Confused Class Jack Private _int As Integer End Class Class Foo Public Property Value() As Integer Get Return _int End Get Set(ByVal value As Integer) _int = value * 2 End Set End Property Private _int As Integer Private _foo As Foo Private _jack As Jack Private _fred As Fred Public Sub SetPrivate() _foo = New Foo _foo.Value = 4 'what you would expect to do because _int is private _foo._int = 3 'TOTALLY UNEXPECTED _jack = New Jack '_jack._int = 3 'expected compile error _fred = New Fred '_fred._int = 3 'expected compile error End Sub Private Class Fred Private _int As Integer End Class End Class

Read the article
Go: using a pointer to array

- by Sean

I'm having a little play with google's Go language, and I've run into something which is fairly basic in C but doesn't seem to be covered in the documentation I've seen so far When I pass a pointer to an array to a function, I presumed we'd have some way to access it as follows: func conv(x []int, xlen int, h []int, hlen int, y *[]int) for i := 0; i<xlen; i++ { for j := 0; j<hlen; j++ { *y[i+j] += x[i]*h[j] } } } But the Go compiler doesn't like this: sean@spray:~/dev$ 8g broke.go broke.go:8: invalid operation: y[i + j] (index of type *[]int) Fair enough - it was just a guess. I have got a fairly straightforward workaround: func conv(x []int, xlen int, h []int, hlen int, y_ *[]int) { y := *y_ for i := 0; i<xlen; i++ { for j := 0; j<hlen; j++ { y[i+j] += x[i]*h[j] } } } But surely there's a better way. The annoying thing is that googling for info on Go isn't very useful as all sorts of C\C++\unrelated results appear for most search terms.

Read the article
Spring Stripes framework problem

- by ali

I am new to stripes and am attempting to integrate spring into stripes In the following code : public class ContactFormActionBeanTest { private static MockServletContext mockServletContext; private static MockHttpSession mockSession; @BeforeClass public static void setup() throws Exception { mockServletContext = new MockServletContext("webmail"); Map<String,String> params = new HashMap<String,String>(); params.put("ActionResolver.Packages", "stripesbook.action"); params.put("Extension.Packages", "stripesbook.ext," + "net.sourceforge.stripes.integration.spring"); mockServletContext.addFilter(StripesFilter.class, "StripesFilter", params); mockServletContext.setServlet(DispatcherServlet.class, "DispatcherServlet", null); mockSession = new MockHttpSession(mockServletContext); mockServletContext.addInitParameter("contextConfigLocation", "/WEB-INF/applicationContext-test.xml"); ContextLoaderListener springContextLoader = new ContextLoaderListener(); springContextLoader.contextInitialized( new ServletContextEvent(mockServletContext)); // Load mock user MockRoundtrip trip = new MockRoundtrip(mockServletContext, MockDataLoaderActionBean.class, mockSession); trip.execute(); // Login mock user trip = new MockRoundtrip(mockServletContext, LoginActionBean.class, mockSession); trip.setParameter("username", "freddy"); trip.setParameter("password", "nadia"); trip.execute("login"); } I get null in springContextLoader ContextLoaderListener springContextLoader = new ContextLoaderListener(); and test fails. Am I missing something? I am using eclipse with maven. Also when I try to deploy it for tomcat 6.0 I get following warnings: WARN net.sourceforge.stripes.util.ResolverUtil - Could not examine class 'stripesbook/ext/ContactFormatter.class' due to a java.lang.UnsupportedClassVersionError with message: Bad version number in .class file (unable to load class stripesbook.ext.ContactFormatter) I have checked to be sure that I am compiling with Java 5(set JDK compiler to 1.5) instead of 1.6 (Java 6); but didn't work out for me and still have problems running spring-stripes integrated project.

Read the article
Passing control references as ref parameters

- by Enmanuel

Hi everyone. Please help me out here because im getting kind of confused.. I have a form in a C# winforms project and a couple of methods that are suposed to perform some tasks for this particular form and all derived ones, so one of those helper methods can make the example.. this one should fill comboboxes with a dataset. Its working properly now but when i coded the method with this signature protected void FillComboBox(kComboBox target, IEntClass_DA entity) { target.DataSource = entity.GetList().Tables[0]; target.DisplayMember = "name"; target.ValueMember = "id"; } I saw that the displayMember and ValueMember in the comboboxes were not holding the values after the method call. I just thought I should use ref parameters so the asignments are not wasted in read-only reference variables. It was ok by then but later, making an exercise of passing the whole form as a parameter I was warned by the compiler with the notice that this could not be passed as a ref parameter because it is read-only. Fine then, I keep working and see that even without the ref keyword i can use the ref variable from the form, update some properties and see the changes. So whats happening here: passing a reference of the control to the helper method gives me ability to change its members even when not using the ref parameter?? Thanks.

Read the article
What is faster- Java or C# (Or good old C)?

