[Boost-users] Using boost function with virtual methods

Subject: [Boost-users] Using boost function with virtual methods
From: przemyslaw.sliwa_at_[hidden]
Date: 2011-07-01 13:06:22

Hi,

I have a simple inheritance:

class A {};

class RegressionTestScenario;

typedef A CurveGen;
typedef boost::shared_ptr<CurveGen>  CurveGenPtr;
typedef boost::function<void (RegressionTestScenario*, const std::string 
&)>     actionFuntion;
typedef boost::shared_ptr<actionFuntion>  actionFuntionPtr;

class RegressionTestScenario
{
public:
        virtual ~RegressionTestScenario() {}

        virtual void doScenario() = 0;
        virtual boost::shared_ptr<std::string> fileName() const = 0;
        virtual boost::shared_ptr<std::string> print() const = 0;
        virtual void unwrapPackage(const std::string &contents) = 0;

protected:
        typedef std::vector<std::pair<actionFuntionPtr, std::string> > 
actionCollection;

        actionCollection m_actionCollection;
};

class CurveGenRegressionTestScenario : public RegressionTestScenario
{
public:
        virtual void doScenario();
        virtual boost::shared_ptr<std::string> fileName() const;
        virtual boost::shared_ptr<std::string> print() const;
        virtual void unwrapPackage(const std::string &contents);

private:
        CurveGenPtr     m_curveGenPtr;

        void addAction(const std::string &action);
        void changeBaseDate(const std::string &argument);
        void changeStvParameter(const std::string &argument);
        void changeLtvParameter(const std::string &argument);
        void changeHalfLife(const std::string &argument);
        void changeParameterSet(const std::string &argument);
        void changeCurrencyCouple(const std::string &argument);
};

and I am trying to use the following:

        actionFuntion funPtr;

        if(params[0]=="BaseDate")
                funPtr = &CurveGenRegressionTestScenario::changeBaseDate;

but it fails. I have no idea why. Could someone give me a hint? This is 
the output from the compiler:

Cheers

1>------ Build started: Project: compare, Configuration: Release Win32 
------
1>Compiling...
1>RegressionTestMain.cpp
1>D:\Dev\SOHO_NEW\Thirdparty\boost/bind/mem_fn_template.hpp(156) : error 
C2440: 'newline' : cannot convert from 'RegressionTestScenario *' to 
'CurveGenRegressionTestScenario *'
1>        Cast from base to derived requires dynamic_cast or static_cast
1>        D:\Dev\SOHO_NEW\Thirdparty\boost/bind/mem_fn_template.hpp(171) : 
see reference to function template instantiation 'R 
boost::_mfi::mf1<R,T,A1>::call<U,const std::string>(U &,const void *,B1 &) 
const' being compiled
1>        with
1>        [
1>            R=void,
1>            T=CurveGenRegressionTestScenario,
1>            A1=const std::string &,
1>            U=RegressionTestScenario *,
1>            B1=const std::string
1>        ]
1> D:\Dev\SOHO_NEW\Thirdparty\boost/function/function_template.hpp(225) : 
see reference to function template instantiation 'R 
boost::_mfi::mf1<R,T,A1>::operator ()<T0>(U &,A1) const' being compiled
1>        with
1>        [
1>            R=void,
1>            T=CurveGenRegressionTestScenario,
1>            A1=const std::string &,
1>            T0=RegressionTestScenario *,
1>            U=RegressionTestScenario *
1>        ]
1> D:\Dev\SOHO_NEW\Thirdparty\boost/function/function_template.hpp(222) : 
while compiling class template member function 'void 
boost::detail::function::function_void_mem_invoker2<MemberPtr,R,T0,T1>::invoke(boost::detail::function::function_buffer 
&,T0,T1)'
1>        with
1>        [
1>            MemberPtr=void (__thiscall CurveGenRegressionTestScenario::* 
)(const std::string &),
1>            R=void,
1>            T0=RegressionTestScenario *,
1>            T1=const 
std::basic_string<char,std::char_traits<char>,std::allocator<char>> &
1>        ]
1> D:\Dev\SOHO_NEW\Thirdparty\boost/function/function_template.hpp(913) : 
see reference to class template instantiation 
'boost::detail::function::function_void_mem_invoker2<MemberPtr,R,T0,T1>' 
being compiled
1>        with
1>        [
1>            MemberPtr=void (__thiscall CurveGenRegressionTestScenario::* 
)(const std::string &),
1>            R=void,
1>            T0=RegressionTestScenario *,
1>            T1=const 
std::basic_string<char,std::char_traits<char>,std::allocator<char>> &
1>        ]
1> D:\Dev\SOHO_NEW\Thirdparty\boost/function/function_template.hpp(722) : 
see reference to function template instantiation 'void 
boost::function2<R,T0,T1>::assign_to<Functor>(Functor)' being compiled
1>        with
1>        [
1>            R=void,
1>            T0=RegressionTestScenario *,
1>            T1=const 
std::basic_string<char,std::char_traits<char>,std::allocator<char>> &,
1>            Functor=void (__thiscall CurveGenRegressionTestScenario::* 
)(const std::string &)
1>        ]
1> D:\Dev\SOHO_NEW\Thirdparty\boost/function/function_template.hpp(1065) : 
see reference to function template instantiation 
'boost::function2<R,T0,T1>::function2<void(__thiscall 
CurveGenRegressionTestScenario::* )(const std::string &)>(Functor,int)' 
being compiled
1>        with
1>        [
1>            R=void,
1>            T0=RegressionTestScenario *,
1>            T1=const 
std::basic_string<char,std::char_traits<char>,std::allocator<char>> &,
1>            Functor=void (__thiscall CurveGenRegressionTestScenario::* 
)(const std::string &)
1>        ]
1> D:\Dev\SOHO_NEW\Thirdparty\boost/function/function_template.hpp(1105) : 
see reference to function template instantiation 
'boost::function<Signature>::function<void(__thiscall 
CurveGenRegressionTestScenario::* )(const std::string &)>(Functor,int)' 
being compiled
1>        with
1>        [
1>            Signature=void (RegressionTestScenario *,const std::string 
&),
1>            Functor=void (__thiscall CurveGenRegressionTestScenario::* 
)(const std::string &)
1>        ]
1>        .\RegressionTestMain.cpp(182) : see reference to function 
template instantiation 'boost::function<Signature> 
&boost::function<Signature>::operator =<void(__thiscall 
CurveGenRegressionTestScenario::* )(const std::string &)>(Functor)' being 
compiled
1>        with
1>        [
1>            Signature=void (RegressionTestScenario *,const std::string 
&),
1>            Functor=void (__thiscall CurveGenRegressionTestScenario::* 
)(const std::string &)
1>        ]
1>D:\Dev\SOHO_NEW\Thirdparty\boost/bind/mem_fn_template.hpp(156) : error 
C2647: '->*' : cannot dereference a 'void (__thiscall 
CurveGenRegressionTestScenario::* const )(A1)' on a 
'RegressionTestScenario *'
1>        with
1>        [
1>            A1=const std::string &
1>        ]
1>Build log was saved at 
"file://d:\Dev\OwnProgs\compare\compare\Release\BuildLog.htm"
1>compare - 2 error(s), 0 warning(s)
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped 
==========

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