[12] | 1 | // Copyright David Abrahams 2002. |
---|
| 2 | // Distributed under the Boost Software License, Version 1.0. (See |
---|
| 3 | // accompanying file LICENSE_1_0.txt or copy at |
---|
| 4 | // http://www.boost.org/LICENSE_1_0.txt) |
---|
| 5 | |
---|
| 6 | // embedded_hello -- A simple Boost.Python embedding example -- by |
---|
| 7 | // Dirk Gerrits |
---|
| 8 | |
---|
| 9 | #include <boost/python.hpp> |
---|
| 10 | #include <boost/scoped_ptr.hpp> |
---|
| 11 | #include <iostream> |
---|
| 12 | #include <stdexcept> |
---|
| 13 | #include <cassert> |
---|
| 14 | |
---|
| 15 | namespace python = boost::python; |
---|
| 16 | |
---|
| 17 | // An abstract base class |
---|
| 18 | class Base : public boost::noncopyable |
---|
| 19 | { |
---|
| 20 | public: |
---|
| 21 | virtual ~Base() {}; |
---|
| 22 | |
---|
| 23 | virtual std::string hello() = 0; |
---|
| 24 | }; |
---|
| 25 | |
---|
| 26 | // C++ derived class |
---|
| 27 | class CppDerived : public Base |
---|
| 28 | { |
---|
| 29 | public: |
---|
| 30 | virtual ~CppDerived() {} |
---|
| 31 | |
---|
| 32 | std::string hello() |
---|
| 33 | { |
---|
| 34 | return "Hello from C++!"; |
---|
| 35 | } |
---|
| 36 | }; |
---|
| 37 | |
---|
| 38 | // Familiar Boost.Python wrapper class for Base |
---|
| 39 | struct BaseWrap : public Base |
---|
| 40 | { |
---|
| 41 | BaseWrap(PyObject* self_) |
---|
| 42 | : self(self_) {} |
---|
| 43 | |
---|
| 44 | std::string hello() { return python::call_method<std::string>(self, "hello"); } |
---|
| 45 | |
---|
| 46 | PyObject* self; |
---|
| 47 | }; |
---|
| 48 | |
---|
| 49 | // Pack the Base class wrapper into a module |
---|
| 50 | BOOST_PYTHON_MODULE(embedded_hello) |
---|
| 51 | { |
---|
| 52 | python::class_<Base, BaseWrap, boost::noncopyable>("Base") |
---|
| 53 | ; |
---|
| 54 | |
---|
| 55 | } |
---|
| 56 | |
---|
| 57 | |
---|
| 58 | void test() |
---|
| 59 | { |
---|
| 60 | //- INITIALIZATION -----------------------------------------------------------// |
---|
| 61 | |
---|
| 62 | // Register the module with the interpreter |
---|
| 63 | if (PyImport_AppendInittab("embedded_hello", initembedded_hello) == -1) |
---|
| 64 | throw std::runtime_error("Failed to add embedded_hello to the interpreter's " |
---|
| 65 | "builtin modules"); |
---|
| 66 | // Retrieve the main module |
---|
| 67 | python::object main_module(( |
---|
| 68 | python::handle<>(python::borrowed(PyImport_AddModule("__main__"))))); |
---|
| 69 | |
---|
| 70 | // Retrieve the main module's namespace |
---|
| 71 | python::object main_namespace((main_module.attr("__dict__"))); |
---|
| 72 | |
---|
| 73 | // Define the derived class in Python. |
---|
| 74 | // (You'll normally want to put this in a .py file.) |
---|
| 75 | python::handle<> result( |
---|
| 76 | PyRun_String( |
---|
| 77 | "from embedded_hello import * \n" |
---|
| 78 | "class PythonDerived(Base): \n" |
---|
| 79 | " def hello(self): \n" |
---|
| 80 | " return 'Hello from Python!' \n", |
---|
| 81 | Py_file_input, main_namespace.ptr(), main_namespace.ptr()) |
---|
| 82 | ); |
---|
| 83 | // Result is not needed |
---|
| 84 | result.reset(); |
---|
| 85 | |
---|
| 86 | // Extract the raw Python object representing the just defined derived class |
---|
| 87 | python::handle<> class_ptr( |
---|
| 88 | PyRun_String("PythonDerived\n", Py_eval_input, |
---|
| 89 | main_namespace.ptr(), main_namespace.ptr()) ); |
---|
| 90 | |
---|
| 91 | // Wrap the raw Python object in a Boost.Python object |
---|