- by Rexsung

I'm currently deciding on a platform to build a scientific computational product on, and am deciding on either C#, Java, or plain C with Intels compiler on Core2 Quad CPU's. It's mostly integer arithmetic. My benchmarks so far show Java and C are about on par with each other, and dotNET/C# trails by about 5%- however a number of my coworkers are claiming that dotNET with the right optimizations will beat both of these given enough time for the JIT to do its work. I always assume that the JIT would have done it's job within a few minutes of the app starting (Probably a few seconds in my case, as it's mostly tight loops), so I'm not sure whether to believe them Can anyone shed any light on the situation? Would dotNET beat Java? (Or am I best just sticking with C at this point?). The code is highly multithreaded and data sets are several terabytes in size. Haskell/erlang etc are not options in this case as there is a significant quantity of existing legacy C code that will be ported to the new system, and porting C to Java/C# is a lot simpler than to Haskell or Erlang. (Unless of course these provide a significant speedup). Edit: We are considering moving to C# or Java because they may, in theory, be faster. Every percent we can shave off our processing time saves us tens of thousands of dollars per year. At this point we are just trying to evaluate whether C, Java, or c# would be faster.

Read the article
Can I use a *.tag from another *.tag file in the same /WEB-INF/tags folder?

- by Ytsejammer

Hello, I am trying to refactor my JSP code so that a small conditional test condition gets reused through a *.tag file. There are some big parts of my UI that depend on the value of a two-state property of an object present in the request. Let's say the property is 'gender' and the object is of type Person. Like I said, I would like to simplify & centralize the test on the gender property using a tag. For this purpose, I created two tag files: /WEB-INF/tags/if-male.tag /WEB-INF/tags/if-female.tag Now, I have another tiny spot that gets repeated in all over my application; let's say is the salutation to my site user. With this idea, I created a tag like this: /WEB-INF/tags/salutation.tag As you can imagine, I am trying to use the if-male/if-female test within the salutation.tag file to output 'Mrs.' or 'Mr.' like this: <%@ tag body-content="empty" %> <%@ taglib prefix="g" uri="/WEB-INF/tags" %> <g:if-male> Mr. </g:if-male> <g:if-female> Mrs. </g:if-female> Is the use of the if-male/if-female tags legal within the salutation.tag file? I have tried with such arrangement, but it looks like the JDeveloper 10.1.3.4 compiler gets confused and cannot deal with the salutation.tag tag invoking the other two tags in the same 'library' (folder under /WEB-INF/tags). The reference works perfectly in Jetty 6 and it looks like it works as well if I deploy the application to OC4J directly without relying on JDeveloper to pre-compile all my JSPs. I hope someone can shed some light on this. Thanks, YJ

Read the article
Common practice for higher-order-polymorphism in scala

- by raichoo

Hi, I'm trying to grasp higher-order-polymophism in scala by implementing a very basic interface that describes a monad but I come across a problem that I don't really understand. I implemented the same with C++ and the code looks like this: #include <iostream> template <typename T> class Value { private: T value; public: Value(const T& t) { this->value = t; } T get() { return this->value; } }; template < template <typename> class Container > class Monad { public: template <typename A> Container<A> pure(const A& a); }; template <template <typename> class Container> template <typename A> Container<A> Monad<Container>::pure(const A& a) { return Container<A>(a); } int main() { Monad<Value> m; std::cout << m.pure(1).get() << std::endl; return 0; } When trying to do the same with scala I fail: class Value[T](val value: T) class Monad[Container[T]] { def pure[A](a: A): Container[A] = Container[A](a) } object Main { def main(args: Array[String]): Unit = { val m = new Monad[Value] m.pure(1) } } The compiler complains about: [raichoo@lain:Scala]:434> scalac highorder.scala highorder.scala:5: error: not found: value Container Container[A](a) ^ one error found What am I doing wrong here? There seems to be a fundamental concept I don't seem to understand about scala typeconstructors. Regards, raichoo

Read the article
What Scheme Does Ghuloum Use?

