// (C) Copyright David Abrahams 2000. Permission to copy, use, modify, sell and // distribute this software is granted provided this copyright notice appears // in all copies. This software is provided "as is" without express or implied // warranty, and with no claim as to its suitability for any purpose. // // The author gratefully acknowleges the support of Dragon Systems, Inc., in // producing this work. #include "extclass_demo.h" #include "class_wrapper.h" #include // used for portability on broken compilers namespace extclass_demo { FooCallback::FooCallback(PyObject* self, int x) : Foo(x), m_self(self) { } int FooCallback::add_len(const char* x) const { // Try to call the "add_len" method on the corresponding Python object. return py::Callback::call_method(m_self, "add_len", x); } // A function which Python can call in case bar is not overridden from // Python. In true Python style, we use a free function taking an initial self // parameter. This function anywhere needn't be a static member of the callback // class. The only reason to do it this way is that Foo::add_len is private, and // FooCallback is already a friend of Foo. int FooCallback::default_add_len(const Foo* self, const char* x) { // Don't forget the Foo:: qualification, or you'll get an infinite // recursion! return self->Foo::add_len(x); } // Since Foo::pure() is pure virtual, we don't need a corresponding // default_pure(). A failure to override it in Python will result in an // exception at runtime when pure() is called. const char* FooCallback::pure() const { return py::Callback::call_method(m_self, "pure"); } // The initializer for ExtensionClass is entirely optional. It // only affects the way that instances of this class _print_ in Python. If you // need an absolutely predictable name for the type, use the // initializer. Otherwise, C++ will generate an implementation-dependent // representation of the type name, usually something like "class // extclass_demo::Foo". I've supplied it here in part so that I can write // doctests that exactly anticipate the generated error messages. Foo::PythonClass::PythonClass() : py::ExtensionClass("Foo") // optional { def(py::Constructor()); def(&Foo::mumble, "mumble"); def(&Foo::set, "set"); def(&Foo::call_pure, "call_pure"); def(&Foo::call_add_len, "call_add_len"); // This is the way we add a virtual function that has a default implementation. def(&Foo::add_len, "add_len", &FooCallback::default_add_len); // Since pure() is pure virtual, we are leaving it undefined. } BarPythonClass::BarPythonClass() : py::ExtensionClass("Bar") // optional { def(py::Constructor()); def(&Bar::first, "first"); def(&Bar::second, "second"); def(&Bar::pass_baz, "pass_baz"); } BazPythonClass::BazPythonClass() : py::ExtensionClass("Baz") // optional { def(py::Constructor()); def(&Baz::pass_bar, "pass_bar"); def(&Baz::clone, "clone"); def(&Baz::create_foo, "create_foo"); def(&Baz::get_foo_value, "get_foo_value"); def(&Baz::eat_baz, "eat_baz"); } StringMapPythonClass::StringMapPythonClass() : py::ExtensionClass("StringMap") { def(py::Constructor()); def(&StringMap::size, "__len__"); def(&get_item, "__getitem__"); def(&set_item, "__setitem__"); def(&del_item, "__delitem__"); } int get_first(const IntPair& p) { return p.first; } void set_first(IntPair& p, int value) { p.first = -value; } void del_first(const IntPair&) { PyErr_SetString(PyExc_AttributeError, "first can't be deleted!"); throw py::ErrorAlreadySet(); } IntPairPythonClass::IntPairPythonClass() : py::ExtensionClass("IntPair") { def(py::Constructor()); def(&getattr, "__getattr__"); def(&setattr, "__setattr__"); def(&delattr, "__delattr__"); def(&get_first, "__getattr__first__"); def(&set_first, "__setattr__first__"); def(&del_first, "__delattr__first__"); } void IntPairPythonClass::setattr(IntPair& x, const std::string& name, int value) { if (name == "second") { x.second = value; } else { PyErr_SetString(PyExc_AttributeError, name.c_str()); throw py::ErrorAlreadySet(); } } void IntPairPythonClass::delattr(IntPair&, const char*) { PyErr_SetString(PyExc_AttributeError, "Attributes can't be deleted!"); throw py::ErrorAlreadySet(); } int IntPairPythonClass::getattr(const IntPair& p, const std::string& s) { if (s == "second") { return p.second; } else { PyErr_SetString(PyExc_AttributeError, s.c_str()); throw py::ErrorAlreadySet(); } #if defined(__MWERKS__) && __MWERKS__ <= 0x6000 return 0; #endif } namespace { namespace file_local { void throw_key_error_if_end(const StringMap& m, StringMap::const_iterator p, std::size_t key) { if (p == m.end()) { PyErr_SetObject(PyExc_KeyError, py::converters::to_python(key)); throw py::ErrorAlreadySet(); } } }} // namespace ::file_local const std::string& StringMapPythonClass::get_item(const StringMap& m, std::size_t key) { const StringMap::const_iterator p = m.find(key); file_local::throw_key_error_if_end(m, p, key); return p->second; } void StringMapPythonClass::set_item(StringMap& m, std::size_t key, const std::string& value) { m[key] = value; } void StringMapPythonClass::del_item(StringMap& m, std::size_t key) { const StringMap::iterator p = m.find(key); file_local::throw_key_error_if_end(m, p, key); m.erase(p); } // // Show that polymorphism can work. a DerivedFromFoo object will be passed to // Python in a smart pointer object. // class DerivedFromFoo : public Foo { public: DerivedFromFoo(int x) : Foo(x) {} private: const char* pure() const { return "this was never pure!"; } int add_len(const char*) const { return 1000; } }; // // function implementations // IntPair make_pair(int x, int y) { return std::make_pair(x, y); } const char* Foo::mumble() { return "mumble"; } void Foo::set(long x) { m_x = x; } const char* Foo::call_pure() { return this->pure(); } int Foo::call_add_len(const char* s) const { return this->add_len(s); } int Foo::add_len(const char* s) const // sum the held value and the length of s { return PY_CSTD_::strlen(s) + static_cast(m_x); } boost::shared_ptr Baz::create_foo() { return boost::shared_ptr(new DerivedFromFoo(0)); } // We can accept smart pointer parameters int Baz::get_foo_value(boost::shared_ptr foo) { return foo->call_add_len(""); } // Show what happens in python when we take ownership from an auto_ptr void Baz::eat_baz(std::auto_ptr baz) { baz->clone(); // just do something to show that it is valid. } Baz Bar::pass_baz(Baz b) { return b; } std::string stringpair_repr(const StringPair& sp) { return "('" + sp.first + "', '" + sp.second + "')"; } int stringpair_compare(const StringPair& sp1, const StringPair& sp2) { return sp1 < sp2 ? -1 : sp2 < sp1 ? 1 : 0; } py::String range_str(const Range& r) { char buf[200]; sprintf(buf, "(%d, %d)", r.m_start, r.m_finish); return py::String(buf); } int range_compare(const Range& r1, const Range& r2) { int d = r1.m_start - r2.m_start; if (d == 0) d = r1.m_finish - r2.m_finish; return d; } long range_hash(const Range& r) { return r.m_start * 123 + r.m_finish; } void init_module(py::Module& m) { m.add(new Foo::PythonClass); m.add(new BarPythonClass); m.add(new BazPythonClass); m.add(new StringMapPythonClass); m.add(new IntPairPythonClass); m.def(make_pair, "make_pair"); m.add(new CompareIntPairPythonClass); py::ClassWrapper string_pair(m, "StringPair"); string_pair.def(py::Constructor()); string_pair.def_readonly(&StringPair::first, "first"); string_pair.def_read_write(&StringPair::second, "second"); string_pair.def(&stringpair_repr, "__repr__"); string_pair.def(&stringpair_compare, "__cmp__"); m.def(first_string, "first_string"); m.def(second_string, "second_string"); py::ClassWrapper range(m, "Range"); range.def(py::Constructor()); range.def(py::Constructor()); range.def((void (Range::*)(std::size_t))&Range::length, "__len__"); range.def((std::size_t (Range::*)() const)&Range::length, "__len__"); range.def(&Range::operator[], "__getitem__"); range.def(&Range::slice, "__getslice__"); range.def(&range_str, "__str__"); range.def(&range_compare, "__cmp__"); range.def(&range_hash, "__hash__"); range.def_readonly(&Range::m_start, "start"); range.def_readonly(&Range::m_finish, "finish"); } void init_module() { py::Module demo("demo"); init_module(demo); // Just for giggles, add a raw metaclass. demo.add(new py::MetaClass); } extern "C" #ifdef _WIN32 __declspec(dllexport) #endif void initdemo() { try { extclass_demo::init_module(); } catch(...) { py::handle_exception(); } // Need a way to report other errors here } CompareIntPairPythonClass::CompareIntPairPythonClass() : py::ExtensionClass("CompareIntPair") { def(py::Constructor()); def(&CompareIntPair::operator(), "__call__"); } } // namespace extclass_demo #if defined(_WIN32) # include extern "C" BOOL WINAPI DllMain ( HINSTANCE hInst, DWORD wDataSeg, LPVOID lpvReserved ); # ifdef PY_COMPILER_IS_MSVC extern "C" void structured_exception_translator(unsigned int, EXCEPTION_POINTERS*) { throw; } # endif BOOL WINAPI DllMain( HINSTANCE, //hDllInst DWORD fdwReason, LPVOID // lpvReserved ) { # ifdef PY_COMPILER_IS_MSVC _set_se_translator(structured_exception_translator); #endif return 1; (void)fdwReason; // warning suppression. } #endif // _WIN32