mirror of
https://github.com/slsdetectorgroup/slsDetectorPackage.git
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Hardcopy of pybind11 instead of using git submodules (#552)
* removed pybind as submodule * added hardcopy of pybind11 2.10.0 * rename pybind11 folder to avoid conflicts when changing branch Co-authored-by: Dhanya Thattil <dhanya.thattil@psi.ch>
This commit is contained in:
552
libs/pybind/docs/upgrade.rst
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552
libs/pybind/docs/upgrade.rst
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@ -0,0 +1,552 @@
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Upgrade guide
|
||||
#############
|
||||
|
||||
This is a companion guide to the :doc:`changelog`. While the changelog briefly
|
||||
lists all of the new features, improvements and bug fixes, this upgrade guide
|
||||
focuses only the subset which directly impacts your experience when upgrading
|
||||
to a new version. But it goes into more detail. This includes things like
|
||||
deprecated APIs and their replacements, build system changes, general code
|
||||
modernization and other useful information.
|
||||
|
||||
.. _upgrade-guide-2.9:
|
||||
|
||||
v2.9
|
||||
====
|
||||
|
||||
* Any usage of the recently added ``py::make_simple_namespace`` should be
|
||||
converted to using ``py::module_::import("types").attr("SimpleNamespace")``
|
||||
instead.
|
||||
|
||||
* The use of ``_`` in custom type casters can now be replaced with the more
|
||||
readable ``const_name`` instead. The old ``_`` shortcut has been retained
|
||||
unless it is being used as a macro (like for gettext).
|
||||
|
||||
|
||||
.. _upgrade-guide-2.7:
|
||||
|
||||
v2.7
|
||||
====
|
||||
|
||||
*Before* v2.7, ``py::str`` can hold ``PyUnicodeObject`` or ``PyBytesObject``,
|
||||
and ``py::isinstance<str>()`` is ``true`` for both ``py::str`` and
|
||||
``py::bytes``. Starting with v2.7, ``py::str`` exclusively holds
|
||||
``PyUnicodeObject`` (`#2409 <https://github.com/pybind/pybind11/pull/2409>`_),
|
||||
and ``py::isinstance<str>()`` is ``true`` only for ``py::str``. To help in
|
||||
the transition of user code, the ``PYBIND11_STR_LEGACY_PERMISSIVE`` macro
|
||||
is provided as an escape hatch to go back to the legacy behavior. This macro
|
||||
will be removed in future releases. Two types of required fixes are expected
|
||||
to be common:
|
||||
|
||||
* Accidental use of ``py::str`` instead of ``py::bytes``, masked by the legacy
|
||||
behavior. These are probably very easy to fix, by changing from
|
||||
``py::str`` to ``py::bytes``.
|
||||
|
||||
* Reliance on py::isinstance<str>(obj) being ``true`` for
|
||||
``py::bytes``. This is likely to be easy to fix in most cases by adding
|
||||
``|| py::isinstance<bytes>(obj)``, but a fix may be more involved, e.g. if
|
||||
``py::isinstance<T>`` appears in a template. Such situations will require
|
||||
careful review and custom fixes.
|
||||
|
||||
|
||||
.. _upgrade-guide-2.6:
|
||||
|
||||
v2.6
|
||||
====
|
||||
|
||||
Usage of the ``PYBIND11_OVERLOAD*`` macros and ``get_overload`` function should
|
||||
be replaced by ``PYBIND11_OVERRIDE*`` and ``get_override``. In the future, the
|
||||
old macros may be deprecated and removed.
|
||||
|
||||
``py::module`` has been renamed ``py::module_``, but a backward compatible
|
||||
typedef has been included. This change was to avoid a language change in C++20
|
||||
that requires unqualified ``module`` not be placed at the start of a logical
|
||||
line. Qualified usage is unaffected and the typedef will remain unless the
|
||||
C++ language rules change again.
|
||||
|
||||
The public constructors of ``py::module_`` have been deprecated. Use
|
||||
``PYBIND11_MODULE`` or ``module_::create_extension_module`` instead.