- by Don Wakefield

I'm trying to work my way through Compilers: Backend to Frontend (and Back to Front Again) by Abdulaziz Ghuloum. It seems abbreviated from what one would expect in a full course/seminar, so I'm trying to fill in the pieces myself. For instance, I have tried to use his testing framework in the R5RS flavor of DrScheme, but it doesn't seem to like the macro stuff: src/ghuloum/tests/tests-driver.scm:6:4: read: illegal use of open square bracket I've read his intro paper on the course, An Incremental Approach to Compiler Construction, which gives a great overview of the techniques used, and mentions a couple of Schemes with features one might want to implement for 'extra credit', but he doesn't mention the Scheme he uses in the course. Update I'm still digging into the original question (investigating options such as Petit Scheme suggested by Eli below), but found an interesting link relating to Gholoum's work, so I am including it here. [Ikarus Scheme](http://en.wikipedia.org/wiki/Ikarus_(Scheme_implementation)) is the actual implementation of Ghuloum's ideas, and appears to have been part of his Ph.D. work. It's supposed to be one of the first implementations of R6RS. I'm trying to install Ikarus now, but the configure script doesn't want to recognize my system's install of libgmp.so, so my problems are still unresolved. Example The following example seems to work in PLT 2.4.2 running in DrEd using the Pretty Big (require lang/plt-pretty-big) (load "/Users/donaldwakefield/ghuloum/tests/tests-driver.scm") (load "/Users/donaldwakefield/ghuloum/tests/tests-1.1-req.scm") (define (emit-program x) (unless (integer? x) (error "---")) (emit " .text") (emit " .globl scheme_entry") (emit " .type scheme_entry, @function") (emit "scheme_entry:") (emit " movl $~s, %eax" x) (emit " ret") ) Attempting to replace the require directive with #lang scheme results in the error message foo.scm:7:3: expand: unbound identifier in module in: emit which appears to be due to a failure to load tests-driver.scm. Attempting to use #lang r6rs disables the REPL, which I'd really like to use, so I'm going to try to continue with Pretty Big. My thanks to Eli Barzilay for his patient help.

Read the article
Default template parameters with forward declaration

- by Seth Johnson

Is it possible to forward declare a class that uses default arguments without specifying or knowing those arguments? For example, I would like to declare a boost::ptr_list< TYPE > in a Traits class without dragging the entire Boost library into every file that includes the traits. I would like to declare namespace boost { template<class T> class ptr_list< T >; }, but that doesn't work because it doesn't exactly match the true class declaration: template < class T, class CloneAllocator = heap_clone_allocator, class Allocator = std::allocator<void*> > class ptr_list { ... }; Are my options only to live with it or to specify boost::ptr_list< TYPE, boost::heap_clone_allocator, std::allocator<void*> in my traits class? (If I use the latter, I'll also have to forward declare boost::heap_clone_allocator and include <memory>, I suppose.) I've looked through Stroustrup's book, SO, and the rest of the internet and haven't found a solution. Usually people are concerned about not including STL, and the solution is "just include the STL headers." However, Boost is a much more massive and compiler-intensive library, so I'd prefer to leave it out unless I absolutely have to.

Read the article
In languages which create a new scope each time in a loop block, a new local copy of the local loop

- by Jian Lin

It seems that in language like C, Java, and Ruby (as opposed to Javascript), a new scope is created for each iteration of a loop block, and the local variable defined for the loop is actually made into a local variable every single time and recorded in this new scope? For example, in Ruby: p RUBY_VERSION $foo = [] (1..5).each do |i| $foo[i] = lambda { p i } end (1..5).each do |j| $foo[j].call() end the print out is: [MacBook01:~] $ ruby scope.rb "1.8.6" 1 2 3 4 5 [MacBook01:~] $ So, it looks like when a new scope is created, a new local copy of i is also created and recorded in this new scope, so that when the function is executed at a later time, the "i" is found in those scope chains as 1, 2, 3, 4, 5 respectively. Is this true? (It sounds like a heavy operation). Contrast that with p RUBY_VERSION $foo = [] i = 0 (1..5).each do |i| $foo[i] = lambda { p i } end (1..5).each do |j| $foo[j].call() end This time, the i is defined before entering the loop, so Ruby 1.8.6 will not put this i in the new scope created for the loop block, and therefore when the i is looked up in the scope chain, it always refer to the i that was in the outside scope, and give 5 every time: [MacBook01:~] $ ruby scope2.rb "1.8.6" 5 5 5 5 5 [MacBook01:~] $ I heard that in Ruby 1.9, i will be treated as a local defined for the loop even when there is an i defined earlier? The operation of creating a new scope, creating a new local copy of i each time through the loop seems heavy, as it seems it wouldn't have matter if we are not invoking the functions at a later time. So when the functions don't need to be invoked at a later time, could the interpreter and the compiler to C / Java try to optimize it so that there is not local copy of i each time?

Read the article
Am I Writing Assembly Or NASM?

- by cam

I'm fed up with this. I've been trying to just get a grip on assembly for awhile, but I feel like I'm coding towards my compiler rather than a language. I've been using this tutorial, and so far it's giving me hell. I'm using NASM, which may be the problem, but I figured it was the most popular one. I'm simply trying to learn the most general form of assembly, so I decided to learn x86. I keep running into stupid errors, like not being able to increment a variable. Here's the latest one: not being able to use div. mov bx, 0; mov cx, 0; jmp start; start: inc cx; mov ax, cx; div 3; <-- invalid combination of opcode and operand cmp ah,0; jz totalvalue; mov ax, cx; div 5; <-- invalid combination of opcode and operand cmp ah, 0; jz totalvalue; cmp cx, 1000; jz end; totalvalue: add bx,cx; jmp start; jmp end; end: mov ah,4ch; mov al,00; int 21h; Should I change compilers? It seems like division should be standard. Do I need to read two tutorials (one on NASM, and one on x86?). Any specific help on this problem?

