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  • Python: How do I create a reference to a reference?

    - by KCArpe
    Hi, I am traditionally a Perl and C++ programmer, so apologies in advance if I am misunderstanding something trivial about Python! I would like to create a reference to a reference. Huh? Ok. All objects in Python are actually references to the real object. So, how do I create a reference to this reference? Why do I need/want this? I am overriding sys.stdout and sys.stderr to create a logging library. I would like a (second-level) reference to sys.stdout. If I could create a reference to a reference, then I could create a generic logger class where the init function receives a reference to a file handle reference that will be overrided, e.g., sys.stdout or sys.stderr. Currently, I must hard-code both values. Cheers, Kevin

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  • excplicitly casting constness in

    - by jimifiki
    With the following code void TestF(const double ** testv){;} void callTest(){ double** test; TestF(test); } I get this: error C2664: 'TestF' : cannot convert parameter 1 from 'double **' to 'const double **' I cannot understand why. Why test cannot be silently casted to const double**? Why should I do it explicitly? I know that TestF(const_cast<const double**>(test)) makes my code correct, but I feel this should be unnecessary. Are there some key concepts about const that I'm missing?

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  • Can you pass by reference in Java?

    - by dbones
    Hi. Sorry if this sounds like a newbie question, but the other day a Java developer mentioned about passing a paramter by reference (by which it was ment just pass a Reference object) From a C# perspective I can pass a reference type by value or by reference, this is also true to value types I have written a noddie console application to show what i mean.. can i do this in Java? namespace ByRefByVal { class Program { static void Main(string[] args) { //Creating of the object Person p1 = new Person(); p1.Name = "Dave"; PrintIfObjectIsNull(p1); //should not be null //A copy of the Reference is made and sent to the method PrintUserNameByValue(p1); PrintIfObjectIsNull(p1); //the actual reference is passed to the method PrintUserNameByRef(ref p1); //<-- I know im passing the Reference PrintIfObjectIsNull(p1); Console.ReadLine(); } private static void PrintIfObjectIsNull(Object o) { if (o == null) { Console.WriteLine("object is null"); } else { Console.WriteLine("object still references something"); } } /// <summary> /// this takes in a Reference type of Person, by value /// </summary> /// <param name="person"></param> private static void PrintUserNameByValue(Person person) { Console.WriteLine(person.Name); person = null; //<- this cannot affect the orginal reference, as it was passed in by value. } /// <summary> /// this takes in a Reference type of Person, by reference /// </summary> /// <param name="person"></param> private static void PrintUserNameByRef(ref Person person) { Console.WriteLine(person.Name); person = null; //this has access to the orginonal reference, allowing us to alter it, either make it point to a different object or to nothing. } } class Person { public string Name { get; set; } } } If it java cannot do this, then its just passing a reference type by value? (is that fair to say) Many thanks Bones

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  • Difference between static const char* and const char*.

    - by Will MacDonagh
    Could someone please explain the difference in how the 2 snippets of code are handled below? They definitely compile to different assembly code, but I'm trying to understand how the code might act differently. I understand that string literals are thrown into read only memory and are effectively static, but how does that differ from the explicit static below? struct Obj1 { void Foo() { const char* str( "hello" ); } }; and struct Obj2 { void Bar() { static const char* str( "hello" ); } };

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  • pure/const functions in C++

    - by Albert
    Hi, I'm thinking of using pure/const functions more heavily in my C++ code. (pure/const attribute in GCC) However, I am curious how strict I should be about it and what could possibly break. The most obvious case are debug outputs (in whatever form, could be on cout, in some file or in some custom debug class). I probably will have a lot of functions, which don't have any side effects despite this sort of debug output. No matter if the debug output is made or not, this will absolutely have no effect on the rest of my application. Or another case I'm thinking of is the use of my own SmartPointer class. In debug mode, my SmartPointer class has some global register where it does some extra checks. If I use such an object in a pure/const function, it does have some slight side effects (in the sense that some memory probably will be different) which should not have any real side effects though (in the sense that the behaviour is in any way different). Similar also for mutexes and other stuff. I can think of many complex cases where it has some side effects (in the sense of that some memory will be different, maybe even some threads are created, some filesystem manipulation is made, etc) but has no computational difference (all those side effects could very well be left out and I would even prefer that). How does it work out in practice? If I mark such functions as pure/const, could it break anything (considering that the code is all correct)?

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  • C++ const-reference semantics?

    - by Kristoffer
    Consider the sample application below. It demonstrates what I would call a flawed class design. #include <iostream> using namespace std; struct B { B() : m_value(1) {} long m_value; }; struct A { const B& GetB() const { return m_B; } void Foo(const B &b) { // assert(this != &b); m_B.m_value += b.m_value; m_B.m_value += b.m_value; } protected: B m_B; }; int main(int argc, char* argv[]) { A a; cout << "Original value: " << a.GetB().m_value << endl; cout << "Expected value: 3" << endl; a.Foo(a.GetB()); cout << "Actual value: " << a.GetB().m_value << endl; return 0; } Output: Original value: 1 Expected value: 3 Actual value: 4 Obviously, the programmer is fooled by the constness of b. By mistake b points to this, which yields the undesired behavior. My question: What const-rules should you follow when designing getters/setters? My suggestion: Never return a reference to a member variable if it can be set by reference through a member function. Hence, either return by value or pass parameters by value. (Modern compilers will optimize away the extra copy anyway.)

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  • C++ find method is not const?

    - by Rachel
    I've written a method that I'd like to declare as const, but the compiler complains. I traced through and found that this part of the method was causing the difficulty: bool ClassA::MethodA(int x) { bool y = false; if(find(myList.begin(), myList.end(), x) != myList.end()) { y = true; } return y; } There is more happening in the method than that, but with everything else stripped away, this was the part that didn't allow the method to be const. Why does the stl find algorithm prevent the method from being const? Does it change the list in any way?