|
||||
|
||||
An error is now thrown when ``__init__`` is forgotten on subclasses. This was
|
||||
incorrect before, but was not checked. Add a call to ``__init__`` if it is
|
||||
missing.
|
||||
|
||||
A ``py::type_error`` is now thrown when casting to a subclass (like
|
||||
``py::bytes`` from ``py::object``) if the conversion is not valid. Make a valid
|
||||
conversion instead.
|
||||
|
||||
The undocumented ``h.get_type()`` method has been deprecated and replaced by
|
||||
``py::type::of(h)``.
|
||||
|
||||
Enums now have a ``__str__`` method pre-defined; if you want to override it,
|
||||
the simplest fix is to add the new ``py::prepend()`` tag when defining
|
||||
``"__str__"``.
|
||||
|
||||
If ``__eq__`` defined but not ``__hash__``, ``__hash__`` is now set to
|
||||
``None``, as in normal CPython. You should add ``__hash__`` if you intended the
|
||||
class to be hashable, possibly using the new ``py::hash`` shortcut.
|
||||
|
||||
The constructors for ``py::array`` now always take signed integers for size,
|
||||
for consistency. This may lead to compiler warnings on some systems. Cast to
|
||||
``py::ssize_t`` instead of ``std::size_t``.
|
||||
|
||||
The ``tools/clang`` submodule and ``tools/mkdoc.py`` have been moved to a
|
||||
standalone package, `pybind11-mkdoc`_. If you were using those tools, please
|
||||
use them via a pip install from the new location.
|
||||
|
||||
The ``pybind11`` package on PyPI no longer fills the wheel "headers" slot - if
|
||||
you were using the headers from this slot, they are available by requesting the
|
||||
``global`` extra, that is, ``pip install "pybind11[global]"``. (Most users will
|
||||
be unaffected, as the ``pybind11/include`` location is reported by ``python -m
|
||||
pybind11 --includes`` and ``pybind11.get_include()`` is still correct and has
|
||||
not changed since 2.5).
|
||||
|
||||
.. _pybind11-mkdoc: https://github.com/pybind/pybind11-mkdoc
|
||||
|
||||
CMake support:
|
||||
--------------
|
||||
|
||||
The minimum required version of CMake is now 3.4. Several details of the CMake
|
||||
support have been deprecated; warnings will be shown if you need to change
|
||||
something. The changes are:
|
||||
|
||||
* ``PYBIND11_CPP_STANDARD=<platform-flag>`` is deprecated, please use
|
||||
``CMAKE_CXX_STANDARD=<number>`` instead, or any other valid CMake CXX or CUDA
|
||||
standard selection method, like ``target_compile_features``.
|
||||
|
||||
* If you do not request a standard, pybind11 targets will compile with the
|
||||
compiler default, but not less than C++11, instead of forcing C++14 always.
|
||||
If you depend on the old behavior, please use ``set(CMAKE_CXX_STANDARD 14 CACHE STRING "")``
|
||||
instead.
|
||||
|
||||
* Direct ``pybind11::module`` usage should always be accompanied by at least
|
||||
``set(CMAKE_CXX_VISIBILITY_PRESET hidden)`` or similar - it used to try to
|
||||
manually force this compiler flag (but not correctly on all compilers or with
|
||||
CUDA).
|
||||
|
||||
* ``pybind11_add_module``'s ``SYSTEM`` argument is deprecated and does nothing;
|
||||
linking now behaves like other imported libraries consistently in both
|
||||
config and submodule mode, and behaves like a ``SYSTEM`` library by
|
||||
default.
|
||||
|
||||
* If ``PYTHON_EXECUTABLE`` is not set, virtual environments (``venv``,
|
||||
``virtualenv``, and ``conda``) are prioritized over the standard search
|
||||
(similar to the new FindPython mode).
|
||||
|
||||
In addition, the following changes may be of interest:
|
||||
|
||||
* ``CMAKE_INTERPROCEDURAL_OPTIMIZATION`` will be respected by
|
||||
``pybind11_add_module`` if set instead of linking to ``pybind11::lto`` or
|
||||
``pybind11::thin_lto``.