Read the article
question/problem regarding assigning an array of char *

- by Fantastic Fourier

Hi I'm working with C and I have a question about assigning pointers. struct foo { int _bar; char * _car[MAXINT]; // this is meant to be an array of char * so that it can hold pointers to names of cars } int foofunc (void * arg) { int bar; char * car[MAXINT]; struct foo thing = (struct foo *) arg; bar = arg->_bar; // this works fine car = arg->_car; // this gives compiler errors of incompatible types in assignment } car and _car have same declaration so why am I getting an error about incompatible types? My guess is that it has something to do with them being pointers (because they are pointers to arrays of char *, right?) but I don't see why that is a problem. when i declared char * car; instead of char * car[MAXINT]; it compiles fine. but I don't see how that would be useful to me later when I need to access certain info using index, it would be very annoying to access that info later. in fact, I'm not even sure if I am going about the right way, maybe there is a better way to store a bunch of strings instead of using array of char *?

Read the article
How to find specific/local files via CMake

- by Andreas Romeyke

Hello, I have a problem with a locally installed library. In my project there is the xmlrpc++0.7-library: myproject/ +-- xmlrpc++0.7/ +-- src/ I want that CMake fallbacks using the local xmlrpc++0.7 directory if not found otherwise. Two problems, the first one, find_path() or find_library() does not work with local dir. I used a workaround testing if variables processed by find_xxx() are empty or not. If empty I set them manually. The cmake generates the Makefile without errors now. But if I want to compile the project via make, the c++ compiler returns "error: XmlRpc.h: file not found". The file XmlRpc.h lies in myproject/xmlrpc++0.7/src and if I compile all them manually it works fine. Here is my CMakeLists.txt. I am very happy if anyone could me point to the right solution to use cmake under conditions described above. --- CMakeLists.txt --- project(webservice_tesseract) cmake_minimum_required(VERSION 2.6) set(CMAKE_INCLUDE_CURRENT_DIR ON) # find tesseract find_path(TESSERACT_INCLUDE_DIR tesseract/tesseractmain.h /opt/local/include /usr/local/include /usr/include ) find_library(TESSERACT_LIBRARY_DIR NAMES tesseract_main PATHS /opt/local/lib/ /usr/local/lib/ /usr/lib ) message(STATUS "looked for tesseract library.") message(STATUS "Include file detected: [${TESSERACT_INCLUDE_DIR}].") message(STATUS "Lib file detected: [${TESSERACT_LIBRARY_DIR}].") add_library(tesseract STATIC IMPORTED) set_property(TARGET tesseract PROPERTY IMPORTED_LOCATION ${TESSERACT_LIBRARY_DIR}/libtesseractmain.a ) #find xmlrpc++ message(STATUS "cmake home dir: [${CMAKE_HOME_DIRECTORY}].") set(LOCAL_XMLRPCPLUSPLUS ${CMAKE_HOME_DIRECTORY}/xmlrpc0.7++/) message(STATUS "xmlrpc++ local dir: [${LOCAL_XMLRPCPLUSPLUS}].") find_path(XMLRPCPLUSPLUS_INCLUDE_DIR XmlRpcServer.h ${LOCAL_XMLRPCPLUSPLUS}src /opt/local/include /usr/local/include /usr/include ) find_library(XMLRPCPLUSPLUS_LIBRARY_DIR NAMES XmlRpc PATHS ${LOCAL_XMLRPCPLUSPLUS} /opt/local/lib/ /usr/local/lib/ /usr/lib/ ) # next lines are an ugly workaround because cmake find_xxx() does not find local stuff if (XMLRPCPLUSPLUS_INCLUDE_DIR) else (XMLRPCPLUSPLUS_INCLUDE_DIR) set(XMLRPCPLUSPLUS_INCLUDE_DIR ${LOCAL_XMLRPCPLUSPLUS}src) endif (XMLRPCPLUSPLUS_INCLUDE_DIR) if (XMLRPCPLUSPLUS_LIBRARY_DIR) else (XMLRPCPLUSPLUS_LIBRARY_DIR) set(XMLRPCPLUSPLUS_LIBRARY_DIR ${LOCAL_XMLRPCPLUSPLUS}) endif (XMLRPCPLUSPLUS_LIBRARY_DIR) message(STATUS "looked for xmlrpc++ library.") message(STATUS "Include file detected: [${XMLRPCPLUSPLUS_INCLUDE_DIR}].") message(STATUS "Lib file detected: [${XMLRPCPLUSPLUS_LIBRARY_DIR}].") add_library(xmlrpc STATIC IMPORTED) set_property(TARGET xmlrpc PROPERTY IMPORTED_LOCATION ${XMLRPCPLUSPLUS_LIBRARY_DIR}/libXmlRpc.a ) #### link together include_directories(${XMLRPCPLUSPLUS_INCLUDE_DIR} ${TESSERACT_INCLUDE_DIR}) link_directories(${XMLRPCPLUSPLUS_LIBRARY_DIR} ${TESSERACT_LIBRARY_DIR}) add_library(simpleocr STATIC simple_ocr.cpp) add_executable(webservice_tesseract webservice.cpp) target_link_libraries(webservice_tesseract xmlrpc tesseract simpleocr)

Read the article
How close can I get C# to the performance of C++ for small intensive tasks?

