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  • C++, create an instance from a static method

    - by Manux
    Hello, let's say I want my users to use only one class, say SpecialData. Now, this data class would have many methods, and depending on the type of data, the methods do different things, internally, but return externally similar results. Therefore my wanting to have one "public" class and other "private", child classes that would change the behavior of methods, etc... It would be amazingly more simple for some types of data that need to be built to do something like this: SpecialData& sm = SpecialData::new_supermatrix(); and new_supermatrix() would return a SuperMatrix instance, which inherits from most behaviors of SpecialData. my header: static SpecialData& new_supermatrix(); my cpp: SpecialData& SpecialData::new_supermatrix()(){ return SuperMatrix(MATRIX_DEFAULT_MAGNITUDE,1000,1239,FLOAT32,etc...); } The problem is, I get this error, which is probably logical due to the circumstances: invalid initialization of non-const reference of type ‘SpecialData&’ from a temporary of type ‘SpecialData’ So, any ideas?

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  • static images aren't caching with php-generated page

    - by scootklein
    Our website was just converted to being generated by mod_rewrite and php scripts. Images aren't caching in browsers when they seemingly should be. All images follow format: <img src="/images/header.png" /> I must avoid the script completely caching because the PHP parser needs to handle each page dynamically on each request; however, the download overhead of the large images is cumbersome on every single page load. I would ideally provide headers for "Cache-Control: no-cache, must-revalidate" and "Expires: some_date_in_the_past" to force revalidation of the PHP script. Why isn't the browser caching static images with consistent href values across all pages?

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  • Xcode debugger showing assembler for nested classes in a static library

    - by Massif
    I have a project A which creates a static library. I have a project B which uses this library. When I am debugging project B, certain functions within project A will display assembler when stepped into or when a breakpoint set inside them is hit. In the debug navigator, the line containing the function is grey instead of black. The strange part is that other functions in the same source file have no problems displaying. The thing that all these functions seem to have in common is that they belong to nested classes. However, I'm not totally convinced that this is the issue since functions from other nested classes display correctly. Does anyone know the cause of this?

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  • Static constructor can run after the non-static constructor. Is this a compiler bug?

    - by Joe H
    The output from the following program is: Non-Static Static Non-Static Is this a compiler bug? I expected: Static Non-Static Non-Static because I thought the static constructor was ALWAYS called before the non-static constructor. I tested this with Visual Studio 2010 using both .net 3.5 and .net 4.0. using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace StaticConstructorBug { class Program { static void Main(string[] args) { var mc = new MyClass(); Console.ReadKey(); } } public class MyClass { public MyClass() { Console.WriteLine("Non-static"); } static MyClass() { Console.WriteLine("Static"); } public static MyClass aVar = new MyClass(); } }

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  • Static methods requiring var

    - by Charlie Pigarelli
    Ok, i'm stuck on this, why don't i get what i need? class config { private $config; # Load configurations public function __construct() { loadConfig('site'); // load a file with $cf in it loadConfig('database'); // load another file with $cf in it $this->config = $cf; // $cf is an array unset($cf); } # Get a configuration public static function get($tag, $name) { return $this->config[$tag][$name]; } } I'm getting this: Fatal error: Using $this when not in object context in [this file] on line 22 [return $this->config[$tag][$name];] And i need to call the method in this way: config::get()...

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  • iPhone SDK linking errors with static library