|
||||
|
||||
* Using ``find_package(Python COMPONENTS Interpreter Development)`` before
|
||||
pybind11 will cause pybind11 to use the new Python mechanisms instead of its
|
||||
own custom search, based on a patched version of classic ``FindPythonInterp``
|
||||
/ ``FindPythonLibs``. In the future, this may become the default. A recent
|
||||
(3.15+ or 3.18.2+) version of CMake is recommended.
|
||||
|
||||
|
||||
|
||||
v2.5
|
||||
====
|
||||
|
||||
The Python package now includes the headers as data in the package itself, as
|
||||
well as in the "headers" wheel slot. ``pybind11 --includes`` and
|
||||
``pybind11.get_include()`` report the new location, which is always correct
|
||||
regardless of how pybind11 was installed, making the old ``user=`` argument
|
||||
meaningless. If you are not using the function to get the location already, you
|
||||
are encouraged to switch to the package location.
|
||||
|
||||
|
||||
v2.2
|
||||
====
|
||||
|
||||
Deprecation of the ``PYBIND11_PLUGIN`` macro
|
||||
--------------------------------------------
|
||||
|
||||
``PYBIND11_MODULE`` is now the preferred way to create module entry points.
|
||||
The old macro emits a compile-time deprecation warning.
|
||||
|
||||
.. code-block:: cpp
|
||||
|
||||
// old
|
||||
PYBIND11_PLUGIN(example) {
|
||||
py::module m("example", "documentation string");
|
||||
|
||||
m.def("add", [](int a, int b) { return a + b; });
|
||||
|
||||
return m.ptr();
|
||||
}
|
||||
|
||||
// new
|
||||
PYBIND11_MODULE(example, m) {
|
||||
m.doc() = "documentation string"; // optional
|
||||
|
||||
m.def("add", [](int a, int b) { return a + b; });
|
||||
}
|
||||
|
||||
|
||||
New API for defining custom constructors and pickling functions
|
||||
---------------------------------------------------------------
|
||||
|
||||
The old placement-new custom constructors have been deprecated. The new approach
|
||||
uses ``py::init()`` and factory functions to greatly improve type safety.
|
||||
|
||||
Placement-new can be called accidentally with an incompatible type (without any
|
||||
compiler errors or warnings), or it can initialize the same object multiple times
|
||||
if not careful with the Python-side ``__init__`` calls. The new-style custom
|
||||
constructors prevent such mistakes. See :ref:`custom_constructors` for details.
|
||||
|
||||
.. code-block:: cpp
|
||||
|
||||
// old -- deprecated (runtime warning shown only in debug mode)
|
||||
py::class<Foo>(m, "Foo")
|
||||
.def("__init__", [](Foo &self, ...) {
|
||||
new (&self) Foo(...); // uses placement-new
|
||||
});
|
||||
|
||||
// new
|
||||
py::class<Foo>(m, "Foo")
|
||||
.def(py::init([](...) { // Note: no `self` argument
|
||||
return new Foo(...); // return by raw pointer
|
||||
// or: return std::make_unique<Foo>(...); // return by holder
|
||||
// or: return Foo(...); // return by value (move constructor)
|
||||
}));
|
||||
|
||||
Mirroring the custom constructor changes, ``py::pickle()`` is now the preferred
|
||||
way to get and set object state. See :ref:`pickling` for details.
|
||||
|
||||
.. code-block:: cpp
|
||||
|
||||
// old -- deprecated (runtime warning shown only in debug mode)
|
||||
py::class<Foo>(m, "Foo")
|
||||
...
|
||||
.def("__getstate__", [](const Foo &self) {
|
||||
return py::make_tuple(self.value1(), self.value2(), ...);
|
||||
})
|
||||
.def("__setstate__", [](Foo &self, py::tuple t) {
|
||||
new (&self) Foo(t[0].cast<std::string>(), ...);
|
||||
});
|
||||
|
||||
// new
|
||||
py::class<Foo>(m, "Foo")
|
||||
...
