In pure Python, it is relatively simple to define and use a metaclass. class Meta(type): def __new__(cls, name, bases, dict): x = super().__new__(cls, name, bases, dict) print("I’m called on class construction time!") return x class A(metaclass=Meta): pass class B(A): pass How do you define this metaclass from a Python C extension? Source: Python..
Category : python-extensions
I have a PyLongObject obj and I am debugging a segfault at the moment. Printing in one of my loops while (…) { … while (…) { printf("Py_SIZE(obj) is %zdn", Py_SIZE(obj)) } } Shows that the object’s size is changing , it goes up the more iterations there are (but not one every iteration). PyLongObject ..
There is a memory leak in my encode method. static const size_t _bits_per_digit = sizeof(digit) * CHAR_BIT; /** * Returns a Python int storing the bitstream of the Elias gamma encoded input list. */ static PyObject * encode(PyObject *self, PyObject *obj) { if (!PyList_Check(obj)) { PyErr_SetString(PyExc_TypeError, "Input to encode must be a list"); return NULL; ..
https://github.com/python/cpython/blob/master/Include/objimpl.h#L83 says PyObject_Realloc(p != NULL, 0) does not return NULL, or free the memory at p. PyObject_Realloc doesn’t free the memory. I’ve noticed a memory leak in my program which uses PyObject_Realloc every now and then. I tried to fix it using this: PyLongObject *new = (PyLongObject *) PyObject_Realloc(obj, new_size); if (new == NULL) { ..
When i write python code on my visual studio code editor i can’t find any warnings or errors. I installed python extension, I also change the version of that extension.. I also read many documentations of python extension and visual studio but can’t find any solution Here is the image… Source: Python..
Since Python 3 there’s no upper limit on the size of an int. I’d like to deal with huge ints of 150+ decimal digits. This is far larger than a unsigned long long is guaranteed to be, so I don’t think I can rely on PyLong_AsLongLong and manipulate that. How can I perform mathematical operations ..
msgpack includes an optional cython extension. Some users of the package want py3-none-any wheels of msgpack. I’m trying to figure out how to make it possible to build wheels both with and without the optional extension. Source: Python..
I would like to create a module that uses a non python aware C library and ctypes. According to this documentation about creating a C extension to python, I’m required to provide a module initialization function with the signature PyObject* PyInit_modulename(void). This looks like a significant complication compared to using the wrapper using ctypes that ..
I have a compiled a Python extension. The resulting binary mylib.so file can be imported in the Python script and works fine. Now I am wondering how to write the interface stub file mylib.pyi such, that pylint and the Python language server used in VS Code can use it? For now the native library is ..
I’m trying to create and distribute (with pip) a Python package that has Python code, and C++ code compiled to a .pyd file with Pybind11 (using Visual Studio 2019). I also want to include .pyi stub files, for VScode and other editors. I can’t find much documentation on doing this correctly. I’d like to be ..
Recent Comments