When using `method_adaptor` (usually implicitly via a `cl.def("f",
&D::f)`) a compilation failure results if `f` is actually a method of
an inaccessible base class made public via `using`, such as:
class B { public: void f() {} };
class D : private B { public: using B::f; };
pybind deduces `&D::f` as a `B` member function pointer. Since the base
class is inaccessible, the cast in `method_adaptor` from a base class
member function pointer to derived class member function pointer isn't
valid, and a cast failure results.
This was sort of a regression in 2.2, which introduced `method_adaptor`
to do the expected thing when the base class *is* accessible. It wasn't
actually something that *worked* in 2.1, though: you wouldn't get a
compile-time failure, but the method was not callable (because the `D *`
couldn't be cast to a `B *` because of the access restriction). As a
result, you'd simply get a run-time failure if you ever tried to call
the function (this is what #855 fixed).
Thus the change in 2.2 essentially promoted a run-time failure to a
compile-time failure, so isn't really a regression.
This commit simply adds a `static_assert` with an accessible-base-class
check so that, rather than just a cryptic cast failure, you get
something more informative (along with a suggestion for a workaround).
The workaround is to use a lambda, e.g.:
class Derived : private Base {
public:
using Base::f;
};
// In binding code:
//cl.def("f", &Derived::f); // fails: &Derived::f is actually a base
// class member function pointer
cl.def("f", [](Derived &self) { return self.f(); });
This is a bit of a nuissance (especially if there are a bunch of
arguments to forward), but I don't really see another solution.
Fixes#1124
This changes the caster to return a reference to a (new) local `CharT`
type caster member so that binding lvalue-reference char arguments
works (currently it results in a compilation failure).
Fixes#1116
This also matches the Eigen example for the row-major case.
This also enhances one of the tests to trigger a failure (and fixes it in the PR). (This isn't really a flaw in pybind itself, but rather fixes wrong code in the test code and docs).
`type_descr` is now applied only to the final signature so that it only
marks the argument types, but not nested types (e.g. for tuples) or
return types.
MSCV does not allow `&typeid(T)` in constexpr contexts, but the string
part of the type signature can still be constexpr. In order to avoid
`typeid` as long as possible, `descr` is modified to collect type
information as template parameters instead of constexpr `typeid`.
The actual `std::type_info` pointers are only collected in the end,
as a `constexpr` (gcc/clang) or regular (MSVC) function call.
Not only does it significantly reduce binary size on MSVC, gcc/clang
benefit a little bit as well, since they can skip some intermediate
`std::type_info*` arrays.
The current C++14 constexpr signatures don't require relaxed constexpr,
but only `auto` return type deduction. To get around this in C++11,
the type caster's `name()` static member functions are turned into
`static constexpr auto` variables.
When Travis changes their default Python 3.x, it breaks any hardcoded
version selection. Fix: make pyenv activate everything (2.7, 3.x) and
use whichever Python 3.x is on by default.
[skip appveyor]
* Expand documentation to include explicit example of py::module::import
where one would expect it.
* Describe how to use unbound and bound methods to class Python classes.
[skip ci]
E.g. trying to convert a `list` to a `std::vector<int>` without
including <pybind11/stl.h> will now raise an error with a note that
suggests checking the headers.
The note is only appended if `std::` is found in the function
signature. This should only be the case when a header is missing.
E.g. when stl.h is included, the signature would contain `List[int]`
instead of `std::vector<int>` while using stl_bind.h would produce
something like `MyVector`. Similarly for `std::map`/`Dict`, `complex`,
`std::function`/`Callable`, etc.
There's a possibility for false positives, but it's pretty low.
To avoid an ODR violation in the test suite while testing
both `stl.h` and `std_bind.h` with `std::vector<bool>`,
the `py::bind_vector<std::vector<bool>>` test is moved to
the secondary module (which does not include `stl.h`).
* Update Python 3 osx image to xcode8.3 to speed up brew install.
The Python 2 osx image remains xcode7.3.
* Have one osx config run in debug mode to improve coverage.
* Only run CMake build tests on two configs to speed up overall build.
The CMake tests take ~30 seconds on each configuration, but we really
only need to them to run on two: one on Linux and one on macOS. This
mirrors the recent change on AppVeyor.
* Merge the style/docs/pip tests with the barebones build.
* Merge 32-bit and CMake install configurations.
This removes clang 3.9 from testing, but there are already 3 other clang
versions being tested on Travis and the new xcode8.3 image should be
close to clang 3.9.
[skip appveyor]
PR #880 changed the implementation of keep_alive to avoid weak
references when the nurse is pybind11-registered, but the documentation
didn't get updated to match.
There are two separate additions:
1. `py::hash(obj)` is equivalent to the Python `hash(obj)`.
2. `.def(hash(py::self))` registers the hash function defined by
`std::hash<T>` as the Python hash function.
The lookup of the `self` type and value pointer are moved out of
template code and into `dispatcher`. This brings down the binary
size of constructors back to the level of the old placement-new
approach. (It also avoids a second lookup for `init_instance`.)
With this implementation, mixing old- and new-style constructors
in the same overload set may result in some runtime overhead for
temporary allocations/deallocations, but this should be fine as
old style constructors are phased out.