|
||||
.def(py::pickle(
|
||||
[](const Foo &self) { // __getstate__
|
||||
return py::make_tuple(self.value1(), self.value2(), ...); // unchanged
|
||||
},
|
||||
[](py::tuple t) { // __setstate__, note: no `self` argument
|
||||
return new Foo(t[0].cast<std::string>(), ...);
|
||||
// or: return std::make_unique<Foo>(...); // return by holder
|
||||
// or: return Foo(...); // return by value (move constructor)
|
||||
}
|
||||
));
|
||||
|
||||
For both the constructors and pickling, warnings are shown at module
|
||||
initialization time (on import, not when the functions are called).
|
||||
They're only visible when compiled in debug mode. Sample warning:
|
||||
|
||||
.. code-block:: none
|
||||
|
||||
pybind11-bound class 'mymodule.Foo' is using an old-style placement-new '__init__'
|
||||
which has been deprecated. See the upgrade guide in pybind11's docs.
|
||||
|
||||
|
||||
Stricter enforcement of hidden symbol visibility for pybind11 modules
|
||||
---------------------------------------------------------------------
|
||||
|
||||
pybind11 now tries to actively enforce hidden symbol visibility for modules.
|
||||
If you're using either one of pybind11's :doc:`CMake or Python build systems
|
||||
<compiling>` (the two example repositories) and you haven't been exporting any
|
||||
symbols, there's nothing to be concerned about. All the changes have been done
|
||||
transparently in the background. If you were building manually or relied on
|
||||
specific default visibility, read on.
|
||||
|
||||
Setting default symbol visibility to *hidden* has always been recommended for
|
||||
pybind11 (see :ref:`faq:symhidden`). On Linux and macOS, hidden symbol
|
||||
visibility (in conjunction with the ``strip`` utility) yields much smaller
|
||||
module binaries. `CPython's extension docs`_ also recommend hiding symbols
|
||||
by default, with the goal of avoiding symbol name clashes between modules.
|
||||
Starting with v2.2, pybind11 enforces this more strictly: (1) by declaring
|
||||
all symbols inside the ``pybind11`` namespace as hidden and (2) by including
|
||||
the ``-fvisibility=hidden`` flag on Linux and macOS (only for extension
|
||||
modules, not for embedding the interpreter).
|
||||
|
||||
.. _CPython's extension docs: https://docs.python.org/3/extending/extending.html#providing-a-c-api-for-an-extension-module
|
||||
|
||||
The namespace-scope hidden visibility is done automatically in pybind11's
|
||||
headers and it's generally transparent to users. It ensures that:
|
||||
|
||||
* Modules compiled with different pybind11 versions don't clash with each other.
|
||||
|
||||
* Some new features, like ``py::module_local`` bindings, can work as intended.
|
||||
|
||||
The ``-fvisibility=hidden`` flag applies the same visibility to user bindings
|
||||
outside of the ``pybind11`` namespace. It's now set automatic by pybind11's
|
||||
CMake and Python build systems, but this needs to be done manually by users
|
||||
of other build systems. Adding this flag:
|
||||
|
||||
* Minimizes the chances of symbol conflicts between modules. E.g. if two
|
||||
unrelated modules were statically linked to different (ABI-incompatible)
|
||||
versions of the same third-party library, a symbol clash would be likely
|
||||
(and would end with unpredictable results).
|
||||
|
||||
* Produces smaller binaries on Linux and macOS, as pointed out previously.
|
||||
|
||||
Within pybind11's CMake build system, ``pybind11_add_module`` has always been
|
||||
setting the ``-fvisibility=hidden`` flag in release mode. From now on, it's
|
||||
being applied unconditionally, even in debug mode and it can no longer be opted
|
||||
out of with the ``NO_EXTRAS`` option. The ``pybind11::module`` target now also
|
||||
adds this flag to its interface. The ``pybind11::embed`` target is unchanged.