    - by Nico
    Hello all! I've built my own static library with components to be reused in my project, and recently had the need to update a bunch of classes. Specifically, some methods' signatures were changed due to the fact that some classes changed names. What happens now is that the library compiles fine on its own, but, when added to an app project, the project fails to link: Ld build/Sucursales.build/Debug-iphoneos/Sucursales.build/Objects-normal/armv6/Sucursales normal armv6 cd /Users/nameghino/src/Sucursales setenv IPHONEOS_DEPLOYMENT_TARGET 3.1 setenv PATH "/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin:/Developer/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin" /Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/gcc-4.2 -arch armv6 -isysroot /Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS3.2.sdk -L/Users/nameghino/src/Sucursales/build/Debug-iphoneos -L/Users/nameghino/src/Sucursales/../../Library/MyLibraries/MSSharedLibrary-1.0.0 -F/Users/nameghino/src/Sucursales/build/Debug-iphoneos -filelist /Users/nameghino/src/Sucursales/build/Sucursales.build/Debug-iphoneos/Sucursales.build/Objects-normal/armv6/Sucursales.LinkFileList -dead_strip -lxml2 -ObjC -all_load -miphoneos-version-min=3.1 -framework Foundation -framework UIKit -framework CoreGraphics -lsqlite3.0 -framework CoreLocation -framework MapKit -lxml2 /Users/nameghino/src/MSSharedComponents/Frameworks/MSSharedLibrary/build/Debug-iphoneos/libMSSharedLibrary.a -o /Users/nameghino/src/Sucursales/build/Sucursales.build/Debug-iphoneos/Sucursales.build/Objects-normal/armv6/Sucursales Undefined symbols: "_OBJC_CLASS_$_DataCatalogService_GetSingleRow", referenced from: objc-class-ref-to-DataCatalogService_GetSingleRow in libMSSharedLibrary.a(MSDataCatalogSpecification.o) **"_OBJC_CLASS_$_DataCatalogService_ArrayOfString", referenced from: objc-class-ref-to-DataCatalogService_ArrayOfString in libMSSharedLibrary.a(MSDataCatalogSpecification.o) "_OBJC_CLASS_$_DataCatalogService_GetSingleRowResponse", referenced from: objc-class-ref-to-DataCatalogService_GetSingleRowResponse in libMSSharedLibrary.a(MSSingleRowResultsParser.o) "_OBJC_CLASS_$_DataCatalogService_GetMultiRowResponse", referenced from: objc-class-ref-to-DataCatalogService_GetMultiRowResponse in libMSSharedLibrary.a(MSMultiRowResultsParser.o) "_OBJC_CLASS_$_DataCatalogService_GetMultiRow", referenced from: objc-class-ref-to-DataCatalogService_GetMultiRow in libMSSharedLibrary.a(MSDataCatalogSpecification.o) "_OBJC_CLASS_$_DataCatalogService_HelloWorldResponse", referenced from: objc-class-ref-to-DataCatalogService_HelloWorldResponse in libMSSharedLibrary.a(DataCatalogService.o) ld: symbol(s) not found collect2: ld returned 1 exit status** The curious thing is that after a lot of project cleanups (both in the app and the lib projects), I still get the same issue. Even after starting a new project, the problem is still there. I've also taken care to restart Xcode between a clean and a build a couple of times, but no good. Any ideas on where to look? Thanks in advance Nico

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  • Static libpng link with visual studio 2010

    - by Sanctus2099
    Hey guys. I'm trying to add PNG support to my application and thus I want to include libpng. I know it needs zlib and thus I downloaded that as well. I went into the png folder/projects/vstudio and I opened the solution. I compiled it and it went just fine. I added some headers from it into my application and I copied the lib files. My program is a dll written in c++ which is later used from C#. When I run it in C# it complains about not finding my dll (tough if I remove the png part it works fine). I've had this problem before and it usually means a dll dependency is wrong. Now... libpng compiled both some .lib files and some .dll files. The dll files are bigger. My only guess is that it needs the dll files as well but I've seen that people can link to libpng without a dll. So my questions is: How can I compile libpng(and zlib for that instance) into just static libraries and how can I include those in my projects? I've searched around the internet and I couldn't find anything useful.