- by SLC

I was thinking about the speed difference of C++ to C# being mostly about C# compiling to byte-code that is taken in by the JIT compiler (is that correct?) and all the checks C# does. I notice that it is possible to turn a lot of these functions off, both in the compile options, and possibly through using the unsafe keyword as unsafe code is not verifiable by the common language runtime. Therefore if you were to write a simple console application in both languages, that flipped an imaginary coin an infinite number of times and displayed the results to the screen every 10,000 or so iterations, how much speed difference would there be? I chose this because it's a very simple program. I'd like to test this but I don't know C++ or have the tools to compile it. This is my C# version though: static void Main(string[] args) { unsafe { Random rnd = new Random(); int heads = 0, tails = 0; while (true) { if (rnd.NextDouble() > 0.5) heads++; else tails++; if ((heads + tails) % 1000000 == 0) Console.WriteLine("Heads: {0} Tails: {1}", heads, tails); } } } Is the difference enough to warrant deliberately compiling sections of code "unsafe" or into DLLs that do not have some of the compile options like overflow checking enabled? Or does it go the other way, where it would be beneficial to compile sections in C++? I'm sure interop speed comes into play too then. To avoid subjectivity, I reiterate the specific parts of this question as: Does C# have a performance boost from using unsafe code? Do the compile options such as disabling overflow checking boost performance, and do they affect unsafe code? Would the program above be faster in C++ or negligably different? Is it worth compiling long intensive number-crunching tasks in a language such as C++ or using /unsafe for a bonus? Less subjectively, could I complete an intensive operation faster by doing this?

Read the article
rewrite not a member of LiftRules

- by José Leal

Hi guys, I was following http://www.assembla.com/wiki/show/liftweb/URL_Rewriting tutorial for url rewritting in liftweb.. but I get this error: error: value rewrite is not a member of object net.liftweb.http.LiftRules .. it is really odd.. and the documentation says that it exists. I'm using idea IDE, and I've done everything from scratch, using the lift maven blank archifact. Some more info: [INFO] ------------------------------------------------------------------------ [INFO] Building Joseph3 [INFO] task-segment: [tomcat:run] [INFO] ------------------------------------------------------------------------ [INFO] Preparing tomcat:run [INFO] [resources:resources {execution: default-resources}] [WARNING] Using platform encoding (UTF-8 actually) to copy filtered resources, i.e. build is platform dependent! [INFO] Copying 0 resource [INFO] [yuicompressor:compress {execution: default}] [INFO] nb warnings: 0, nb errors: 0 [INFO] artifact org.mortbay.jetty:jetty: checking for updates from scala-tools.org [INFO] artifact org.mortbay.jetty:jetty: checking for updates from central [INFO] [compiler:compile {execution: default-compile}] [INFO] Nothing to compile - all classes are up to date [INFO] [scala:compile {execution: default}] [INFO] Checking for multiple versions of scala [INFO] /home/dpz/Scala/Doit/Joseph3/src/main/scala:-1: info: compiling [INFO] Compiling 2 source files to /home/dpz/Scala/Doit/Joseph3/target/classes at 1274922123910 [ERROR] /home/dpz/Scala/Doit/Joseph3/src/main/scala/bootstrap/liftweb/Boot.scala:16: error: value rewrite is not a member of object net.liftweb.http.LiftRules [INFO] LiftRules.rewrite.prepend(NamedPF("ProductExampleRewrite") { [INFO] ^ [ERROR] one error found [INFO] ------------------------------------------------------------------------ [ERROR] BUILD ERROR [INFO] ------------------------------------------------------------------------ [INFO] wrap: org.apache.commons.exec.ExecuteException: Process exited with an error: 1(Exit value: 1) [INFO] ------------------------------------------------------------------------ [INFO] For more information, run Maven with the -e switch [INFO] ------------------------------------------------------------------------ [INFO] Total time: 19 seconds [INFO] Finished at: Thu May 27 03:02:07 CEST 2010 [INFO] Final Memory: 20M/175M [INFO] ------------------------------------------------------------------------ Process finished with exit code 1 enter code here

Read the article
C++ Returning a Reference

- by Devil Jin

Consider the following code where I am returning double& and a string&. The thing works fine in the case of a double but not in the case of a string. Why is this difference in the behavior? In both the cases compiler does not even throws the Warning: returning address of local variable or temporary as I am returning a reference. #include <iostream> #include <string> using namespace std; double &getDouble(){ double h = 46.5; double &hours = h; return hours; } string &getString(){ string str = "Devil Jin"; string &refStr = str; return refStr; } int main(){ double d = getDouble(); cout << "Double = " << d << endl; string str = getString(); cout << "String = " << str.c_str() << endl; return 0; } Output: $ ./a.exe Double = 46.5 String =

