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  • Creating and using a static lib in xcode (MacOSX)

    - by Alasdair Morrison
    I am trying to create a static library in xcode and link to that static library from another program. So as a test i have created a BSD static C library project and just added the following code: //Test.h int testFunction(); //Test.cpp #include "Test.h" int testFunction() { return 12; } This compiles fine and create a .a file (libTest.a). Now i want to use it in another program so I create a new xcode project (cocoa application) Have the following code: //main.cpp #include <iostream> #include "Testlib.h" int main (int argc, char * const argv[]) { // insert code here... std::cout << "Result:\n" <<testFunction(); return 0; } //Testlib.h extern int testFunction(); I right clicked on the project - add - existing framework - add other Selected the .a file and it added it into the project view. I always get this linker error: Build TestUselibrary of project TestUselibrary with configuration Debug Ld build/Debug/TestUselibrary normal x86_64 cd /Users/myname/location/TestUselibrary setenv MACOSX_DEPLOYMENT_TARGET 10.6 /Developer/usr/bin/g++-4.2 -arch x86_64 -isysroot /Developer/SDKs/MacOSX10.6.sdk -L/Users/myname/location/TestUselibrary/build/Debug -L/Users/myname/location/TestUselibrary/../Test/build/Debug -F/Users/myname/location/TestUselibrary/build/Debug -filelist /Users/myname/location/TestUselibrary/build/TestUselibrary.build/Debug/TestUselibrary.build/Objects-normal/x86_64/TestUselibrary.LinkFileList -mmacosx-version-min=10.6 -lTest -o /Users/myname/location/TestUselibrary/build/Debug/TestUselibrary Undefined symbols: "testFunction()", referenced from: _main in main.o ld: symbol(s) not found collect2: ld returned 1 exit status I am new to macosx development and fairly new to c++. I am probably missing something fairly obvious, all my experience comes from creating dlls on the windows platform. I really appreciate any help.

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  • Static variable for communication among like-typed objects

    - by Dan Ray
    I have a method that asynchronously downloads images. If the images are related to an array of objects (a common use-case in the app I'm building), I want to cache them. The idea is, I pass in an index number (based on the indexPath.row of the table I'm making by way through), and I stash the image in a static NSMutableArray, keyed on the row of the table I'm dealing with. Thusly: @implementation ImageDownloader ... @synthesize cacheIndex; static NSMutableArray *imageCache; -(void)startDownloadWithImageView:(UIImageView *)imageView andImageURL:(NSURL *)url withCacheIndex:(NSInteger)index { self.theImageView = imageView; self.cacheIndex = index; NSLog(@"Called to download %@ for imageview %@", url, self.theImageView); if ([imageCache objectAtIndex:index]) { NSLog(@"We have this image cached--using that instead"); self.theImageView.image = [imageCache objectAtIndex:index]; return; } self.activeDownload = [NSMutableData data]; NSURLConnection *conn = [[NSURLConnection alloc] initWithRequest:[NSURLRequest requestWithURL:url] delegate:self]; self.imageConnection = conn; [conn release]; } //build up the incoming data in self.activeDownload with calls to didReceiveData... - (void)connectionDidFinishLoading:(NSURLConnection *)connection { NSLog(@"Finished downloading."); UIImage *image = [[UIImage alloc] initWithData:self.activeDownload]; self.theImageView.image = image; NSLog(@"Caching %@ for %d", self.theImageView.image, self.cacheIndex); [imageCache insertObject:image atIndex:self.cacheIndex]; NSLog(@"Cache now has %d items", [imageCache count]); [image release]; } My index is getting through okay, I can see that by my NSLog output. But even after my insertObject: atIndex: call, [imageCache count] never leaves zero. This is my first foray into static variables, so I presume I'm doing something wrong. (The above code is heavily pruned to show only the main thing of what's going on, so bear that in mind as you look at it.)