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  • Simulating aspects of static-typing in a duck-typed language

    - by Mike
    In my current job I'm building a suite of Perl scripts that depend heavily on objects. (using Perl's bless() on a Hash to get as close to OO as possible) Now, for lack of a better way of putting this, most programmers at my company aren't very smart. Worse, they don't like reading documentation and seem to have a problem understanding other people's code. Cowboy coding is the game here. Whenever they encounter a problem and try to fix it, they come up with a horrendous solution that actually solves nothing and usually makes it worse. This results in me, frankly, not trusting them with code written in duck typed language. As an example, I see too many problems with them not getting an explicit error for misusing objects. For instance, if type A has member foo, and they do something like, instance->goo, they aren't going to see the problem immediately. It will return a null/undefined value, and they will probably waste an hour finding the cause. Then end up changing something else because they didn't properly identify the original problem. So I'm brainstorming for a way to keep my scripting language (its rapid development is an advantage) but give an explicit error message when an an object isn't used properly. I realize that since there isn't a compile stage or static typing, the error will have to be at run time. I'm fine with this, so long as the user gets a very explicit notice saying "this object doesn't have X" As part of my solution, I don't want it to be required that they check if a method/variable exists before trying to use it. Even though my work is in Perl, I think this can be language agnostic.

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  • Assigning static final int in a JUnit (4.8.1) test suite

    - by Dr. Monkey
    I have a JUnit test class in which I have several static final ints that can be redefined at the top of the tester code to allow some variation in the test values. I have logic in my @BeforeClass method to ensure that the developer has entered values that won't break my tests. I would like to improve variation further by allowing these ints to be set to (sensible) random values in the @BeforeClass method if the developer sets a boolean useRandomValues = true;. I could simply remove the final keyword to allow the random values to overwrite the initialisation values, but I have final there to ensure that these values are not inadvertently changed, as some tests rely on the consistency of these values. Can I use a constructor in a JUnit test class? Eclipse starts putting red underlines everywhere if I try to make my @BeforeClass into a constructor for the test class, and making a separate constructor doesn't seem to allow assignment to these variables (even if I leave them unassigned at their declaration); Is there another way to ensure that any attempt to change these variables after the @BeforeClass method will result in a compile-time error? Can I make something final after it has been initialised?

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  • iPhone static library Clang/LLVM error: non_lazy_symbol_pointers

    - by Bekenn
    After several hours of experimentation, I've managed to reduce the problem to the following example (C++): extern "C" void foo(); struct test { ~test() { } }; void doTest() { test t; // 1 foo(); // 2 } This is being compiled for iOS devices in XCode 4.2, using the provided Clang compiler (Apple LLVM compiler 3.0) and the iOS 5.0 SDK. The project is configured as a Cocoa Touch Static Library, and "Enable Linking With Shared Libraries" is set to No because I'm building an AIR native extension. The function foo is defined in another external library. (In my actual project, this would be any of the C API functions defined by Adobe for use in AIR native extensions.) When attempting to compile this code, I get back the error: FATAL:incompatible feature used: section type non_lazy_symbol_pointers (must specify "-dynamic" to be used) clang: error: assembler command failed with exit code 1 (use -v to see invocation) The error goes away if I comment out either of the lines marked 1 or 2 above, or if I change the build setting "Enable Linking With Shared Libraries" to Yes. (However, if I change the build setting, then I get multiple ld warning: unexpected srelocation type 9 warnings when linking the library into the final project, and the application crashes when running on the device.) The build error also goes away if I remove the destructor from test. So: Is this a bug in Clang? Am I missing some all-important and undocumented build setting? The interaction between an externally-provided function and a struct with a destructor is very peculiar, to say the least.