|
||||
|
||||
The most significant change here is for the ``pybind11::module`` target. If you
|
||||
were previously relying on default visibility, i.e. if your Python module was
|
||||
doubling as a shared library with dependents, you'll need to either export
|
||||
symbols manually (recommended for cross-platform libraries) or factor out the
|
||||
shared library (and have the Python module link to it like the other
|
||||
dependents). As a temporary workaround, you can also restore default visibility
|
||||
using the CMake code below, but this is not recommended in the long run:
|
||||
|
||||
.. code-block:: cmake
|
||||
|
||||
target_link_libraries(mymodule PRIVATE pybind11::module)
|
||||
|
||||
add_library(restore_default_visibility INTERFACE)
|
||||
target_compile_options(restore_default_visibility INTERFACE -fvisibility=default)
|
||||
target_link_libraries(mymodule PRIVATE restore_default_visibility)
|
||||
|
||||
|
||||
Local STL container bindings
|
||||
----------------------------
|
||||
|
||||
Previous pybind11 versions could only bind types globally -- all pybind11
|
||||
modules, even unrelated ones, would have access to the same exported types.
|
||||
However, this would also result in a conflict if two modules exported the
|
||||
same C++ type, which is especially problematic for very common types, e.g.
|
||||
``std::vector<int>``. :ref:`module_local` were added to resolve this (see
|
||||
that section for a complete usage guide).
|
||||
|
||||
``py::class_`` still defaults to global bindings (because these types are
|
||||
usually unique across modules), however in order to avoid clashes of opaque
|
||||
types, ``py::bind_vector`` and ``py::bind_map`` will now bind STL containers
|
||||
as ``py::module_local`` if their elements are: builtins (``int``, ``float``,
|
||||
etc.), not bound using ``py::class_``, or bound as ``py::module_local``. For
|
||||
example, this change allows multiple modules to bind ``std::vector<int>``
|
||||
without causing conflicts. See :ref:`stl_bind` for more details.
|
||||
|
||||
When upgrading to this version, if you have multiple modules which depend on
|
||||
a single global binding of an STL container, note that all modules can still
|
||||
accept foreign ``py::module_local`` types in the direction of Python-to-C++.
|
||||
The locality only affects the C++-to-Python direction. If this is needed in
|
||||
multiple modules, you'll need to either:
|
||||
|
||||
* Add a copy of the same STL binding to all of the modules which need it.
|
||||
|
||||
* Restore the global status of that single binding by marking it
|
||||
``py::module_local(false)``.
|
||||
|
||||
The latter is an easy workaround, but in the long run it would be best to
|
||||
localize all common type bindings in order to avoid conflicts with
|
||||
third-party modules.
|
||||
|
||||
|
||||
Negative strides for Python buffer objects and numpy arrays
|
||||
-----------------------------------------------------------
|
||||
|
||||
Support for negative strides required changing the integer type from unsigned
|
||||
to signed in the interfaces of ``py::buffer_info`` and ``py::array``. If you
|
||||
have compiler warnings enabled, you may notice some new conversion warnings
|
||||
after upgrading. These can be resolved using ``static_cast``.
|
||||
|
||||
|
||||
Deprecation of some ``py::object`` APIs
|
||||
---------------------------------------
|
||||
|
||||
To compare ``py::object`` instances by pointer, you should now use
|
||||
``obj1.is(obj2)`` which is equivalent to ``obj1 is obj2`` in Python.
|
||||
Previously, pybind11 used ``operator==`` for this (``obj1 == obj2``), but
|
||||
that could be confusing and is now deprecated (so that it can eventually
|
||||
be replaced with proper rich object comparison in a future release).
|
||||
|
||||
For classes which inherit from ``py::object``, ``borrowed`` and ``stolen``
|
||||
were previously available as protected constructor tags. Now the types
|
||||
should be used directly instead: ``borrowed_t{}`` and ``stolen_t{}``
|
||||
(`#771 <https://github.com/pybind/pybind11/pull/771>`_).
|
||||
|
||||
|
||||
Stricter compile-time error checking
|
||||
------------------------------------
|
||||
|
||||
Some error checks have been moved from run time to compile time. Notably,
|
||||
automatic conversion of ``std::shared_ptr<T>`` is not possible when ``T`` is
|
||||
not directly registered with ``py::class_<T>`` (e.g. ``std::shared_ptr<int>``
|
||||
or ``std::shared_ptr<std::vector<T>>`` are not automatically convertible).