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  • STL Static-Const Member Definitions

    - by javery
    How does the following work? #include <limits> int main() { const int* const foo = &std::numeric_limits<int> ::digits; } I was under the impression that in order to take an address of a static const-ant member we had to physically define it in some translation unit in order to please the linker. That said, after looking at the preprocessed code for this TU, I couldn't find an external definition for the digits member (or any other relevant members). I tested this on two compilers (VC++ 10 and g++ 4.2.4) and got identical results (i.e., it works). Does the linker auto-magically link against an object file where this stuff is defined, or am I missing something obvious here?

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  • boost::shared_ptr<const T> to boost::shared_ptr<T>

    - by Flevine
    I want to cast the const-ness out of a boost::shared_ptr, but I boost::const_pointer_cast is not the answer. boost::const_pointer_cast wants a const boost::shared_ptr, not a boost::shared_ptr. Let's forego the obligitory 'you shouldn't be doing that'. I know... but I need to do it... so what's the best/easiest way to do it? For clarity sake: boost::shared_ptr<const T> orig_ptr( new T() ); boost::shared_ptr<T> new_ptr = magic_incantation(orig_ptr); I need to know the magic_incantation() Thanks!

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  • Installing CUDA on Ubuntu 12.04 with nvidia driver 295.59

    - by johnmcd
    I have been trying to get cuda to run on a nvidia gt 650m based laptop. I am running Ubuntu 12.04 with the nvidia 295.59 driver. Also, my laptop uses Optimus so I have install the driver via bumblebee. Bumblebee is not working correctly yet -- however I believe it is possible to install CUDA independently. To install CUDA I have followed the instructions detailed here: How can I get nVidia CUDA or OpenCL working on a laptop with nVidia discrete card/Intel Integrated Graphics? However I am still running into problem building the sdk. I made the changes specified at the above link in common.mk, but I got the following (snippet) from the build process: make[2]: Entering directory `/home/john/NVIDIA_GPU_Computing_SDK/C/src/fluidsGL' /usr/bin/ld: warning: libnvidia-tls.so.302.17, needed by /usr/lib/nvidia-current/libGL.so, not found (try using -rpath or -rpath-link) /usr/bin/ld: warning: libnvidia-glcore.so.302.17, needed by /usr/lib/nvidia-current/libGL.so, not found (try using -rpath or -rpath-link) /usr/lib/nvidia-current/libGL.so: undefined reference to `_nv018tls' /usr/lib/nvidia-current/libGL.so: undefined reference to `_nv012glcore' /usr/lib/nvidia-current/libGL.so: undefined reference to `_nv017glcore' /usr/lib/nvidia-current/libGL.so: undefined reference to `_nv012tls' /usr/lib/nvidia-current/libGL.so: undefined reference to `_nv015tls' /usr/lib/nvidia-current/libGL.so: undefined reference to `_nv019tls' /usr/lib/nvidia-current/libGL.so: undefined reference to `_nv000glcore' /usr/lib/nvidia-current/libGL.so: undefined reference to `_nv017tls' /usr/lib/nvidia-current/libGL.so: undefined reference to `_nv013tls' /usr/lib/nvidia-current/libGL.so: undefined reference to `_nv013glcore' /usr/lib/nvidia-current/libGL.so: undefined reference to `_nv018glcore' /usr/lib/nvidia-current/libGL.so: undefined reference to `_nv022tls' /usr/lib/nvidia-current/libGL.so: undefined reference to `_nv007tls' /usr/lib/nvidia-current/libGL.so: undefined reference to `_nv009tls' /usr/lib/nvidia-current/libGL.so: undefined reference to `_nv020tls' /usr/lib/nvidia-current/libGL.so: undefined reference to `_nv014glcore' /usr/lib/nvidia-current/libGL.so: undefined reference to `_nv015glcore' /usr/lib/nvidia-current/libGL.so: undefined reference to `_nv016tls' /usr/lib/nvidia-current/libGL.so: undefined reference to `_nv001glcore' /usr/lib/nvidia-current/libGL.so: undefined reference to `_nv006tls' /usr/lib/nvidia-current/libGL.so: undefined reference to `_nv021tls' /usr/lib/nvidia-current/libGL.so: undefined reference to `_nv011tls' /usr/lib/nvidia-current/libGL.so: undefined reference to `_nv020glcore' /usr/lib/nvidia-current/libGL.so: undefined reference to `_nv019glcore' /usr/lib/nvidia-current/libGL.so: undefined reference to `_nv002glcore' /usr/lib/nvidia-current/libGL.so: undefined reference to `_nv021glcore' /usr/lib/nvidia-current/libGL.so: undefined reference to `_nv014tls' collect2: ld returned 1 exit status make[2]: *** [../../bin/linux/release/fluidsGL] Error 1 make[2]: Leaving directory `/home/john/NVIDIA_GPU_Computing_SDK/C/src/fluidsGL' make[1]: *** [src/fluidsGL/Makefile.ph_build] Error 2 make[1]: Leaving directory `/home/john/NVIDIA_GPU_Computing_SDK/C' make: *** [all] Error 2 The libraries that ld warns about are on my system and are installed on the system: $ locate libnvidia-tls.so.302.17 libnvidia-glcore.so.302.17 /usr/lib/nvidia-current/libnvidia-glcore.so.302.17 /usr/lib/nvidia-current/libnvidia-tls.so.302.17 /usr/lib/nvidia-current/tls/libnvidia-tls.so.302.17 /usr/lib32/nvidia-current/libnvidia-glcore.so.302.17 /usr/lib32/nvidia-current/libnvidia-tls.so.302.17 /usr/lib32/nvidia-current/tls/libnvidia-tls.so.302.17 however /usr/lib/nvidia-current and /usr/lib32/nvidia-current are not being picked up by ldconfig. I have tried adding them by adding a file to /etc/ld.so.conf.d/ which gets past this error, however now I am getting the following error: make[2]: Entering directory `/home/john/NVIDIA_GPU_Computing_SDK/C/src/deviceQueryDrv' cc1plus: warning: command line option ‘-Wimplicit’ is valid for C/ObjC but not for C++ [enabled by default] obj/x86_64/release/deviceQueryDrv.cpp.o: In function `main': deviceQueryDrv.cpp:(.text.startup+0x5f): undefined reference to `cuInit' deviceQueryDrv.cpp:(.text.startup+0x99): undefined reference to `cuDeviceGetCount' deviceQueryDrv.cpp:(.text.startup+0x10b): undefined reference to `cuDeviceComputeCapability' deviceQueryDrv.cpp:(.text.startup+0x127): undefined reference to `cuDeviceGetName' deviceQueryDrv.cpp:(.text.startup+0x16a): undefined reference to `cuDriverGetVersion' deviceQueryDrv.cpp:(.text.startup+0x1f0): undefined reference to `cuDeviceTotalMem_v2' deviceQueryDrv.cpp:(.text.startup+0x262): undefined reference to `cuDeviceGetAttribute' deviceQueryDrv.cpp:(.text.startup+0x457): undefined reference to `cuDeviceGetAttribute' deviceQueryDrv.cpp:(.text.startup+0x4bc): undefined reference to `cuDeviceGetAttribute' deviceQueryDrv.cpp:(.text.startup+0x502): undefined reference to `cuDeviceGetAttribute' deviceQueryDrv.cpp:(.text.startup+0x533): undefined reference to `cuDeviceGetAttribute' obj/x86_64/release/deviceQueryDrv.cpp.o:deviceQueryDrv.cpp:(.text.startup+0x55e): more undefined references to `cuDeviceGetAttribute' follow collect2: ld returned 1 exit status make[2]: *** [../../bin/linux/release/deviceQueryDrv] Error 1 make[2]: Leaving directory `/home/john/NVIDIA_GPU_Computing_SDK/C/src/deviceQueryDrv' make[1]: *** [src/deviceQueryDrv/Makefile.ph_build] Error 2 make[1]: Leaving directory `/home/john/NVIDIA_GPU_Computing_SDK/C' make: *** [all] Error 2 I would appreciate any help that anyone can provide me with. If I can provide any further information please let me know. Thanks.