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  • Getting the name of a child class in the parent class (static context)

    - by Benoit Myard
    Hi everybody, I'm building an ORM library with reuse and simplicity in mind; everything goes fine except that I got stuck by a stupid inheritance limitation. Please consider the code below: class BaseModel { /* * Return an instance of a Model from the database. */ static public function get (/* varargs */) { // 1. Notice we want an instance of User $class = get_class(parent); // value: bool(false) $class = get_class(self); // value: bool(false) $class = get_class(); // value: string(9) "BaseModel" $class = __CLASS__; // value: string(9) "BaseModel" // 2. Query the database with id $row = get_row_from_db_as_array(func_get_args()); // 3. Return the filled instance $obj = new $class(); $obj->data = $row; return $obj; } } class User extends BaseModel { protected $table = 'users'; protected $fields = array('id', 'name'); protected $primary_keys = array('id'); } class Section extends BaseModel { // [...] } $my_user = User::get(3); $my_user->name = 'Jean'; $other_user = User::get(24); $other_user->name = 'Paul'; $my_user->save(); $other_user->save(); $my_section = Section::get('apropos'); $my_section->delete(); Obviously, this is not the behavior I was expecting (although the actual behavior also makes sense).. So my question is if you guys know of a mean to get, in the parent class, the name of child class.

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  • How can I get a static URL to a map image using the Google Static Maps API?

    - by Argote
    === BACKGROUND === Hello, so I've published a Web-App (still in "Beta") which uses the Flickr API to get information for the photos of a particular Flickr user and generates IPB code to post any of his/her images. While Flickr now gives you the IPB code to show the image and link back to the photo site directly on its site, my App also has the option of embeding the title, description, select EXIF data, location information, etc. into the post for the IPB forum. === PROBLEM === I've most recently added the option to integrate a Google Maps image of the photo's geolocation data into the post by using the Google Static Maps API. The problem is that the image URL I have is in the following form (including IPB [IMG] tags): [IMG]http://maps.google.com/maps/api/staticmap?zoom=16&size=600x600&maptype=hybrid&markers=19.387687,-99.251732&sensor=false[/IMG] Which shows this example image (In practice the image size is user selectable): However, some IPB forums seem to not support dyamic image URLs which gives me a broken image, I'd like to replace the [IMG]http://maps.google.com/maps/api/staticmap?zoom=16&size=600x600&maptype=hybrid&markers=19.387687,-99.251732&sensor=false[/IMG] with something like [IMG]http://maps.google.com/maps/api/staticmap/map0000001.png[/IMG] which should be supported by all IPB forums. Thanks in advance for your help. In case you're interested, the most recent "released" version of my Web-App can be found here: http://flickr.argote.mx/ (The changes I mention here are still on local development server).

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  • NPE annotation scenarios and static-analysis tools for Java

    - by alex2k8
    Here is a number of code snippets that can throw NullPointerException. 01: public void m1(@Nullable String text) { System.out.print(text.toLowerCase()); // <-- expect to be reported. } 02: private boolean _closed = false; public void m1(@Nullable String text) { if(_closed) return; System.out.print(text.toLowerCase()); // <-- expect to be reported. } 03: public void m1(@NotNull String text) { System.out.print(text.toLowerCase()); } public @Nullable String getText() { return "Some text"; } public void m2() { m1(getText()); // <-- expect to be reported. } Different people have access to different static-analysis tools. It would be nice to collect information, what tools are able to detect and report the issues, and what are failing. Also, if you have your own scenarious, please, publish them. Here my results FindBugs (1.3.9): 01: Parameter must be nonnull but is marked as nullable 02: NOT reported 03: NOT reported IntelliJ IDE 9.0.2 (Community edition): 01: Method invocation text.toLowerCase() may produce java.lang.NullPointerException 02: Method invocation text.toLowerCase() may produce java.lang.NullPointerException 03: Argument getText() might be null

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  • Django choking oddly on some static media

