ああ、私はあなたの質問を誤解したようです。まあ、反対方向に行くのはそれほど違いはありません。これは、探している関数の (少なくとも最初の) はずです (ただし、完全にテストしていないため、バグに注意してください)。
// Returns a new reference
PyObject *ObjcToPyObject(id object)
{
if (object == nil) {
// This technically doesn't need to be an extra case,
// but you may want to differentiate it for error checking
return NULL;
} else if ([object isKindOfClass:[NSString class]]) {
return PyString_FromString([object UTF8String]);
} else if ([object isKindOfClass:[NSNumber class]]) {
// You could probably do some extra checking here if you need to
// with the -objCType method.
return PyLong_FromLong([object longValue]);
} else if ([object isKindOfClass:[NSArray class]]) {
// You may want to differentiate between NSArray (analagous to tuples)
// and NSMutableArray (analagous to lists) here.
Py_ssize_t i, len = [object count];
PyObject *list = PyList_New(len);
for (i = 0; i < len; ++i) {
PyObject *item = ObjcToPyObject([object objectAtIndex:i]);
NSCAssert(item != NULL, @"Can't add NULL item to Python List");
// Note that PyList_SetItem() "steals" the reference to the passed item.
// (i.e., you do not need to release it)
PyList_SetItem(list, i, item);
}
return list;
} else if ([object isKindOfClass:[NSDictionary class]]) {
PyObject *dict = PyDict_New();
for (id key in object) {
PyObject *pyKey = ObjcToPyObject(key);
NSCAssert(pyKey != NULL, @"Can't add NULL key to Python Dictionary");
PyObject *pyItem = ObjcToPyObject([object objectForKey:key]);
NSCAssert(pyItem != NULL, @"Can't add NULL item to Python Dictionary");
PyDict_SetItem(dict, pyKey, pyItem);
Py_DECREF(pyKey);
Py_DECREF(pyItem);
}
return dict;
} else {
NSLog(@"ObjcToPyObject() could not convert Obj-C object to PyObject.");
return NULL;
}
}
Python/C API リファレンス マニュアルをまだ読んでいない場合は、こちらもご覧になることをお勧めします。