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  • .net web service: Can't add service reference, only web reference

    - by ScottE
    I have an existing project that consumes web services. One was added as a service reference, and the other as a web reference. I don't recall why one was added as a web reference, but perhaps it's because I couldn't get it to work! The existing service reference for the one web service works fine, so it's not a .net version issue. I can successfully create a service reference for the second web service, but none of the methods are available. The .wsdl shows the schema, but the Reference.vb shows only the Namespace, and none of the methods. To clarify, these are two different 3rd party web service providers. We'd like to move to the service reference so we have more control over the configuration as we're having various issues with timeouts. Anyone come across this before? Edit Does it matter that there are two services at the address?

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  • Visual Studio compiles WPF application twice during build

    - by Brian Ensink
    I have a WPF app in VS2008 that compiles twice during the build. The two CSC command lines are similar but with some differences. The first CSC command line does not have an /resource options, the second has two /resource options on the command line. The second CSC command line has these additional arguments: /resource:"obj\Debug AutoCAD\VisualApp.g.resources" /resource:"obj\Debug AutoCAD\CAP.Visual.Properties.Resources.resources" I hate to post such a huge ugly compiler output but here are both command lines. 2>c:\WINDOWS\Microsoft.NET\Framework\v3.5\Csc.exe /noconfig /nowarn:1701,1702 /platform:x86 /errorreport:prompt /warn:4 /define:DEBUG;TRACE /reference:..\BIN\RELEASE\FOO.Base.dll /reference:..\BIN\RELEASE\FOO.CAPArchiveHandler.dll /reference:..\BIN\RELEASE\FOO.CAPDOM.dll /reference:"C:\Program Files\Reference Assemblies\Microsoft\Framework\v3.0\PresentationCore.dll" /reference:"C:\Program Files\Reference Assemblies\Microsoft\Framework\v3.0\PresentationFramework.dll" /reference:"c:\Program Files\Reference Assemblies\Microsoft\Framework\v3.5\System.Core.dll" /reference:"c:\Program Files\Reference Assemblies\Microsoft\Framework\v3.5\System.Data.DataSetExtensions.dll" /reference:c:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\System.Data.dll /reference:c:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\System.dll /reference:"C:\Program Files\Reference Assemblies\Microsoft\Framework\v3.0\System.Runtime.Serialization.dll" /reference:c:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\System.Xml.dll /reference:"c:\Program Files\Reference Assemblies\Microsoft\Framework\v3.5\System.Xml.Linq.dll" /reference:"C:\Program Files\Telerik\RadControls for WPF Q1 2010\Binaries\WPF\Telerik.Windows.Controls.dll" /reference:"C:\Program Files\Telerik\RadControls for WPF Q1 2010\Binaries\WPF\Telerik.Windows.Controls.Docking.dll" /reference:"C:\Program Files\Telerik\RadControls for WPF Q1 2010\Binaries\WPF\Telerik.Windows.Controls.Navigation.dll" /reference:"C:\Program Files\Reference Assemblies\Microsoft\Framework\v3.0\UIAutomationProvider.dll" /reference:c:\project\FooStudio\BIN\DEBUGCAD\VS-3DEngine-Wrapper.dll /reference:c:\project\FooStudio\BIN\DEBUGCAD\VisualServiceClient.dll /reference:"C:\Program Files\Reference Assemblies\Microsoft\Framework\v3.0\WindowsBase.dll" /debug+ /debug:full /filealign:512 /out:"obj\Debug AutoCAD\VisualApp.exe" /target:winexe App.xaml.cs MainWindow.xaml.cs CameraAndLightingControl.xaml.cs CameraAndLightingViewModel.cs MainWindowViewModel.cs Properties\AssemblyInfo.cs Properties\Resources.Designer.cs Properties\Settings.Designer.cs ScenarioToolsWindow.xaml.cs SceneGraph.cs ScenePart.cs ToolWindow.xaml.cs "c:\project\FooStudio\VisualApp\obj\Debug AutoCAD\CameraAndLightingControl.g.cs" "c:\project\FooStudio\VisualApp\obj\Debug AutoCAD\MainWindow.g.cs" "c:\project\FooStudio\VisualApp\obj\Debug AutoCAD\ScenarioToolsWindow.g.cs" "c:\project\FooStudio\VisualApp\obj\Debug AutoCAD\ToolWindow.g.cs" "c:\project\FooStudio\VisualApp\obj\Debug AutoCAD\App.g.cs" "c:\project\FooStudio\VisualApp\obj\Debug AutoCAD\GeneratedInternalTypeHelper.g.cs" 2>Done building project "0ye0i4wb.tmp_proj". 2>c:\WINDOWS\Microsoft.NET\Framework\v3.5\Csc.exe /noconfig /nowarn:1701,1702 /platform:x86 /errorreport:prompt /warn:4 /define:DEBUG;TRACE /reference:..\BIN\RELEASE\FOO.Base.dll /reference:..\BIN\RELEASE\FOO.CAPArchiveHandler.dll /reference:..\BIN\RELEASE\FOO.CAPDOM.dll /reference:"C:\Program Files\Reference Assemblies\Microsoft\Framework\v3.0\PresentationCore.dll" /reference:"C:\Program Files\Reference Assemblies\Microsoft\Framework\v3.0\PresentationFramework.dll" /reference:"c:\Program Files\Reference Assemblies\Microsoft\Framework\v3.5\System.Core.dll" /reference:"c:\Program Files\Reference Assemblies\Microsoft\Framework\v3.5\System.Data.DataSetExtensions.dll" /reference:c:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\System.Data.dll /reference:c:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\System.dll /reference:"C:\Program Files\Reference Assemblies\Microsoft\Framework\v3.0\System.Runtime.Serialization.dll" /reference:c:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\System.Xml.dll /reference:"c:\Program Files\Reference Assemblies\Microsoft\Framework\v3.5\System.Xml.Linq.dll" /reference:"C:\Program Files\Telerik\RadControls for WPF Q1 2010\Binaries\WPF\Telerik.Windows.Controls.dll" /reference:"C:\Program Files\Telerik\RadControls for WPF Q1 2010\Binaries\WPF\Telerik.Windows.Controls.Docking.dll" /reference:"C:\Program Files\Telerik\RadControls for WPF Q1 2010\Binaries\WPF\Telerik.Windows.Controls.Navigation.dll" /reference:"C:\Program Files\Reference Assemblies\Microsoft\Framework\v3.0\UIAutomationProvider.dll" /reference:c:\project\FooStudio\BIN\DEBUGCAD\VS-3DEngine-Wrapper.dll /reference:c:\project\FooStudio\BIN\DEBUGCAD\VisualServiceClient.dll /reference:"C:\Program Files\Reference Assemblies\Microsoft\Framework\v3.0\WindowsBase.dll" /debug+ /debug:full /filealign:512 /out:"obj\Debug AutoCAD\VisualApp.exe" /resource:"obj\Debug AutoCAD\VisualApp.g.resources" /resource:"obj\Debug AutoCAD\FOO.Visual.Properties.Resources.resources" /target:winexe App.xaml.cs MainWindow.xaml.cs CameraAndLightingControl.xaml.cs CameraAndLightingViewModel.cs MainWindowViewModel.cs Properties\AssemblyInfo.cs Properties\Resources.Designer.cs Properties\Settings.Designer.cs ScenarioToolsWindow.xaml.cs SceneGraph.cs ScenePart.cs ToolWindow.xaml.cs "c:\project\FooStudio\VisualApp\obj\Debug AutoCAD\CameraAndLightingControl.g.cs" "c:\project\FooStudio\VisualApp\obj\Debug AutoCAD\MainWindow.g.cs" "c:\project\FooStudio\VisualApp\obj\Debug AutoCAD\ScenarioToolsWindow.g.cs" "c:\project\FooStudio\VisualApp\obj\Debug AutoCAD\ToolWindow.g.cs" "c:\project\FooStudio\VisualApp\obj\Debug AutoCAD\App.g.cs" "c:\project\FooStudio\VisualApp\obj\Debug AutoCAD\GeneratedInternalTypeHelper.g.cs" Any idea what could possibly cause this? I think this is causing a problem I posted about earlier today.

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  • Why wasn't C# designed with 'const' for variables and methods?