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  • Creating and using a static lib in xcode

    - by Alasdair Morrison
    I am trying to create a static library in xcode and link to that static library from another program. So as a test i have created a BSD static C library project and just added the following code: //Test.h int testFunction(); //Test.cpp #include "Test.h" int testFunction() { return 12; } This compiles fine and create a .a file (libTest.a). Now i want to use it in another program so I create a new xcode project (cocoa application) Have the following code: //main.cpp #include <iostream> #include "Testlib.h" int main (int argc, char * const argv[]) { // insert code here... std::cout << "Result:\n" <<testFunction(); return 0; } //Testlib.h extern int testFunction(); I right clicked on the project - add - existing framework - add other Selected the .a file and it added it into the project view. I always get this linker error: Build TestUselibrary of project TestUselibrary with configuration Debug Ld build/Debug/TestUselibrary normal x86_64 cd /Users/myname/location/TestUselibrary setenv MACOSX_DEPLOYMENT_TARGET 10.6 /Developer/usr/bin/g++-4.2 -arch x86_64 -isysroot /Developer/SDKs/MacOSX10.6.sdk -L/Users/myname/location/TestUselibrary/build/Debug -L/Users/myname/location/TestUselibrary/../Test/build/Debug -F/Users/myname/location/TestUselibrary/build/Debug -filelist /Users/myname/location/TestUselibrary/build/TestUselibrary.build/Debug/TestUselibrary.build/Objects-normal/x86_64/TestUselibrary.LinkFileList -mmacosx-version-min=10.6 -lTest -o /Users/myname/location/TestUselibrary/build/Debug/TestUselibrary Undefined symbols: "testFunction()", referenced from: _main in main.o ld: symbol(s) not found collect2: ld returned 1 exit status I am new to macosx development and fairly new to c++. I am probably missing something fairly obvious, all my experience comes from creating dlls on the windows platform. I really appreciate any help.

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  • PHP: Get instance of static class by string value

    - by Tirithen
    I'm working on a php web api that was handed to me with a lot of code that needs to be refactored. The ones that wrote the code wanted to include a static configuration class to an api resource and then get an instance of that class something like this: <?php $obj = "User"; $confObjectSuffix = "_conf"; $confObject = $obj.$confObjectSuffix; if ($confObject::inst()->checkMethod($method)) { ..... This gives the error "Parse error: syntax error, unexpected T_PAAMAYIM_NEKUDOTAYIM in ....." since $confObject is a string and not a object. I wrote some testcode: <?php $class = "User_conf"; echo "<pre>"; print_r($$class::Inst()); echo "</pre>"; class User_conf { private static $INSTANCE = null; public static function Inst() { if(User_conf::$INSTANCE === null) { User_conf::$INSTANCE = new User_conf(); } return User_conf::$INSTANCE; } } But can't get it to work with $$ either, is there some other way around this? I don't want to rewrite more than necessary.

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  • [Qt] How to get rid of OCI.dll dependency when compiling static

    - by STL
    Hi, My application accesses an Oracle database through Qt's QSqlDatabase class. I'm compiling Qt as static for the release build, but I can't seem to be able to get rid of OCI.dll dependency. I'm trying to link against oci.lib (as available in Oracle's Instant Client with SDK). Here's my configure line : configure -qt-libjpeg -qt-zlib -qt-libpng -nomake examples -nomake demos -no-exceptions -no-stl -no-rtti -no-qt3support -no-scripttools -no-openssl -no-opengl -no-phonon -no-style-motif -no-style-cde -no-style-cleanlooks -no-style-plastique -static -release -opensource -plugin-sql-oci -plugin-sql-sqlite -platform win32-msvc2005 I link against oci.h and oci.lib in the SDK's folder by using : set INCLUDE=C:\oracle\instantclient\sdk\include;%INCLUDE% set LIB=C:\oracle\instantclient\sdk\lib\msvc;%LIB% Then, once Qt is compiled, I use the following lines in my *.pro file : QT += sql CONFIG += static LIBS += C:\oracle\instantclient\sdk\lib\msvc\oci.lib QTPLUGIN += qsqloci Then, in my main.cpp, I add the following commands to statically compile OCI plugin in the application : #include <QtPlugin> Q_IMPORT_PLUGIN(qsqloci) After compiling the project, I test it on my workstation and it works (as I have Oracle Instant Client installed). When I try on another workstation, I always get the message: This application has failed to start because OCI.dll was not found. Re-installing this application may fix this problem. I don't understand why I still need OCI.dll, as my statically linked application is supposed to link to oci.lib instead. Is there any Qt people here that might have a solution for me ? Thanks a lot ! STL

