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Header <call.hpp>




<boost/python/call.hpp> defines the call family of overloaded function templates, used to invoke Python callable objects from C++.


template <class R, class A1, class A2, ... class An>
R call(PyObject* callable, A1 const&, A2 const&, ... An const&)
Requires: R is a pointer type, reference type, or a complete type with an accessible copy constructor
Effects: Invokes callable(a1, a2, in Python, where are the arguments to call(), converted to Python objects.
Returns: The result of the Python call, converted to the C++ type R.
Rationale: For a complete semantic description and rationale, see this page.


The following C++ function applies a Python callable object to its two arguments and returns the result. If a Python exception is raised or the result can't be converted to a double, an exception is thrown.
double apply2(PyObject* func, double x, double y)
   return boost::python::call<double>(func, x, y);

Revised 9 May, 2002

© Copyright Dave Abrahams 2002.