|
||||
Attempting to bind a function with such arguments now results in a compile-time
|
||||
error instead of waiting to fail at run time.
|
||||
|
||||
``py::init<...>()`` constructor definitions are also stricter and now prevent
|
||||
bindings which could cause unexpected behavior:
|
||||
|
||||
.. code-block:: cpp
|
||||
|
||||
struct Example {
|
||||
Example(int &);
|
||||
};
|
||||
|
||||
py::class_<Example>(m, "Example")
|
||||
.def(py::init<int &>()); // OK, exact match
|
||||
// .def(py::init<int>()); // compile-time error, mismatch
|
||||
|
||||
A non-``const`` lvalue reference is not allowed to bind to an rvalue. However,
|
||||
note that a constructor taking ``const T &`` can still be registered using
|
||||
``py::init<T>()`` because a ``const`` lvalue reference can bind to an rvalue.
|
||||
|
||||
v2.1
|
||||
====
|
||||
|
||||
Minimum compiler versions are enforced at compile time
|
||||
------------------------------------------------------
|
||||
|
||||
The minimums also apply to v2.0 but the check is now explicit and a compile-time
|
||||
error is raised if the compiler does not meet the requirements:
|
||||
|
||||
* GCC >= 4.8
|
||||
* clang >= 3.3 (appleclang >= 5.0)
|
||||
* MSVC >= 2015u3
|
||||
* Intel C++ >= 15.0
|
||||
|
||||
|
||||
The ``py::metaclass`` attribute is not required for static properties
|
||||
---------------------------------------------------------------------
|
||||
|
||||
Binding classes with static properties is now possible by default. The
|
||||
zero-parameter version of ``py::metaclass()`` is deprecated. However, a new
|
||||
one-parameter ``py::metaclass(python_type)`` version was added for rare
|
||||
cases when a custom metaclass is needed to override pybind11's default.
|
||||
|
||||
.. code-block:: cpp
|
||||
|
||||
// old -- emits a deprecation warning
|
||||
py::class_<Foo>(m, "Foo", py::metaclass())
|
||||
.def_property_readonly_static("foo", ...);
|
||||
|
||||
// new -- static properties work without the attribute
|
||||
py::class_<Foo>(m, "Foo")
|
||||
.def_property_readonly_static("foo", ...);
|
||||
|
||||
// new -- advanced feature, override pybind11's default metaclass
|
||||
py::class_<Bar>(m, "Bar", py::metaclass(custom_python_type))
|
||||
...
|
||||
|
||||
|
||||
v2.0
|
||||
====
|
||||
|
||||
Breaking changes in ``py::class_``
|
||||
----------------------------------
|
||||
|
||||
These changes were necessary to make type definitions in pybind11
|
||||
future-proof, to support PyPy via its ``cpyext`` mechanism (`#527
|
||||
<https://github.com/pybind/pybind11/pull/527>`_), and to improve efficiency
|
||||
(`rev. 86d825 <https://github.com/pybind/pybind11/commit/86d825>`_).
|
||||
|
||||
1. Declarations of types that provide access via the buffer protocol must
|
||||
now include the ``py::buffer_protocol()`` annotation as an argument to
|
||||
the ``py::class_`` constructor.
|
||||
|
||||
.. code-block:: cpp
|
||||
|
||||
py::class_<Matrix>("Matrix", py::buffer_protocol())
|
||||
.def(py::init<...>())
|
||||
.def_buffer(...);
|
||||
|
||||
2. Classes which include static properties (e.g. ``def_readwrite_static()``)
|
||||
must now include the ``py::metaclass()`` attribute. Note: this requirement
|
||||
has since been removed in v2.1. If you're upgrading from 1.x, it's
|
||||
recommended to skip directly to v2.1 or newer.
|
||||
|
||||
3. This version of pybind11 uses a redesigned mechanism for instantiating
|
||||
trampoline classes that are used to override virtual methods from within
|
||||
Python. This led to the following user-visible syntax change:
|
||||
|
||||
.. code-block:: cpp
|
||||
|
||||
// old v1.x syntax
|
||||
py::class_<TrampolineClass>("MyClass")
|
||||
.alias<MyClass>()
|
||||
...