    - by spoulson
    I suspect const was simplified for the C# spec for general language simplicity. Was there a specific reason we can't declare variable references or methods as const like we can with C++? e.g.: const MyObject o = new MyObject(); // Want const cast referenece of MyObject o.SomeMethod(); // Theoretically legal because SomeMethod is const o.ChangeStuff(); // Theoretically illegal because ChangeStuff is not const class MyObject { public int val = 0; public void SomeMethod() const { // Do stuff, but can't mutate due to const declaration. } public void ChangeStuff() { // Code mutates this instance. Can't call with const reference. val++; } }

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  • A reference that is not to 'const' cannot be bound to a non-lvalue

    - by Bert
    Hello, Am struggling a bit with this. Am declaring: BYTE *pImage = NULL; Used in call: m_pMyInterface-GetImage(i, &imageSize, &pImage); Visual C++ 2003 compiler error: error C2664: 'CJrvdInterface::GetImage' : cannot convert parameter 3 from 'BYTE **__w64 ' to 'BYTE **& ' A reference that is not to 'const' cannot be bound to a non-lvalue The method called is defined as: void CMyInterface::GetImage(const int &a_iTileId, ULONG *a_pulImageSize, BYTE** &a_ppbImage) { (...) Any help much appreciated, Bert

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  • build error with boost spirit grammar (boost 1.43 and g++ 4.4.1)