Read the article
Can't install egenix-mx-base on Django production VPS

- by Shane

I have been following these instructions for setting up a Django production server with postgres, apache, nginx, and memcache. My problem is that I cannot get egenix-mx-base to install and without this I cannot get psycopg2 to work and therefore no database access :(. I am attempting this on a VPS running a clean install of Ubuntu Hardy (8.04) and have followed all instructions on the site to a T. The error message is as follows: $ easy_install egenix-mx-base Searching for egenix-mx-base Reading http://pypi.python.org/simple/egenix-mx-base/ Reading http://www.egenix.com/products/python/mxBase/ Reading http://www.lemburg.com/python/mxExtensions.html Reading http://www.egenix.com/ Best match: egenix-mx-base 3.1.3 Downloading http://downloads.egenix.com/python/egenix-mx-base-3.1.3.tar.gz Processing egenix-mx-base-3.1.3.tar.gz Running egenix-mx-base-3.1.3/setup.py -q bdist_egg --dist-dir /tmp/easy_install-iF7qzl/egenix-mx-base-3.1.3/egg-dist-tmp-laxvcS Warning: Can't read registry to find the necessary compiler setting Make sure that Python modules _winreg, win32api or win32con are installed. In file included from mx/TextTools/mxTextTools/mxte.c:42: mx/TextTools/mxTextTools/mxte_impl.h: In function ‘mxTextTools_TaggingEngine’: mx/TextTools/mxTextTools/mxte_impl.h:345: warning: pointer targets in initialization differ in signedness mx/TextTools/mxTextTools/mxte_impl.h:364: warning: pointer targets in initialization differ in signedness mx/URL/mxURL/mxURL.c: In function ‘mxURL_SetFromString’: mx/URL/mxURL/mxURL.c:676: warning: pointer targets in initialization differ in signedness mx/UID/mxUID/mxUID.c: In function ‘mxUID_Verify’: mx/UID/mxUID/mxUID.c:333: warning: pointer targets in passing argument 1 of ‘sscanf’ differ in signedness mx/UID/mxUID/mxUID.c: In function ‘mxUID_New’: mx/UID/mxUID/mxUID.c:462: warning: pointer targets in passing argument 1 of ‘mxUID_CRC16’ differ in signedness error: Setup script exited with error: build/bdist.linux-x86_64-py2.5_ucs4/dumb/egenix_mx_base-3.1.3-py2.5.egg-info: Is a directory Thank you to anyone who takes the time to try to help me.

Read the article
ASP.NET MVC + MySql Membership Provider, user cannot login

- by Jason Miesionczek

Hello, I've been playing around with using MySql as the membership provider for asp.net mvc forms authentication. I've got things configured correctly as far as i can tell, and i can create users via both the register action and asp.net web config site. however, when i try to login with one of the users, it does not work. it returns an error as if i had entered a wrong password, or if the account doesn't exist. i have verified in the database that the account does exist. I've followed the instructions here for reference: http://blog.tchami.com/post/ASPNET-MVC-2-and-MySQL-Membership-Provider.aspx here is my web.config: <?xml version="1.0"?>  <configuration> <connectionStrings> <add name="MySQLConn" connectionString="Server=localhost;Database=intereditor;Uid=<user>;Pwd=<password>;"/> </connectionStrings> <system.web> <compilation debug="true" targetFramework="4.0"> <assemblies> <add assembly="System.Web.Abstractions, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" /> <add assembly="System.Web.Routing, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" /> <add assembly="System.Web.Mvc, Version=2.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" /> </assemblies> </compilation> <authentication mode="Forms"> <forms loginUrl="~/Account/LogOn" timeout="2880" name=".ASPXFORM$" path="/" requireSSL="false" slidingExpiration="true" enableCrossAppRedirects="false" /> </authentication> <membership defaultProvider="MySqlMembershipProvider"> <providers> <clear/> <add name="MySqlMembershipProvider" type="MySql.Web.Security.MySQLMembershipProvider,MySql.Web,Version=6.3.4.0, Culture=neutral,PublicKeyToken=c5687fc88969c44d" autogenerateschema="true" connectionStringName="MySQLConn" enablePasswordRetrieval="false" enablePasswordReset="true" requiresQuestionAndAnswer="false" requiresUniqueEmail="false" passwordFormat="Hashed" maxInvalidPasswordAttempts="5" minRequiredPasswordLength="6" minRequiredNonalphanumericCharacters="0" passwordAttemptWindow="10" passwordStrengthRegularExpression="" applicationName="/" /> </providers> </membership> <profile defaultProvider="MySqlProfileProvider"> <providers> <clear/> <add name="MySqlProfileProvider" type="MySql.Web.Profile.MySQLProfileProvider,MySql.Web,Version=6.3.4.0,Culture=neutral,PublicKeyToken=c5687fc88969c44d" connectionStringName="MySQLConn" applicationName="/" /> </providers> </profile> <roleManager enabled="true" defaultProvider="MySqlRoleProvider"> <providers> <clear /> <add name="MySqlRoleProvider" type="MySql.Web.Security.MySQLRoleProvider,MySql.Web,Version=6.3.4.0,Culture=neutral,PublicKeyToken=c5687fc88969c44d" connectionStringName="MySQLConn" applicationName="/" /> </providers> </roleManager> <pages> <namespaces> <add namespace="System.Web.Mvc" /> <add namespace="System.Web.Mvc.Ajax" /> <add namespace="System.Web.Mvc.Html" /> <add namespace="System.Web.Routing" /> </namespaces> </pages> </system.web> <system.webServer> <validation validateIntegratedModeConfiguration="false"/> <modules runAllManagedModulesForAllRequests="true"/> </system.webServer> <runtime> <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1"> <dependentAssembly> <assemblyIdentity name="System.Web.Mvc" publicKeyToken="31bf3856ad364e35" /> <bindingRedirect oldVersion="1.0.0.0" newVersion="2.0.0.0" /> </dependentAssembly> </assemblyBinding> </runtime> </configuration> Can anyone please help me identify what is wrong so that users can login? UPDATE So after debugging the login process in the code of the membership provider itself, i discovered that there is a bug in the provider. There is a discrepancy between the password hash that is stored in the database, and the has that is generated based on the inputted password. As a workaround for my issue, i changed the password format to 'encrpyted' and added a machine key to my web.config. I am still interested in figuring out the issue with the hashed format in the provider, and will spend some more time debugging it, and if i can figure out the problem, i will put together a patch and submit it.