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  • Static library not included in resulting LLVM executable

    - by Matthew Glubb
    Hi, I am trying to compile a c program using LLVM and I am having trouble getting some static libraries included. I have successfully compiled those static libraries using LLVM and, for example, libogg.a is present, as is ogg.l.bc. However, when I try to build the final program, it does not include the static ogg library. I've tried various compiler options with the most notable being: gcc oggvorbis.c -O3 -Wall -I$OV_DIR/include -l$OV_DIR/lib/libogg.a -l$OV_DIR/lib/libvorbis.a -o test.exe This results in the following output (directories shortened for brevity): $OV_DIR/include/vorbis/vorbisfile.h:75: warning: ‘OV_CALLBACKS_DEFAULT’ defined but not used $OV_DIR/include/vorbis/vorbisfile.h:82: warning: ‘OV_CALLBACKS_NOCLOSE’ defined but not used $OV_DIR/include/vorbis/vorbisfile.h:89: warning: ‘OV_CALLBACKS_STREAMONLY’ defined but not used $OV_DIR/include/vorbis/vorbisfile.h:96: warning: ‘OV_CALLBACKS_STREAMONLY_NOCLOSE’ defined but not used llvm-ld: warning: Cannot find library '$OV_DIR/lib/ogg.l.bc' llvm-ld: warning: Cannot find library '$OV_DIR/lib/vorbis.l.bc' WARNING: While resolving call to function 'main' arguments were dropped! I find this perplexing because $OV_DIR/lib/ogg.l.bc DOES exit, as does vorbis.l.bc and they are both readable (as are their containing directories) by everyone. Does anyone have any idea with what I am doing wrong? Thanks, Matt

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  • Questions about serving static files from a servlet

    - by Geo
    I'm very new to servlets. I'd like to serve some static files, some css and some javascript. Here's what I got so far: in web.xml: <servlet> <description></description> <display-name>StaticServlet</display-name> <servlet-name>StaticServlet</servlet-name> <servlet-class>StaticServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>StaticServlet</servlet-name> <url-pattern>/static/*</url-pattern> </servlet-mapping> I'm assuming in the StaticServlet I'd have to work with request.getPathInfo to see what was requested, get a mime type, read the file & write it to the client. If this is not the way to go, or is not a viable way of doing things, please suggest a better way. I'm not really sure where to place the static directory, because if I try to print new File(".") it gives me the directory of my Eclipse installation. Is there a way to find out the project's directory?

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  • noncopyable static const member class in template class

    - by Dukales
    I have a non-copyable (inherited from boost::noncopyable) class that I use as a custom namespace. Also, I have another class, that uses previous one, as shown here: #include <boost/utility.hpp> #include <cmath> template< typename F > struct custom_namespace : boost::noncopyable { F sqrt_of_half(F const & x) const { using std::sqrt; return sqrt(x / F(2.0L)); } // ... maybe others are not so dummy const/constexpr methods }; template< typename F > class custom_namespace_user { static ::custom_namespace< F > const custom_namespace_; public : F poisson() const { return custom_namespace_.sqrt_of_half(M_PI); } static F square_diagonal(F const & a) { return a * custom_namespace_.sqrt_of_half(1.0L); } }; template< typename F > ::custom_namespace< F > const custom_namespace_user< F >::custom_namespace_(); this code leads to the next error (even without instantiation): error: no 'const custom_namespace custom_namespace_user::custom_namespace_()' member function declared in class 'custom_namespace_user' The next way is not legitimate: template< typename F ::custom_namespace< F const custom_namespace_user< F ::custom_namespace_ = ::custom_namespace< F (); What should I do to declare this two classes (first as noncopyable static const member class of second)? Is this feaseble?