|
||||
|
||||
// new v2.x syntax
|
||||
py::class_<MyClass, TrampolineClass>("MyClass")
|
||||
...
|
||||
|
||||
Importantly, both the original and the trampoline class are now specified
|
||||
as arguments to the ``py::class_`` template, and the ``alias<..>()`` call
|
||||
is gone. The new scheme has zero overhead in cases when Python doesn't
|
||||
override any functions of the underlying C++ class.
|
||||
`rev. 86d825 <https://github.com/pybind/pybind11/commit/86d825>`_.
|
||||
|
||||
The class type must be the first template argument given to ``py::class_``
|
||||
while the trampoline can be mixed in arbitrary order with other arguments
|
||||
(see the following section).
|
||||
|
||||
|
||||
Deprecation of the ``py::base<T>()`` attribute
|
||||
----------------------------------------------
|
||||
|
||||
``py::base<T>()`` was deprecated in favor of specifying ``T`` as a template
|
||||
argument to ``py::class_``. This new syntax also supports multiple inheritance.
|
||||
Note that, while the type being exported must be the first argument in the
|
||||
``py::class_<Class, ...>`` template, the order of the following types (bases,
|
||||
holder and/or trampoline) is not important.
|
||||
|
||||
.. code-block:: cpp
|
||||
|
||||
// old v1.x
|
||||
py::class_<Derived>("Derived", py::base<Base>());
|
||||
|
||||
// new v2.x
|
||||
py::class_<Derived, Base>("Derived");
|
||||
|
||||
// new -- multiple inheritance
|
||||
py::class_<Derived, Base1, Base2>("Derived");
|
||||
|
||||
// new -- apart from `Derived` the argument order can be arbitrary
|
||||
py::class_<Derived, Base1, Holder, Base2, Trampoline>("Derived");
|
||||
|
||||
|
||||
Out-of-the-box support for ``std::shared_ptr``
|
||||
----------------------------------------------
|
||||
|
||||
The relevant type caster is now built in, so it's no longer necessary to
|
||||
include a declaration of the form:
|
||||
|
||||
.. code-block:: cpp
|
||||
|
||||
PYBIND11_DECLARE_HOLDER_TYPE(T, std::shared_ptr<T>)
|
||||
|
||||
Continuing to do so won't cause an error or even a deprecation warning,
|
||||
but it's completely redundant.
|
||||
|
||||
|
||||
Deprecation of a few ``py::object`` APIs
|
||||
----------------------------------------
|
||||
|
||||
All of the old-style calls emit deprecation warnings.
|
||||
|
||||
+---------------------------------------+---------------------------------------------+
|
||||
| Old syntax | New syntax |
|
||||
+=======================================+=============================================+
|
||||
| ``obj.call(args...)`` | ``obj(args...)`` |
|
||||
+---------------------------------------+---------------------------------------------+
|
||||
| ``obj.str()`` | ``py::str(obj)`` |
|
||||
+---------------------------------------+---------------------------------------------+
|
||||
| ``auto l = py::list(obj); l.check()`` | ``py::isinstance<py::list>(obj)`` |
|
||||
+---------------------------------------+---------------------------------------------+
|
||||
| ``py::object(ptr, true)`` | ``py::reinterpret_borrow<py::object>(ptr)`` |
|
||||
+---------------------------------------+---------------------------------------------+
|
||||
| ``py::object(ptr, false)`` | ``py::reinterpret_steal<py::object>(ptr)`` |
|
||||
+---------------------------------------+---------------------------------------------+
|
||||
| ``if (obj.attr("foo"))`` | ``if (py::hasattr(obj, "foo"))`` |
|
||||
+---------------------------------------+---------------------------------------------+
|
||||
| ``if (obj["bar"])`` | ``if (obj.contains("bar"))`` |
|
||||
+---------------------------------------+---------------------------------------------+
|
Reference in New Issue
Block a user