Read the article
Ambiguous access to base class template member function

- by Johann Gerell

In Visual Studio 2008, the compiler cannot resolve the call to SetCustomer in _tmain below and make it unambiguous: template <typename TConsumer> struct Producer { void SetConsumer(TConsumer* consumer) { consumer_ = consumer; } TConsumer* consumer_; }; struct AppleConsumer { }; struct MeatConsumer { }; struct ShillyShallyProducer : public Producer<AppleConsumer>, public Producer<MeatConsumer> { }; int _tmain(int argc, _TCHAR* argv[]) { ShillyShallyProducer producer; AppleConsumer consumer; producer.SetConsumer(&consumer); // <--- Ambiguous call!! return 0; } This is the compilation error: // error C2385: ambiguous access of 'SetConsumer' // could be the 'SetConsumer' in base 'Producer<AppleConsumer>' // or could be the 'SetConsumer' in base 'Producer<MeatConsumer>' I thought the template argument lookup mechanism would be smart enough to deduce the correct base Producer. Why isn't it? I could get around this by changing Producer to template <typename TConsumer> struct Producer { template <typename TConsumer2> void SetConsumer(TConsumer2* consumer) { consumer_ = consumer; } TConsumer* consumer_; }; and call SetConsumer as producer.SetConsumer<AppleConsumer>(&consumer); // Unambiguous call!! but it would be nicer if I didn't have to...

Read the article
Why does autoboxing in Java allow me to have 3 possible values for a boolean?

- by John

Reference: http://java.sun.com/j2se/1.5.0/docs/guide/language/autoboxing.html If your program tries to autounbox null, it will throw a NullPointerException. javac will give you a compile-time error if you try to assign null to a boolean. makes sense. assigning null to a Boolean is a-ok though. also makes sense, i guess. but let's think about the fact that you'll get a NPE when trying to autounbox null. what this means is that you can't safely perform boolean operations on Booleans without null-checking or exception handling. same goes for doing math operations on an Integer. for a long time, i was a fan of autoboxing in java1.5+ because I thought it got java closer to be truly object-oriented. but, after running into this problem last night, i gotta say that i think this sucks. the compiler giving me an error when I'm trying to do stuff with an uninitialized primitive is a good thing. I think I may be misunderstanding the point of autoboxing, but at the same time I will never accept that a boolean should be able to have 3 values. can anyone explain this? what am i not getting?

Read the article
How to force the build to be out of date, when a text file is modified?

- by demoncodemonkey

The Scenario My project has a post-build phase set up to run a batch file, which reads a text file "version.txt". The batch file uses the information in version.txt to inject the DLL with a version block using this tool. The version.txt is included in my project to make it easy to modify. It looks a bit like this: @set #Description="TankFace Utility Library" @set #FileVersion="0.1.2.0" @set #Comments="" Basically the batch file renames this file to version.bat, calls it, then renames it back to version.txt afterwards. The Problem When I modify version.txt (e.g. to increment the file version), and then press F7, the build is not seen as out-of-date, so the post-build step is not executed, so the DLL's version doesn't get updated. I really want to include the .txt file as an input to the build, but without anything actually trying to use it. If I #include the .txt file from a CPP file in the project, the compiler fails because it obviously doesn't understand what "@set" means. If I add /* ... */ comments around the @set commands, then the batch file has some syntax errors but eventually succeeds. But this is a poor solution I think. So... how would you do it?