    - by lurscher
    I'm having issues getting a small spirit/qi grammar to compile. The build stack trace is fugly enought to not make any sense to me (despite some assertion_failed i could notice in there but that didn't brought much information) the input grammar header: inputGrammar.h #include <boost/config/warning_disable.hpp> #include <boost/spirit/include/qi.hpp> #include <boost/spirit/include/phoenix_core.hpp> #include <boost/spirit/include/phoenix_operator.hpp> #include <boost/spirit/include/phoenix_fusion.hpp> #include <boost/spirit/include/phoenix_stl.hpp> #include <boost/fusion/include/adapt_struct.hpp> #include <boost/variant/recursive_variant.hpp> #include <boost/foreach.hpp> #include <iostream> #include <fstream> #include <string> #include <vector> namespace sp = boost::spirit; namespace qi = boost::spirit::qi; using namespace boost::spirit::ascii; //using namespace boost::spirit::arg_names; namespace fusion = boost::fusion; namespace phoenix = boost::phoenix; using phoenix::at_c; using phoenix::push_back; template< typename Iterator , typename ExpressionAST > struct InputGrammar : qi::grammar<Iterator, ExpressionAST(), space_type> { InputGrammar() : InputGrammar::base_type( block ) { tag = sp::lexeme[+(alpha) [sp::_val += sp::_1]];//[+(char_ - '<') [_val += _1]]; block = sp::lit("block") [ at_c<0>(sp::_val) = sp::_1] >> "(" >> *instruction[ push_back( at_c<1>(sp::_val) , sp::_1 ) ] >> ")"; command = tag [ at_c<0>(sp::_val) = sp::_1] >> "(" >> *instruction [ push_back( at_c<1>(sp::_val) , sp::_1 )] >> ")"; instruction = ( command | tag ) [sp::_val = sp::_1]; } qi::rule< Iterator , std::string() , space_type > tag; qi::rule< Iterator , ExpressionAST() , space_type > block; qi::rule< Iterator , ExpressionAST() , space_type > function_def; qi::rule< Iterator , ExpressionAST() , space_type > command; qi::rule< Iterator , ExpressionAST() , space_type > instruction; }; the test build program: i seems the build fails at qi::phrase_parse, i am using boost 1.43 and g++ 4.4.1 #include <iostream> #include <string> #include <vector> using namespace std; //my grammar #include <InputGrammar.h> struct MockExpressionNode { std::string name; std::vector< MockExpressionNode > operands; typedef std::vector< MockExpressionNode >::iterator iterator; typedef std::vector< MockExpressionNode >::const_iterator const_iterator; iterator begin() { return operands.begin(); } const_iterator begin() const { return operands.begin(); } iterator end() { return operands.end(); } const_iterator end() const { return operands.end(); } bool is_leaf() const { return ( operands.begin() == operands.end() ); } }; BOOST_FUSION_ADAPT_STRUCT( MockExpressionNode, (std::string, name) (std::vector<MockExpressionNode>, operands) ) int const tabsize = 4; void tab(int indent) { for (int i = 0; i < indent; ++i) std::cout << ' '; } template< typename ExpressionNode > struct ExpressionNodePrinter { ExpressionNodePrinter(int indent = 0) : indent(indent) { } void operator()(ExpressionNode const& node) const { cout << " tag: " << node.name << endl; for (int i=0 ; i < node.operands.size() ; i++ ) { tab( indent ); cout << " arg "<<i<<": "; ExpressionNodePrinter(indent + 2)( node.operands[i]); cout << endl; } } int indent; }; int test() { MockExpressionNode root; InputGrammar< string::const_iterator , MockExpressionNode > g(); std::string litA = "litA"; std::string litB = "litB"; std::string litC = "litC"; std::string litD = "litD"; std::string litE = "litE"; std::string litF = "litF"; std::string source = litA+"( "+litB+" ,"+litC+" , "+ litD+" ( "+litE+", "+litF+" ) "+ " )"; string::const_iterator iter = source.begin(); string::const_iterator end = source.end(); bool r = qi::phrase_parse( iter , end , g , root , space ); ExpressionNodePrinter< MockExpressionNode > np; np( root ); }; int main() { test(); } finally, the build error is the following: /usr/bin/make -f nbproject/Makefile-linux_amd64_devel.mk SUBPROJECTS= .build-conf make[1]: se ingresa al directorio `/home/mineq/NetBeansProjects/InputParserTests' /usr/bin/make -f nbproject/Makefile-linux_amd64_devel.mk dist/linux_amd64_devel/GNU-Linux-x86/vpuinputparsertests make[2]: se ingresa al directorio `/home/mineq/NetBeansProjects/InputParserTests' mkdir -p build/linux_amd64_devel/GNU-Linux-x86 rm -f build/linux_amd64_devel/GNU-Linux-x86/tests_main.o.d g++ `llvm-config --cxxflags` `pkg-config --cflags unittest-cpp` `pkg-config --cflags boost-1.43` `pkg-config --cflags boost-coroutines` -c -g -I../InputParser -MMD -MP -MF build/linux_amd64_devel/GNU-Linux-x86/tests_main.o.d -o build/linux_amd64_devel/GNU-Linux-x86/tests_main.o tests_main.cpp from /home/mineq/third_party/boost_1_43_0/boost/spirit/home/qi/auto.hpp:16, from /home/mineq/third_party/boost_1_43_0/boost/spirit/home/qi.hpp:15, from /home/mineq/third_party/boost_1_43_0/boost/spirit/include/qi.hpp:16, from ../InputParser/InputGrammar.h:12, from tests_main.cpp:14: /home/mineq/third_party/boost_1_43_0/boost/spirit/home/qi/parse.hpp: In function ‘bool boost::spirit::qi::phrase_parse(Iterator&, Iterator, const Expr&, const Skipper&, boost::spirit::qi::skip_flag::enum_type, Attr&) [with Iterator = __gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, Expr = InputGrammar<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, MockExpressionNode>(), Skipper = MockExpressionNode, Attr = const boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::term<boost::spirit::tag::char_code<boost::spirit::tag::space, boost::spirit::char_encoding::ascii> >, 0l>]’: In file included from /home/mineq/third_party/boost_1_43_0/boost/spirit/home/qi/detail/parse_auto.hpp:14, /home/mineq/third_party/boost_1_43_0/boost/spirit/home/qi/parse.hpp:125: instantiated from ‘bool boost::spirit::qi::phrase_parse(Iterator&, Iterator, const Expr&, const Skipper&, Attr&) [with Iterator = __gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, Expr = InputGrammar<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, MockExpressionNode>(), Skipper = MockExpressionNode, Attr = const boost::spirit::ascii::space_type]’ tests_main.cpp:206: instantiated from here /home/mineq/third_party/boost_1_43_0/boost/spirit/home/qi/parse.hpp:99: error: no matching function for call to ‘assertion_failed(mpl_::failed************ (boost::spirit::qi::phrase_parse(Iterator&, Iterator, const Expr&, const Skipper&, boost::spirit::qi::skip_flag::enum_type, Attr&) [with Iterator = __gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, Expr = InputGrammar<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, MockExpressionNode>(), Skipper = MockExpressionNode, Attr = const boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::term<boost::spirit::tag::char_code<boost::spirit::tag::space, boost::spirit::char_encoding::ascii> >, 0l>]::error_invalid_expression::************)(InputGrammar<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, MockExpressionNode> (*)()))’ /home/mineq/third_party/boost_1_43_0/boost/spirit/home/qi/parse.hpp:125: instantiated from ‘bool boost::spirit::qi::phrase_parse(Iterator&, Iterator, const Expr&, const Skipper&, Attr&) [with Iterator = __gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, Expr = InputGrammar<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, MockExpressionNode>(), Skipper = MockExpressionNode, Attr = const boost::spirit::ascii::space_type]’ tests_main.cpp:206: instantiated from here /home/mineq/third_party/boost_1_43_0/boost/spirit/home/qi/parse.hpp:100: error: no matching function for call to ‘assertion_failed(mpl_::failed************ (boost::spirit::qi::phrase_parse(Iterator&, Iterator, const Expr&, const Skipper&, boost::spirit::qi::skip_flag::enum_type, Attr&) [with Iterator = __gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, Expr = InputGrammar<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, MockExpressionNode>(), Skipper = MockExpressionNode, Attr = const boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::term<boost::spirit::tag::char_code<boost::spirit::tag::space, boost::spirit::char_encoding::ascii> >, 0l>]::error_invalid_expression::************)(MockExpressionNode))’ from /home/mineq/third_party/boost_1_43_0/boost/proto/proto.hpp:12, from /home/mineq/third_party/boost_1_43_0/boost/spirit/home/support/meta_compiler.hpp:17, from /home/mineq/third_party/boost_1_43_0/boost/spirit/home/qi/meta_compiler.hpp:14, from /home/mineq/third_party/boost_1_43_0/boost/spirit/home/qi/action/action.hpp:14, from /home/mineq/third_party/boost_1_43_0/boost/spirit/home/qi/action.hpp:14, from /home/mineq/third_party/boost_1_43_0/boost/spirit/home/qi.hpp:14, from /home/mineq/third_party/boost_1_43_0/boost/spirit/include/qi.hpp:16, from ../InputParser/InputGrammar.h:12, from tests_main.cpp:14: /home/mineq/third_party/boost_1_43_0/boost/proto/detail/expr0.hpp: At global scope: /home/mineq/third_party/boost_1_43_0/boost/proto/proto_fwd.hpp: In instantiation of ‘boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::term<InputGrammar<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, MockExpressionNode>()>, 0l>’: In file included from /home/mineq/third_party/boost_1_43_0/boost/proto/core.hpp:13, /home/mineq/third_party/boost_1_43_0/boost/utility/enable_if.hpp:59: instantiated from ‘boost::disable_if<boost::proto::result_of::is_expr<boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::term<InputGrammar<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, MockExpressionNode>()>, 0l>, void>, void>’ /home/mineq/third_party/boost_1_43_0/boost/spirit/home/support/meta_compiler.hpp:200: instantiated from ‘boost::spirit::result_of::compile<boost::spirit::qi::domain, InputGrammar<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, MockExpressionNode>(), boost::fusion::unused_type, void>’ /home/mineq/third_party/boost_1_43_0/boost/spirit/home/qi/parse.hpp:107: instantiated from ‘bool boost::spirit::qi::phrase_parse(Iterator&, Iterator, const Expr&, const Skipper&, boost::spirit::qi::skip_flag::enum_type, Attr&) [with Iterator = __gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, Expr = InputGrammar<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, MockExpressionNode>(), Skipper = MockExpressionNode, Attr = const boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::term<boost::spirit::tag::char_code<boost::spirit::tag::space, boost::spirit::char_encoding::ascii> >, 0l>]’ /home/mineq/third_party/boost_1_43_0/boost/spirit/home/qi/parse.hpp:125: instantiated from ‘bool boost::spirit::qi::phrase_parse(Iterator&, Iterator, const Expr&, const Skipper&, Attr&) [with Iterator = __gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, Expr = InputGrammar<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, MockExpressionNode>(), Skipper = MockExpressionNode, Attr = const boost::spirit::ascii::space_type]’ tests_main.cpp:206: instantiated from here /home/mineq/third_party/boost_1_43_0/boost/proto/detail/expr0.hpp:64: error: field ‘boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::term<InputGrammar<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, MockExpressionNode>()>, 0l>::child0’ invalidly declared function type from /home/mineq/third_party/boost_1_43_0/boost/spirit/home/qi/auto.hpp:16, from /home/mineq/third_party/boost_1_43_0/boost/spirit/home/qi.hpp:15, from /home/mineq/third_party/boost_1_43_0/boost/spirit/include/qi.hpp:16, from ../InputParser/InputGrammar.h:12, from tests_main.cpp:14: /home/mineq/third_party/boost_1_43_0/boost/spirit/home/qi/parse.hpp: In function ‘bool boost::spirit::qi::phrase_parse(Iterator&, Iterator, const Expr&, const Skipper&, boost::spirit::qi::skip_flag::enum_type, Attr&) [with Iterator = __gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, Expr = InputGrammar<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, MockExpressionNode>(), Skipper = MockExpressionNode, Attr = const boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::term<boost::spirit::tag::char_code<boost::spirit::tag::space, boost::spirit::char_encoding::ascii> >, 0l>]’: In file included from /home/mineq/third_party/boost_1_43_0/boost/spirit/home/qi/detail/parse_auto.hpp:14, /home/mineq/third_party/boost_1_43_0/boost/spirit/home/qi/parse.hpp:125: instantiated from ‘bool boost::spirit::qi::phrase_parse(Iterator&, Iterator, const Expr&, const Skipper&, Attr&) [with Iterator = __gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, Expr = InputGrammar<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, MockExpressionNode>(), Skipper = MockExpressionNode, Attr = const boost::spirit::ascii::space_type]’ tests_main.cpp:206: instantiated from here /home/mineq/third_party/boost_1_43_0/boost/spirit/home/qi/parse.hpp:107: error: request for member ‘parse’ in ‘boost::spirit::compile [with Domain = boost::spirit::qi::domain, Expr = InputGrammar<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, MockExpressionNode>()](((InputGrammar<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, MockExpressionNode> (&)())((InputGrammar<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, MockExpressionNode> (*)())expr)))’, which is of non-class type ‘InputGrammar<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, MockExpressionNode>()’ from /home/mineq/third_party/boost_1_43_0/boost/spirit/home/qi/auto.hpp:15, from /home/mineq/third_party/boost_1_43_0/boost/spirit/home/qi.hpp:15, from /home/mineq/third_party/boost_1_43_0/boost/spirit/include/qi.hpp:16, from ../InputParser/InputGrammar.h:12, from tests_main.cpp:14: /home/mineq/third_party/boost_1_43_0/boost/spirit/home/qi/skip_over.hpp: In function ‘void boost::spirit::qi::skip_over(Iterator&, const Iterator&, const T&) [with Iterator = __gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, T = boost::spirit::qi::phrase_parse(Iterator&, Iterator, const Expr&, const Skipper&, boost::spirit::qi::skip_flag::enum_type, Attr&) [with Iterator = __gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, Expr = InputGrammar<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, MockExpressionNode>(), Skipper = MockExpressionNode, Attr = const boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::term<boost::spirit::tag::char_code<boost::spirit::tag::space, boost::spirit::char_encoding::ascii> >, 0l>]::skipper_type]’: In file included from /home/mineq/third_party/boost_1_43_0/boost/spirit/home/qi/auto/auto.hpp:19, /home/mineq/third_party/boost_1_43_0/boost/spirit/home/qi/parse.hpp:112: instantiated from ‘bool boost::spirit::qi::phrase_parse(Iterator&, Iterator, const Expr&, const Skipper&, boost::spirit::qi::skip_flag::enum_type, Attr&) [with Iterator = __gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, Expr = InputGrammar<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, MockExpressionNode>(), Skipper = MockExpressionNode, Attr = const boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::term<boost::spirit::tag::char_code<boost::spirit::tag::space, boost::spirit::char_encoding::ascii> >, 0l>]’ /home/mineq/third_party/boost_1_43_0/boost/spirit/home/qi/parse.hpp:125: instantiated from ‘bool boost::spirit::qi::phrase_parse(Iterator&, Iterator, const Expr&, const Skipper&, Attr&) [with Iterator = __gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, Expr = InputGrammar<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, MockExpressionNode>(), Skipper = MockExpressionNode, Attr = const boost::spirit::ascii::space_type]’ tests_main.cpp:206: instantiated from here /home/mineq/third_party/boost_1_43_0/boost/spirit/home/qi/skip_over.hpp:27: error: ‘const struct MockExpressionNode’ has no member named ‘parse’ make[2]: *** [build/linux_amd64_devel/GNU-Linux-x86/tests_main.o] Error 1 make[2]: se sale del directorio `/home/mineq/NetBeansProjects/InputParserTests' make[1]: *** [.build-conf] Error 2 make[1]: se sale del directorio `/home/mineq/NetBeansProjects/InputParserTests' make: *** [.build-impl] Error 2 BUILD FAILED (exit value 2, total time: 1m 48s)