    - by Edan Maor
    My situation: I'm serving static media via Django on my dev machine. On some files that I try and load, I get back this error: Traceback: File "c:\Program Files\Python26\Lib\site-packages\django\core\handlers\base.py" in get_response 92. response = callback(request, *callback_args, **callback_kwargs) File "E:\Stack2Blog\src.hg\stack2blog\..\stack2blog\stack2blogapp\views.py" in userpage 71. so_user = site.user(userid) File "E:\Stack2Blog\src.hg\stack2blog\..\stack2blog\stack2blogapp\stackexchange.py" in user 476. u, = self.users((nid,), **kw) File "E:\Stack2Blog\src.hg\stack2blog\..\stack2blog\stack2blogapp\stackexchange.py" in users 481. return self._get(User, ids, 'users', kw) File "E:\Stack2Blog\src.hg\stack2blog\..\stack2blog\stack2blogapp\stackexchange.py" in _get 471. return self.build(root, typ, coll, kw) File "E:\Stack2Blog\src.hg\stack2blog\..\stack2blog\stack2blogapp\stackexchange.py" in build 448. json = self._request(url, kw) File "E:\Stack2Blog\src.hg\stack2blog\..\stack2blog\stack2blogapp\stackexchange.py" in _request 422. dump = json.load(data) File "c:\Program Files\Python26\lib\json\__init__.py" in load 264. return loads(fp.read(), Exception Type: AttributeError at /userpage/362498 Exception Value: 'str' object has no attribute 'read' I've traced it to specific files which don't work (by going to their specific urls). Here's the odd part: changing the filename of the files makes them suddenly work. For example, I had a file called 'post.jpg', which gave this error. I renamed it to 'pos.jpg' and it worked. Back to 'post.jpg' and it gives the same error.

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  • Care to be taken when serving static content (JS, CSS, Media) from different domain?

    - by Aahan Krish
    Let me try to explain by example. Say website is hosted at example.com (NOT www.example.com). In order to serve static content cookie-free, I've chosen to use a different domain example-static.com. Now, lets consider that my static content is currently served like this: http://example.com/js/script.js http://example.com/css/style.css http://example.com/media/image.jpg ** Now I create a CNAME record aliasing example-static.com to my main domain i.e. example.com so that the static content is served as such: http://example-static.com/js/script.js http://example-static.com/css/style.css http://example-static.com/media/image.jpg ** Is that all I have to do? Will all browsers execute JavaScript files and load web fonts without any security concerns? OR should I be using some .htaccess rules to modify header information and the like? PS: It would be great if you can provide what rules should be added, if need be.

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  • Lightweight HTTP application/server for static content

    - by PartlyCloudy
    Hi, I am in need of a scalable and performant HTTP application/server that will be used for static file serving/uploading. So I only need support for GET and PUT operations. However, there are a few extra features that I need: Custom authentication: I need to check credentials against a database for each request. Thus I must be able to integrate propietary database interaction. Support for signed access keys: The access to resources via PUT should be signed using a key like http://uri/?key=foo The key then contains information about the request like md5(user + path + secret) which allows me to block unwanted requests. The application/server should allow me to check for this. Performance: I'd like to avoid piping content as much as possible. Otherwise the whole application could be implemented in Perl/etc. in a few lines as CGI. Perlbal (in webserver mode) looks nice, however the single-threaded model does not fit with my database lookup and it does also not support query strings. Lighttp/Nginx/… have some modules for these tasks, however it is not feasible putting everything together without ending up writing own extensions/modules. So how would you solve this? Are there other leightweight webservers available for this? Should I implement an application inside of a webserver (i.e. CGI). How can I avoid/speed up piping content between the webserver and my application. Thanks in advance!

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  • Static libraries in version-cross-compiled program

    - by Brian Postow
    I have a unix command line app (with big nasty makefile) that I'm trying to run on a mac. I am compiling it on a 10.6 system, with all of the appropriate libraries of course. The deployment environment is a 10.5 system, with no extra libraries. I compiled without -dynamic, and it appears to have static libraries, correctly. When I run it on the 10.6 system, it works. However, when I run it on the 10.5 system, I get: dyld: unknown required load command 0x80000022 I got this same error when I compiled things for the 10.6 system using the 10.5 xcode, so it looks like a version mis-match type problem. However, I used gcc-4.0, and $CFLAGS = -isysroot /Developer/SDKs/MacOSX10.5.sdk -mmacosx-version-min=10.5 so it SHOULD be set up for 10.5... any ideas? thanks Editing an ancient question: I have the exact same problem on a different computer. This time I am at 10.5.8, fully update, the same executable works on 10.6 still. Has anyone had any luck with this in the months since I asked this?