Read the article
Use Objective-C without NSObject?

- by Alex I

I am testing some simple Objective-C code on Windows (cygwin, gcc). This code already works in Xcode on Mac. I would like to convert my objects to not subclass NSObject (or anything else, lol). Is this possible, and how? What I have so far: // MyObject.h @interface MyObject - (void)myMethod:(int) param; @end and // MyObject.m #include "MyObject.h" @interface MyObject() { // this line is a syntax error, why? int _field; } @end @implementation MyObject - (id)init { // what goes in here? return self; } - (void)myMethod:(int) param { _field = param; } @end What happens when I try compiling it: gcc -o test MyObject.m -lobjc MyObject.m:4:1: error: expected identifier or ‘(’ before ‘{’ token MyObject.m: In function ‘-[MyObject myMethod:]’: MyObject.m:17:3: error: ‘_field’ undeclared (first use in this function) EDIT My compiler is cygwin's gcc, also has cygwin gcc-objc package: gcc --version gcc (GCC) 4.7.3 I have tried looking for this online and in a couple of Objective-C tutorials, but every example of a class I have found inherits from NSObject. Is it really impossible to write Objective-C without Cocoa or some kind of Cocoa replacement that provides NSObject? (Yes, I know about GNUstep. I would really rather avoid that if possible...)

Read the article
Calling a method on an unitialized object (null pointer)

- by Florin

What is the normal behavior in Objective-C if you call a method on an object (pointer) that is nil (maybe because someone forgot to initialize it)? Shouldn't it generate some kind of an error (segmentation fault, null pointer exception...)? If this is normal behavior, is there a way of changing this behavior (by configuring the compiler) so that the program raises some kind of error / exception at runtime? To make it more clear what I am talking about, here's an example. Having this class: @interface Person : NSObject { NSString *name; } @property (nonatomic, retain) NSString *name; - (void)sayHi; @end with this implementation: @implementation Person @synthesize name; - (void)dealloc { [name release]; [super dealloc]; } - (void)sayHi { NSLog(@"Hello"); NSLog(@"My name is %@.", name); } @end Somewhere in the program I do this: Person *person = nil; //person = [[Person alloc] init]; // let's say I comment this line person.name = @"Mike"; // shouldn't I get an error here? [person sayHi]; // and here [person release]; // and here

Read the article
With PascalMock how do I mock a method with an untyped out parameter and an open array parameter?

- by Oliver Giesen

I'm currently in the process of getting started with unit testing and mocking for good and I stumbled over the following method that I can't seem to fabricate a working mock implementation for: function GetInstance(const AIID: TGUID; out AInstance; const AArgs: array of const; const AContextID: TImplContextID = CID_DEFAULT): Boolean; (TImplContextID is just an alias for Integer) I thought it would have to look something like this: function TImplementationProviderMock.GetInstance( const AIID: TGUID; out AInstance; const AArgs: array of const; const AContextID: TImplContextID): Boolean; begin Result := AddCall('GetInstance') .WithParams([@AIID, AContextID]) .ReturnsOutParams([AInstance]) .ReturnValue; end; But the compiler complains about the .ReturnsOutParams([AInstance]) saying "Bad argument type in variable type array constructor.". Also I haven't found a way to specify the open array parameter AArgs at all. Also, is using the @-notation for the TGUID-typed parameter the right way to go? Is it possible to mock this method with the current version of PascalMock at all?

Read the article
PHP autoloader: ignoring non-existing include

- by Bart van Heukelom

I have a problem with my autoloader: public function loadClass($className) { $file = str_replace(array('_', '\\'), '/', $className) . '.php'; include_once $file; } As you can see, it's quite simple. I just deduce the filename of the class and try to include it. I have a problem though; I get an exception when trying to load a non-existing class (because I have an error handler which throws exceptions). This is inconvenient, because it's also fired when you use class_exists() on a non-existing class. You don't want an exception there, just a "false" returned. I fixed this earlier by putting an @ before the include (supressing all errors). The big drawback with this, though, is that any parser/compiler errors (that are fatal) in this include won't show up (not even in the logs), resulting in a hard to find bug. What would be the best way to solve both problems at once? The easiest way would be to include something like this in the autoloader (pseudocode): foreach (path in the include_path) { if (is_readable(the path + the class name)) readable = true; } if (!readable) return; But I worry about the performance there. Would it hurt a lot? (Solved) Made it like this: public function loadClass($className) { $file = str_replace(array('_', '\\'), '/', $className) . '.php'; $paths = explode(PATH_SEPARATOR, get_include_path()); foreach ($paths as $path) { if (is_readable($path . '/' . $file)) { include_once $file; return; } } }

Read the article

< Previous Page | 153 154 155 156 157 158 159 160 161 162 163 164 | Next Page >