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  • Java Best Practice for type resolution at runtime.

    - by Brian
    I'm trying to define a class (or set of classes which implement the same interface) that will behave as a loosely typed object (like JavaScript). They can hold any sort of data and operations on them depend on the underlying type. I have it working in three different ways but none seem ideal. These test versions only allow strings and integers and the only operation is add. Adding integers results in the sum of the integer values, adding strings concatenates the strings and adding an integer to a string converts the integer to a string and concatenates it with the string. The final version will have more types (Doubles, Arrays, JavaScript-like objects where new properties can be added dynamically) and more operations. Way 1: public interface DynObject1 { @Override public String toString(); public DynObject1 add(DynObject1 d); public DynObject1 addTo(DynInteger1 d); public DynObject1 addTo(DynString1 d); } public class DynInteger1 implements DynObject1 { private int value; public DynInteger1(int v) { value = v; } @Override public String toString() { return Integer.toString(value); } public DynObject1 add(DynObject1 d) { return d.addTo(this); } public DynObject1 addTo(DynInteger1 d) { return new DynInteger1(d.value + value); } public DynObject1 addTo(DynString1 d) { return new DynString1(d.toString()+Integer.toString(value)); } } ...and similar for DynString1 Way 2: public interface DynObject2 { @Override public String toString(); public DynObject2 add(DynObject2 d); } public class DynInteger2 implements DynObject2 { private int value; public DynInteger2(int v) { value = v; } @Override public String toString() { return Integer.toString(value); } public DynObject2 add(DynObject2 d) { Class c = d.getClass(); if(c==DynInteger2.class) { return new DynInteger2(value + ((DynInteger2)d).value); } else { return new DynString2(toString() + d.toString()); } } } ...and similar for DynString2 Way 3: public class DynObject3 { private enum ObjectType { Integer, String }; Object value; ObjectType type; public DynObject3(Integer v) { value = v; type = ObjectType.Integer; } public DynObject3(String v) { value = v; type = ObjectType.String; } @Override public String toString() { return value.toString(); } public DynObject3 add(DynObject3 d) { if(type==ObjectType.Integer && d.type==ObjectType.Integer) { return new DynObject3(Integer.valueOf(((Integer)value).intValue()+((Integer)value).intValue())); } else { return new DynObject3(value.toString()+d.value.toString()); } } } With the if-else logic I could use value.getClass()==Integer.class instead of storing the type but with more types I'd change this to use a switch statement and Java doesn't allow switch to use Classes. Anyway... My question is what is the best way to go about something thike this?

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  • Initialize Static Array of Structs in C

    - by russell_h
    I implementing a card game in C. There are lots of types of cards and each has a bunch of information, including some actions that will need to be individually scripted associated with it. Given a struct like this (and I'm not certain I have the syntax right for the function pointer) struct CARD { int value; int cost; // This is a pointer to a function that carries out actions unique // to this card int (*do_actions) (struct GAME_STATE *state, int choice1, int choice2); }; I would like to initialize a static array of these, one for each card. I'm guessing this would look something like this int do_card0(struct GAME_STATE *state, int choice1, int choice2) { // Operate on state here } int do_card1(struct GAME_STATE *state, int choice1, int choice2) { // Operate on state here } extern static struct cardDefinitions[] = { {0, 1, do_card0}, {1, 3, do_card1} }; Will this work, and am I going about this the right way at all? I'm trying to avoid huge numbers of switch statements. Do I need to define the 'do_cardN' functions ahead of time, or is there some way to define them inline in the initialization of the struct (something like a lambda function in python)? I'll need read-only access to cardDefinitions from a different file - is 'extern static' correct for that? I know this is a lot of questions rolled into one but I'm really a bit vague about how to go about this. Thanks.