| 92 | python::object PythonDerived(class_ptr); |
---|
| 93 | |
---|
| 94 | //- MAIN PROGRAM -------------------------------------------------------------// |
---|
| 95 | |
---|
| 96 | // Creating and using instances of the C++ class is as easy as always. |
---|
| 97 | CppDerived cpp; |
---|
| 98 | std::cout << cpp.hello() << std::endl; |
---|
| 99 | |
---|
| 100 | // But now creating and using instances of the Python class is almost |
---|
| 101 | // as easy! |
---|
| 102 | python::object py_base = PythonDerived(); |
---|
| 103 | Base& py = python::extract<Base&>(py_base) |
---|
| 104 | #if BOOST_WORKAROUND(BOOST_MSVC, <= 1300) || BOOST_WORKAROUND(BOOST_INTEL_WIN, <= 900) |
---|
| 105 | () |
---|
| 106 | #endif |
---|
| 107 | ; |
---|
| 108 | std::cout << py.hello() << std::endl; |
---|
| 109 | } |
---|
| 110 | |
---|
| 111 | void |
---|
| 112 | test_tutorial() |
---|
| 113 | { |
---|
| 114 | using namespace boost::python; |
---|
| 115 | |
---|
| 116 | object main_module(( |
---|
| 117 | handle<>(borrowed(PyImport_AddModule("__main__"))))); |
---|
| 118 | |
---|
| 119 | object main_namespace = main_module.attr("__dict__"); |
---|
| 120 | |
---|
| 121 | handle<> ignored((PyRun_String( |
---|
| 122 | |
---|
| 123 | "hello = file('hello.txt', 'w')\n" |
---|
| 124 | "hello.write('Hello world!')\n" |
---|
| 125 | "hello.close()" |
---|
| 126 | |
---|
| 127 | , Py_file_input |
---|
| 128 | , main_namespace.ptr() |
---|
| 129 | , main_namespace.ptr()) |
---|
| 130 | )); |
---|
| 131 | } |
---|
| 132 | |
---|
| 133 | void |
---|
| 134 | test_tutorial2() |
---|
| 135 | { |
---|
| 136 | using namespace boost::python; |
---|
| 137 | |
---|
| 138 | object main_module(( |
---|
| 139 | handle<>(borrowed(PyImport_AddModule("__main__"))))); |
---|
| 140 | |
---|
| 141 | object main_namespace = main_module.attr("__dict__"); |
---|
| 142 | |
---|
| 143 | handle<> ignored((PyRun_String( |
---|
| 144 | |
---|
| 145 | "result = 5 ** 2" |
---|
| 146 | |
---|
| 147 | , Py_file_input |
---|
| 148 | , main_namespace.ptr() |
---|
| 149 | , main_namespace.ptr()) |
---|
| 150 | )); |
---|
| 151 | |
---|
| 152 | int five_squared = extract<int>(main_namespace["result"]); |
---|
| 153 | assert(five_squared == 25); |
---|
| 154 | |
---|
| 155 | object result((handle<>( |
---|
| 156 | PyRun_String("5 ** 2" |
---|
| 157 | , Py_eval_input |
---|
| 158 | , main_namespace.ptr() |
---|
| 159 | , main_namespace.ptr())) |
---|
| 160 | )); |
---|
| 161 | |
---|
| 162 | int five_squared2 = extract<int>(result); |
---|
| 163 | assert(five_squared2 == 25); |
---|
| 164 | } |
---|
| 165 | |
---|
| 166 | int main() |
---|
| 167 | { |
---|
| 168 | // Initialize the interpreter |
---|
| 169 | Py_Initialize(); |
---|
| 170 | |
---|
| 171 | if (python::handle_exception(test)) |
---|
| 172 | { |
---|
| 173 | if (PyErr_Occurred()) |
---|
| 174 | PyErr_Print(); |
---|
| 175 | return 1; |
---|
| 176 | } |
---|
| 177 | |
---|
| 178 | if (python::handle_exception(test_tutorial)) |
---|
| 179 | { |
---|
| 180 | if (PyErr_Occurred()) |
---|
| 181 | PyErr_Print(); |
---|
| 182 | return 1; |
---|
| 183 | } |
---|
| 184 | |
---|
| 185 | if (python::handle_exception(test_tutorial2)) |
---|
| 186 | { |
---|
| 187 | if (PyErr_Occurred()) |
---|
| 188 | PyErr_Print(); |
---|
| 189 | return 1; |
---|
| 190 | } |
---|
| 191 | |
---|
| 192 | // Boost.Python doesn't support Py_Finalize yet. |
---|
| 193 | // Py_Finalize(); |
---|
| 194 | return 0; |
---|
| 195 | } |
---|
| 196 | #include "module_tail.cpp" |
---|