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  • C++ private inheritance and static members/types

    - by WearyMonkey
    I am trying to stop a class from being able to convert its 'this' pointer into a pointer of one of its interfaces. I do this by using private inheritance via a middle proxy class. The problem is that I find private inheritance makes all public static members and types of the base class inaccessible to all classes under the inheriting class in the hierarchy. class Base { public: enum Enum { value }; }; class Middle : private Base { }; class Child : public Middle { public: void Method() { Base::Enum e = Base::value; // doesn't compile BAD! Base* base = this; // doesn't compile GOOD! } }; I've tried this in both VS2008 (the required version) and VS2010, neither work. Can anyone think of a workaround? Or a different approach to stopping the conversion? Also I am curios of the behavior, is it just a side effect of the compiler implementation, or is it by design? If by design, then why? I always thought of private inheritance to mean that nobody knows Middle inherits from Base. However, the exhibited behavior implies private inheritance means a lot more than that, in-fact Child has less access to Base than any namespace not in the class hierarchy!

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  • How to use external static files with Django (serving external files once again)?

    - by Tomas Novotny
    Hi, even after Googling and reading all relevant posts at StackOverflow, I still can't get static files working in my Django application. Here is how my files look: settings.py MEDIA_ROOT = os.path.join(SITE_ROOT, 'static') MEDIA_URL = '/static/' urs.py from DjangoBandCreatorSite.settings import DEBUG if DEBUG: urlpatterns += patterns('', ( r'^static/(?P<path>.*)$', 'django.views.static.serve', {'document_root': 'static'} )) template: <script type="text/javascript" src="/static/jquery.js"></script> <script type="text/javascript"> I am trying to use jquery.js stored in directory "static". I am using: Windows XP Python 2.6.4 Django 1.2.3 Thank you very much for any help

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  • Delphi static method of a class returning property value

    - by mitko.berbatov
    I'm making a Delphi VCL application. There is a class TStudent where I have two static functions: one which returns last name from an array of TStudent and another one which returns the first name of the student. Their code is something like: class function TStudent.FirstNameOf(aLastName: string): string; var i : integer; begin for i := 0 to Length(studentsArray) - 1 do begin if studentsArray[i].LastName = aLastName then begin result := studentsArray[i].FirstName; Exit; end; end; result := 'no match was found'; end; class function TStudent.LastNameOf(aFirstName: string): string; var i : integer; begin for i := 0 to Length(studentsArray) - 1 do begin if studentsArray[i].FirstName = aFirstName then begin result := studentsArray[i].LastName; Exit; end; end; result := 'no match was found'; end; My question is how can I avoid writing almost same code twice. Is there any way to pass the property as parameter of the functions.

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  • Reflection and the params Keyword

    - by Robert May
    I’ve had to look this up a couple of times, and there’s not much out there, so I end up guessing the same answer over and over. When using MethodBase.GetParameters() to get an array of ParameterInfo object, I often want to get a count of the number of parameters that are out, optional, params, etc.  For out and optional, you can simply check ParameterInfo.IsOut or ParameterInfo.IsOptional or any number of other “Attributes”. However, for params, there isn’t a property on ParameterInfo.  Instead, you have to do this: info.GetCustomAttributes(typeof(ParamArrayAttribute), true) This will get you a set of all of the attributes that are the ParamArrayAttribute, which you can then turn into a linq statement that looks like this: methodParameters.Count(info => info.GetCustomAttributes(typeof(ParamArrayAttribute), true).Count() > 0); Which, assuming that methodParameters is the result of MethodBase.GetParameters, will give you a count of the number of parameters that have the params keyword.  Of course, there can be only one, but who’s counting! Now, hopefully, the next time I try to look this up, my own blog will get the values. Technorati Tags: Reflection