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  • C++: static assert for const variables?

    - by shoosh
    Static asserts are very convenient for checking things in compile time. A simple static assert idiom looks like this: template<bool> struct StaticAssert; template<> struct StaticAssert<true> {}; #define STATIC_ASSERT(condition) do { StaticAssert<condition>(); } while(0) This is good for stuff like STATIC_ASSERT(sizeof(float) == 4) and: #define THIS_LIMIT (1000) ... STATIC_ASSERT(THIS_LIMIT > OTHER_LIMIT); But using #define is not the "C++" way of defining constants. C++ would have you use an anonymous namespace: namespace { const int THIS_LIMIT = 1000; } or even: static const int THIS_LIMIT = 1000; The trouble with this is that with a const int you can't use STATIC_ASSERT() and you must resort to a run-time check which is silly. Is there a way to properly solve this in current C++? I think I've read C++0x has some facility to do this...

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  • static variable lose its value

    - by user542719
    I have helper class with this static variable that is used for passing data between two classes. public class Helper{ public static String paramDriveMod;//this is the static variable in first calss } this variable is used in following second class mathod public void USB_HandleMessage(char []USB_RXBuffer){ int type=USB_RXBuffer[2]; MESSAGES ms=MESSAGES.values()[type]; switch(ms) { case READ_PARAMETER_VALUE: // read parameter values switch(prm){ case PARAMETER_DRIVE_MODE: // paramet drive mode Helper.paramDriveMod =(Integer.toString(((USB_RXBuffer[4]<< 8)&0xff00))); System.out.println(Helper.paramDriveMod+"drive mode is selectd ");//here it shows the value that I need. ..........}}//let say end switch and method and the following is an third class method use the above class method public void buttonSwitch(int value) throws InterruptedException{ boolean bool=true; int c=0; int delay=(int) Math.random(); while(bool){ int param=3; PARAMETERS prm=PARAMETERS.values()[param]; switch(value){ case 0: value=1; while(c<5){ Thread.sleep(delay); protocol.onSending(3,prm.PARAMETER_DRIVE_MODE.ordinal(),dataToRead,dataToRead.length);//read drive mode System.out.println(Helper.paramDriveMod+" drive mode is ..........in wile loop");//here it shows null value }}//let say end switch and method what is the reason that this variable lose its value?

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  • How to Set up Virtual Static Subdomain

    - by Chip D
    Given current rewrite rules at http://www.example.com/: Options +FollowSymlinks +Includes RewriteEngine on RewriteBase / RewriteCond %{HTTP_HOST} !^www\.example\.com [NC] RewriteCond %{HTTP_HOST} !^$ RewriteRule ^/?(.*) http://www.example.com/$1 [L,R,NE] # Remove all "index.html"s. RewriteCond %{THE_REQUEST} \ /(.+/)?index\.html(\?.*)?\ [NC] RewriteRule ^(.+/)?index\.html$ /%1 [R=301,L] # Remove all "index.php"s. RewriteCond %{THE_REQUEST} \ /(.+/)?index\.php(\?.*)?\ [NC] RewriteRule ^(.+/)?index\.php$ /%1 [R=301,L] I'm attempting to serve some site assets (.png|.ico|.jpg|.gif|.css|.js) from a static subdomain like http://static.example.com which my Apache 1.3 shared host (GoDaddy) has mapped to a subdirectory for file management (http://www.example.com/static/). Currently these assets live in same-site subdirectories such as images/, js/, css/, etc. (1) Something...maybe the "+www" rewrite rule?...is not letting me access the subdomain. Is this likely caused by my rewrite rules above, or do I need to set up DNS changes with the host to enable access to the subdirectory, in addition to changing the rewrite rules? (2) Do I have to move those assets to that subdirectory and change all references sitewide? Would that perform the fastest? (3) Or can .htaccess make this much easier? (4) Should my first rewrite rule above include L,R=301,NE instead of [L,R,NE]?

