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POUnwrapping a boost::function from boost::python::object with extract
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2012-12-19T21:27:58.817
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How can I call C++ module functions from C++ but select the function from python? See example below I know I can setup a map of strings manually, and select the function I want to run, but I'd like a cleaner python solution. I would also like it to be very efficient, hopefully by basically unwrapping the boost::python::object and extracting the boost::function<> out of it. Here is the python file <pre><code>import stackoverflow #this is a C++ module I wrote t = stackoverflow.TestClass() t.Reference() # time invoking a boost::function 100k times t.CallSomeClassMemberFunction(t.a) # instead of choosing a function directly, i want to pass in which function I want to invoke from python </code></pre> C++ module code (compiles, but does not run.. you can see my intent): <pre><code>#include <sys/time.h> #include <stdlib.h> #include <boost/function.hpp> #include <boost/python.hpp> struct TestClass { TestClass() { } int a() const { return rand()%4; } int b() const { return rand()%64; } template<typename T> void BenchMark(T & aUnknownFunction) { timeval begin, end; long long sum(0); gettimeofday(&begin, NULL); __asm__ __volatile__ ("cpuid"); for (int x(0); x!=100000; ++x) sum += aUnknownFunction(); __asm__ __volatile__ ("cpuid"); gettimeofday(&end, NULL); std::cout << "Time: " << 1000000 * (end.tv_sec - begin.tv_sec) + (end.tv_usec - begin.tv_usec) << std::endl; srand(sum); } void CallSomeClassMemberFunction(boost::python::object &aTest) { boost::function<int ()> unknownFunction = boost::python::extract<boost::function<int ()> >(aTest) ; // i don't think this works as I want BenchMark( unknownFunction ); } void Reference() { boost::function<int ()> unknownFunction = boost::bind(&TestClass::a, this); BenchMark( unknownFunction ); } }; BOOST_PYTHON_MODULE(stackoverflow) { boost::python::class_<TestClass>("TestClass") .def("a",&TestClass::a) .def("b",&TestClass::b) .def("CallSomeClassMemberFunction",&TestClass::CallSomeClassMemberFunction) .def("Reference",&TestClass::Reference) ; } </code></pre> If you can get it to run, would love to see your timings as well.
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<c++><boost><boost-python><boost-function>
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Unwrapping a boost::function from boost::python::object with extract
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