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  • Associate "Code/Properties/Stuff" with Fields in C# without reflection. I am too indoctrinated by J

    - by AlexH
    I am building a library to automatically create forms for Objects in the project that I am working on. The codebase is in C#, and essentially we have a HUGE number of different objects to store information about different things. If I send these objects to the client side as JSON, it is easy enough to programatically inspect them to generate a form for all of the properties. The problem is that I want to be able to create a simple way of enforcing permissions and doing validation on the client side. It needs to be done on a field by field level. In javascript I would do this by creating a parallel object structure, which had some sort of { permissions : "someLevel", validator : someFunction } object at the nodes. With empty nodes implying free permissions and universal validation. This would let me simply iterate over the new object and the permissions object, run the check, and deal with the result. Because I am overfamilar with the hammer that is javascript, this is really the only way that I can see to deal with this problem. My first implementation thus uses reflection to let me treat objects as dictionaries, that can be programatically iterated over, and then I just have dictionaries of dictionaries of PermissionRule objects which can be compared with. Very javascripty. Very awkward. Is there some better way that I can do this? Essentially a way to associate a data set with each property, and then iterate over those properties. Or else am I Doing It Wrong?

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  • Java reflection Method invocations yield result faster than Fields?

    - by omerkudat
    I was microbenchmarking some code (please be nice) and came across this puzzle: when reading a field using reflection, invoking the getter Method is faster than reading the Field. Simple test class: private static final class Foo { public Foo(double val) { this.val = val; } public double getVal() { return val; } public final double val; // only public for demo purposes } We have two reflections: Method m = Foo.class.getDeclaredMethod("getVal", null); Field f = Foo.class.getDeclaredField("val"); Now I call the two reflections in a loop, invoke on the Method, and get on the Field. A first run is done to warm up the VM, a second run is done with 10M iterations. The Method invocation is consistently 30% faster, but why? Note that getDeclaredMethod and getDeclaredField are not called in the loop. They are called once and executed on the same object in the loop. I also tried some minor variations: made the field non-final, transitive, non-public, etc. All of these combinations resulted in statistically similar performance. Edit: This is on WinXP, Intel Core2 Duo, Sun JavaSE build 1.6.0_16-b01, running under jUnit4 and Eclipse.

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  • OpenCV compliation on linux: how to feed to it specific zlib lib?

    - by myWallJSON
    I want to compile OpenCV with same zlib as I use for compilation of Boost Iostreams (not system default one). I want to compile OpenCV as static lib, having zlib compiled as static lib. Currently I use something like : ../$CMAKE_PATH -DCMAKE_INSTALL_PREFIX=./$OPENCV_INSTALL_SUBDIR -DBUILD_WITH_STATIC_CRT=ON -DBUILD_SHARED_LIBS=OFF -DBUILD_PYTHON_SUPPORT=OFF -DOPENCV_EXTRA_C_FLAGS=-fPIC -DOPENCV_BUILD_3RDPARTY_LIBS=TRUE make make install echo Done! I wonder: having some $ZLIB_HEADERS and $ZLIB_LIB_FILES_FOLDER path strings how to feed them into cmake to get OpenCV compiled with built by me zlib?

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  • How to use reflection to get a default constructor?

    - by Qwertie
    I am writing a library that generates derived classes of abstract classes dynamically at runtime. The constructor of the derived class needs a MethodInfo of the base class constructor so that it can invoke it. However, for some reason Type.GetConstructor() returns null. For example: abstract class Test { public abstract void F(); } public static void Main(string[] args) { ConstructorInfo constructor = typeof(Test).GetConstructor( BindingFlags.NonPublic | BindingFlags.Public, null, System.Type.EmptyTypes, null); // returns null! } Note that GetConstructor returns null even if I explicitly declare a constructor in Test, and even if Test is not abstract.

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