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  • static member specialization of templated child class and templated base class

    - by b3nj1
    I'm trying to have a templated class (here C) that inherits from another templated class (here A) and perform static member specialization (of int var here), but I cant get the right syntax to do so (if it's possible #include <iostream> template<typename derived> class A { public: static int var; }; //This one works fine class B :public A<B> { public: B() { std::cout << var << std::endl; } }; template<> int A<B>::var = 9; //This one doesn't works template<typename type> class C :public A<C<type> > { public: C() { std::cout << var << std::endl; } }; //template<> template<typename type> int A<C<type> >::a = 10; int main() { B b; C<int> c; return 0; } I put an example that works with a non templated class (here B) and i can get the static member specialization of var, but for C that just doesn't work. Here is what gcc tells me : test.cpp: In constructor ‘C<type>::C()’: test.cpp:29:26: error: ‘var’ was not declared in this scope test.cpp: At global scope: test.cpp:34:18: error: template definition of non-template ‘int A<C<type> >::a’ I'm using gcc version 4.6.3, thanks for any help

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  • XCode vs VS2008 or how to work with a static library project on XCode

    - by VansFannel
    Hello. I've working with Visual Studio for a long time and now I'm working with XCode. On Visual Studio I can work with more than one project at the same time adding them to a solution (imagine a solutin with a windows application project and a library project). Now I have XCode and two projects: an iPhone application and a static library. Is there something similar to Visual Studio's solution on XCode? If the answer is not, how can I link my iPhone application with the static library? Thank you.

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  • Should static analysis warnings fail the CI build?

    - by Cara
    Our team is investigating various options for static analysis in our project, and have mixed opinions about whether we want our Continuous Integration build to fail because of warnings from static analysis. The argument against failing the build is that there are often exceptions to the rules, and attempting to work around them just to make the build succeed reduces productivity. A better approach would be to generate reports with the build, and regularly dedicate developer time to addressing the reported issues. The counter-argument is that it is easy for the technical debt to build up if the bugs are not addressed immediately. Also, if the build fails when a potential bug is introduced, the amount of time required to fix it is reduced. What are your thoughts?

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  • Weak-linking with static libraries

    - by Jaakko L.
    I have declared an external function with a GCC weak attribute in a .c file: extern int weakFunction( ) __attribute__ ((weak)); Compiled object file has weakFunction defined as a weak symbol. Output of nm: 1791: w weakFunction I am calling the weak defined function as follows: if (weakFunction != NULL) { weakFunction(); } When I link the program by defining the object files as parameters to GCC (gcc main.o weakf.o -o main.exe) weak symbols work fine. If I leave the weakf.o out of linking, the function address is NULL in main.c and the function won't be called. Problem is, when weakf.o is inside a static library, for some reason the linker doesn't find the function and the function address always ends up being NULL. Static library is created with ar: ar rcs weaklibrary weakf.o Anyone had similar problems?

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  • Memory allocation in case of static variables

    - by eSKay
    I am always confused about static variables, and the way memory allocation happens for them. For example: int a = 1; const int b = 2; static const int c = 3; int foo(int &arg){ arg++; return arg; } How is the memory allocated for a,b and c? What is the difference (in terms of memory) if I call foo(a), foo(b) and foo(c)?

