The custom exception handling added in PR #273 is robust, but is overly
complex for declaring the most common simple C++ -> Python exception
mapping that needs only to copy `what()`. This add a simpler
`py::register_exception<CppExp>(module, "PyExp");` function that greatly
simplifies the common basic case of translation of a simple CppException
into a simple PythonException, while not removing the more advanced
capabilities of defining custom exception handlers.
The current inheritance testing isn't sufficient to detect a cache
failure; the test added here breaks PR #390, which caches the
run-time-determined return type the first time a function is called,
then reuses that cached type even though the run-time type could be
different for a future call.
This adds a static local variable (in dead code unless actually needed)
in the overload code that is used for storage if the overload is for
some convert-by-value type (such as numeric values or std::string).
This has limitations (as written up in the advanced doc), but is better
than simply not being able to overload reference or pointer methods.
This clears the Python error at the error_already_set throw site, thus
allowing Python calls to be made in destructors which are triggered by
the exception. This is preferable to the alternative, which would be
guarding every Python API call with an error_scope.
This effectively flips the behavior of error_already_set. Previously,
it was assumed that the error stays in Python, so handling the exception
in C++ would require explicitly calling PyErr_Clear(), but nothing was
needed to propagate the error to Python. With this change, handling the
error in C++ does not require a PyErr_Clear() call, but propagating the
error to Python requires an explicit error_already_set::restore().
The change does not break old code which explicitly calls PyErr_Clear()
for cleanup, which should be the majority of user code. The need for an
explicit restore() call does break old code, but this should be mostly
confined to the library and not user code.
- Try to update and upgrade twice (with a brief pause between attempts)
to deal with occassional spurious server failures or repository race
conditions. Do the same for the main package install.
- Use dist-upgrade instead of upgrade for updating the image
- Add -q to the upgrade and install commands to make apt less verbose.
This commit adds support for forcing alias type initialization by
defining constructors with `py::init_alias<arg1, arg2>()` instead of
`py::init<arg1, arg2>()`. Currently py::init<> only results in Alias
initialization if the type is extended in python, or the given
arguments can't be used to construct the base type, but can be used to
construct the alias. py::init_alias<>, in contrast, always invokes the
constructor of the alias type.
It looks like this was already the intention of
`py::detail::init_alias`, which was forward-declared in
86d825f330, but was apparently never
finished: despite the existance of a .def method accepting it, the
`detail::init_alias` class isn't actually defined anywhere.
This commit completes the feature (or possibly repurposes it), allowing
declaration of classes that will always initialize the trampoline which
is (as I argued in #397) sometimes useful.
Switch count_t to use constexpr_sum (under non-MSVC), and then make
all_of_t/any_of_t use it instead of doing the sum itself.
For MSVC, count_t is still done using template recursion, but
all_of_t/any_of_t can also make use of it.
Type alias for alias classes with members didn't work properly: space
was only allocated for sizeof(type), but if we want to be able to put a
type_alias instance there, we need sizeof(type_alias), but
sizeof(type_alias) > sizeof(type) whenever type_alias has members.
The previous commit to address #392 triggers a compiler warning about
returning a reference to a local variable, which is *not* a false alarm:
the following:
py::cast<int &>(o)
(which happens internally in an overload declaration) really is
returning a reference to a local, because the cast operators for the
type_caster for numeric types returns a reference to its own member.
This commit adds a static_assert to make that a compilation failure
rather than returning a reference into about-to-be-freed memory.
Incidentally, this is also a fix for #219, which is exactly the same
issue: we can't reference numeric primitives that are cast from
wrappers around python numeric types.
This allows a slightly cleaner base type specification of:
py::class_<Type, Base>("Type")
as an alternative to
py::class_<Type>("Type", py::base<Base>())
As with the other template parameters, the order relative to the holder
or trampoline types doesn't matter.
This also includes a compile-time assertion failure if attempting to
specify more than one base class (but is easily extendible to support
multiple inheritance, someday, by updating the class_selector::set_bases
function to set multiple bases).
With this change both C++ and Python write to sys.stdout which resolves
the capture issues noted in #351. Therefore, the related workarounds are
removed.
The current pybind11::class_<Type, Holder, Trampoline> fixed template
ordering results in a requirement to repeat the Holder with its default
value (std::unique_ptr<Type>) argument, which is a little bit annoying:
it needs to be specified not because we want to override the default,
but rather because we need to specify the third argument.
This commit removes this limitation by making the class_ template take
the type name plus a parameter pack of options. It then extracts the
first valid holder type and the first subclass type for holder_type and
trampoline type_alias, respectively. (If unfound, both fall back to
their current defaults, `std::unique_ptr<type>` and `type`,
respectively). If any unmatched template arguments are provided, a
static assertion fails.
What this means is that you can specify or omit the arguments in any
order:
py::class_<A, PyA> c1(m, "A");
py::class_<B, PyB, std::shared_ptr<B>> c2(m, "B");
py::class_<C, std::shared_ptr<C>, PyB> c3(m, "C");
It also allows future class attributes (such as base types in the next
commit) to be passed as class template types rather than needing to use
a py::base<> wrapper.