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  • Undefined reference to ...

    - by Patrick LaChance
    I keep getting this error message every time I try to compile, and I cannot find out what the problem is. any help would be greatly appreciated: C:\DOCUME~1\Patrick\LOCALS~1\Temp/ccL92mj9.o:main.cpp:(.txt+0x184): undefined reference to 'List::List()' C:\DOCUME~1\Patrick\LOCALS~1\Temp/ccL92mj9.o:main.cpp:(.txt+0x184): undefined reference to 'List::add(int)' collect2: ld returned 1 exit status code: //List.h #ifndef LIST_H #define LIST_H #include <exception> //brief Definition of linked list class class List { public: /** \brief Exception for operating on empty list */ class Empty : public std::exception { public: virtual const char* what() const throw(); }; /** \brief Exception for invalid operations other than operating on an empty list */ class InvalidOperation : public std::exception { public: virtual const char* what() const throw(); }; /** \brief Node within List */ class Node { public: /** data element stored in this node */ int element; /** next node in list */ Node* next; /** previous node in list */ Node* previous; Node (int element); ~Node(); void print() const; void printDebug() const; }; List(); ~List(); void add(int element); void remove(int element); int first()const; int last()const; int removeFirst(); int removeLast(); bool isEmpty()const; int size()const; void printForward() const; void printReverse() const; void printDebug() const; /** enables extra output for debugging purposes */ static bool traceOn; private: /** head of list */ Node* head; /** tail of list */ Node* tail; /** count of number of nodes */ int count; }; #endif //List.cpp I only included the parts of List.cpp that might be the issue #include "List.h" #include <iostream> #include <iomanip> using namespace std; List::List() { //List::size = NULL; head = NULL; tail = NULL; } List::~List() { Node* current; while(head != NULL) { current = head-> next; delete current->previous; if (current->next!=NULL) { head = current; } else { delete current; } } } void List::add(int element) { Node* newNode; Node* current; newNode->element = element; if(newNode->element > head->element) { current = head->next; } else { head->previous = newNode; newNode->next = head; newNode->previous = NULL; return; } while(newNode->element > current->element) { current = current->next; } if(newNode->element <= current->element) { newNode->previous = current->previous; newNode->next = current; } } //main.cpp #include "List.h" #include <iostream> #include <string> using namespace std; //void add(int element); int main (char** argv, int argc) { List* MyList = new List(); bool quit = false; string value; int element; while(quit==false) { cin>>value; if(value == "add") { cin>>element; MyList->add(element); } if(value=="quit") { quit = true; } } return 0; } I'm doing everything I think I'm suppose to be doing. main.cpp isn't complete yet, just trying to get the add function to work first. Any help will be greatly appreciated.

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  • const object in c++

    - by Codenotguru
    I have a question on constant objects. In the following program: class const_check{ int a; public: const_check(int i); void print() const; void print2(); }; const_check::const_check(int i):a(i) {} void const_check::print() const { int a=19; cout<<"The value in a is:"<<a; } void const_check::print2() { int a=10; cout<<"The value in a is:"<<a; } int main(){ const_check b(5); const const_check c(6); b.print2(); c.print(); } void print() is constant member function of the class const_check, so according to the definition of constants if any attempt to change int a it should result in an error but the program works fine for me.I think i am having some confusion here, can anybody tell me why the compiler is not flagging it as an error??

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  • boost::dynamic_pointer_cast with const pointer not working ?

    - by ereOn
    Hi, Let's say I have two classes, A and B, where B is a child class of A. I also have the following function: void foo(boost::shared_ptr<const A> a) { boost::shared_ptr<const B> b = boost::dynamic_pointer_cast<const B>(a); // Error ! } Compilation with gcc gives me the following errors: C:\Boost\include/boost/smart_ptr/shared_ptr.hpp: In constructor 'boost::shared_ptr< <template-parameter-1-1> >::shared_ptr(const boost::shared_ptr<Y>&, boost::detail::dynamic_cast_tag) [with Y = const A, T = const B]': C:\Boost\include/boost/smart_ptr/shared_ptr.hpp:522: instantiated from 'boost::shared_ptr<X> boost::dynamic_pointer_cast(const boost::shared_ptr<U>&) [with T = const B, U = const A]' src\a.cpp:10: instantiated from here C:\Boost\include/boost/smart_ptr/shared_ptr.hpp:259: error: cannot dynamic_cast 'r->boost::shared_ptr<const A>::px' (of type 'const class A* const') to type 'const class B*' (source type is not polymorphic) What could possibly be wrong ? Thank you.

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  • When does a const return type interfere with template instantiation?

    - by Rimo
    From Herb Sutter's GotW #6 Return-by-value should normally be const for non-builtin return types. ... Note: Lakos (pg. 618) argues against returning const value, and notes that it is redundant for builtins anyway (for example, returning "const int"), which he notes may interfere with template instantiation. While Sutter seems to disagree on whether to return a const value or non-const value when returning an object of a non-built type by value with Lakos, he generally agrees that returning a const value of a built-in type (e.g const int) is not a good idea. While I understand why that is useless because the return value cannot be modified as it is an rvalue, I cannot find an example of how that might interfere with template instantiation. Please give me an example of how having a const qualifier for a return type might interfere with template instantiation.

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  • Python to C/C++ const char question

    - by tsukemonoki
    I am extending Python with some C++ code. One of the functions I'm using has the following signature: int PyArg_ParseTupleAndKeywords(PyObject *arg, PyObject *kwdict, char *format, char **kwlist, ...); (link: http://docs.python.org/release/1.5.2p2/ext/parseTupleAndKeywords.html) The parameter of interest is kwlist. In the link above, examples on how to use this function are given. In the examples, kwlist looks like: static char *kwlist[] = {"voltage", "state", "action", "type", NULL}; When I compile this using g++, I get the warning: warning: deprecated conversion from string constant to ‘char*’ So, I can change the static char* to a static const char*. Unfortunately, I can't change the Python code. So with this change, I get a different compilation error (can't convert char** to const char**). Based on what I've read here, I can turn on compiler flags to ignore the warning or I can cast each of the constant strings in the definition of kwlist to char *. Currently, I'm doing the latter. What are other solutions? Sorry if this question has been asked before. I'm new.

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