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  • Hybrid static/dynamic Google Map

    - by jonathanconway
    Ever noticed that when you go to maps.google.com and do a search (say, car wash), it renders a lot of results (represented by small circles) and a few prominent ones (seen as regular-size pins)? Notice how quickly it does this? From what I can tell from analyzing this in Firebug, much of this is generated on the server and sent to the client as a static image. However, it's still dynamic. You can still zoom in and out, or click on a result and see a dynamic InfoWindow rendered. Google have made the map quick and smooth using static images, while still making it flexible. Is there a way to do this kind of 'pre-loading' with my own Google Map (implemented with the Google Maps API)?

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  • Static compilation in the .NET world

    - by AngryHacker
    I'll be writing a small desktop app for a client that has WinXP machines and they won't be installing the .NET framework (at least not for me). So my choices are limited to either C++ or VB6, neither of which sound great. I remember reading back in the day that Mono came up with a static compiler, but recently the only thing I could find is Miguel de Icaza's entry on static compilation for a game engine for the purposes of running the app on the iPhone - not what I had in mind. Are there any products out there, free or commercial that will allow me to statically compile my .net 3.5 winform app? Thanks

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  • Static Function Help C++

    - by Alex
    I can't get past this issue I am having. Here's a simple example: class x { public: void function(void); private: static void function2(void); void x::function(void) { x::function2(void); } static void function2(void) { //something } } I get errors in which complain about function2 being private. If I make it public (which I don't really want to do) I get errors about an undefined reference to function2. What am I doing wrong? Thank you!

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  • A function's static and dynamic parent

    - by legends2k
    I'm reading Thinking in C++ (vol. 2): Whenever a function is called, information about that function is pushed onto the runtime stack in an activation record instance (ARI), also called a stack frame. A typical stack frame contains (1) the address of the calling function (so execution can return to it), (2) a pointer to the ARI of the function’s static parent (the scope that lexically contains the called function, so variables global to the function can be accessed), and (3) a pointer to the function that called it (its dynamic parent). The path that logically results from repetitively following the dynamic parent links is the dynamic chain, or call chain I'm unable to comprehend what the author means as function's static and dynamic parent. Also am not able to differentiate between item 1, 2 or 3. They all seem to be the same. Can someone please explain this passage to me?

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  • Static Member Variables of the Same Class in C++

    - by helixed
    I'm trying to create a class which contains a static pointer to an instance of itself. Here's an example: A.h: #include <iostream> #ifndef _A_H #define _A_H class A { static A * a; }; A * a = NULL; #endif However, when I include A.h in another file, such as: #include "A.h" class B { }; I get the following error: ld: duplicate symbol _a in /Users/helixed/Desktop/Example/build/Example.build/Debug/Example.build/Objects-normal/x86_64/B.o and /Users/helixed/Desktop/Example/build/Example.build/Debug/Examplebuild/Objects-normal/x86_64/A.o I'm using the Xcode default compiler on Mac OS X Snow Leopard. Thanks, helixed

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  • Static string variable in Objective C on iphone

    - by Prajakta
    Hi, How to create & access static string in iPhone (objective c)? I declare static NSString *str = @"OldValue" in class A. If i assign some value to this in class B as str = @"NewValue". This value persists for all methods in class B. But if I access it in class C (after assignment in B) I am getting it as OldValue. Am I missing something? Should i use extern in other classes? Thanks & Regards, Yogini

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  • Static Access To Multiple Instance Variable

    - by Qua
    I have a singleton instance that is referenced throughout the project which works like a charm. It saves me the trouble from having to pass around an instance of the object to every little class in the project. However, now I need to manage multiple instances of the previous setup, which means that the singleton pattern breaks since each instance would need it's own singleton instance. What options are there to still maintain static access to the singleton? To be more specific, we have our game engine and several components and plugins reference the engine through a static property. Now our server needs to host multiple game instances each having their own engine, which means that on the server side the singleton pattern breaks. I'm trying to avoid all the classes having the engine in the constructor.

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