| 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687 |
- // Copyright (C) 2025 Ford Motor Company
- // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
- #ifndef PYSIDE_CAPSULEMETHOD_P_H
- #define PYSIDE_CAPSULEMETHOD_P_H
- #include <sbkpython.h>
- extern "C"
- {
- /**
- * This code is needed to solve, in C++ and adhering to the stable API,
- * creating what are in effect lambda functions as instance methods on custom
- * types. The goal is to be able to add methods to a dynamic type. If the .rep
- * file defines a slot `mySlot`, it need to be added to the dynamic type. For
- * Source types, this should be an abstract method that raises a
- * NotImplementedError unless defined in the Python subclass. For Replica
- * types, this should include an implementation that forwards the request
- * through the underlying QRemoteObjectReplica instance.
- *
- * The stable API doesn't currently provide a way define a method that can
- * receive both the `self`, `args`, and runtime (but constant per method, i.e.,
- * lambda like) data using Py_tp_methods. Possibly post 3.13 when METH_METHOD is
- * part of the stable API. But for now, it is not.
- *
- * The solution is to create a custom descriptor
- * (https://docs.python.org/3/howto/descriptor.html) that can hold the runtime
- * data and then when called, will return a PyCFunction_New generated PyObject
- * that is passed both class instance `self` and the runtime data (a PyCapsule)
- * together as a tuple as a new `self` for the method. The static method
- * definition needs to expect and handle this, but when combined in C++, we can
- * define a single handler that receives both the original `self` of the instance
- * and the runtime capsule with data for handling.
- */
- /**
- * The CapsuleDescriptorData struct is what will be passed as the pseudo `self`
- * from a CapsuleMethod or CapsuleProperty to the associated handler method. The
- * handler method (which should look like a standard PyMethodDef method) should
- * parse it into the payload (the "lambda variables") and the actual instance
- * (the "self").
- */
- struct CapsuleDescriptorData
- {
- PyObject *self;
- PyObject *payload;
- };
- /**
- * The new type defining a descriptor that stores a PyCapsule. This is used to
- * store the runtime data, with the __get__ method returning a new Callable.
- */
- PyTypeObject *CapsuleMethod_TypeF(void);
- /**
- * The new type defining a descriptor that stores a PyCapsule. This is used to
- * store the runtime data, with the __get__ (and __set__ if isWritable) providing
- * property behavior.
- */
- PyTypeObject *CapsuleProperty_TypeF(bool isWritable);
- /**
- * Add a capsule method (a descriptor) to a type. This will create a new capsule
- * method descriptor and add it as an attribute to the type, using the given name.
- *
- * A single handle can then respond to what appear to be distinct methods on the
- * type, but using the runtime data (from the capsule) when handling each call.
- *
- * @param type The type to attach the created descriptor to.
- * @param method The method definition to associate with the descriptor.
- * The name of the method will be used as the attribute name.
- * @param capsule The capsule to store in the descriptor.
- * @return True if the descriptor was added successfully, false otherwise.
- */
- bool add_capsule_method_to_type(PyTypeObject *type, PyMethodDef *method,
- PyObject *capsule);
- /**
- * Make a new CapsuleProperty type.
- */
- PyObject *make_capsule_property(PyMethodDef *method, PyObject *capsule,
- bool isWritable = false);
- } // extern "C"
- #endif // PYSIDE_CAPSULEMETHOD_P_H
|