/
pybind11.h
1875 lines (1641 loc) · 82.6 KB
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pybind11.h
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/*
pybind11/pybind11.h: Main header file of the C++11 python
binding generator library
Copyright (c) 2016 Wenzel Jakob <wenzel.jakob@epfl.ch>
All rights reserved. Use of this source code is governed by a
BSD-style license that can be found in the LICENSE file.
*/
#pragma once
#if defined(_MSC_VER)
# pragma warning(push)
# pragma warning(disable: 4100) // warning C4100: Unreferenced formal parameter
# pragma warning(disable: 4127) // warning C4127: Conditional expression is constant
# pragma warning(disable: 4512) // warning C4512: Assignment operator was implicitly defined as deleted
# pragma warning(disable: 4800) // warning C4800: 'int': forcing value to bool 'true' or 'false' (performance warning)
# pragma warning(disable: 4996) // warning C4996: The POSIX name for this item is deprecated. Instead, use the ISO C and C++ conformant name
# pragma warning(disable: 4702) // warning C4702: unreachable code
# pragma warning(disable: 4522) // warning C4522: multiple assignment operators specified
#elif defined(__INTEL_COMPILER)
# pragma warning(push)
# pragma warning(disable: 68) // integer conversion resulted in a change of sign
# pragma warning(disable: 186) // pointless comparison of unsigned integer with zero
# pragma warning(disable: 878) // incompatible exception specifications
# pragma warning(disable: 1334) // the "template" keyword used for syntactic disambiguation may only be used within a template
# pragma warning(disable: 1682) // implicit conversion of a 64-bit integral type to a smaller integral type (potential portability problem)
# pragma warning(disable: 1875) // offsetof applied to non-POD (Plain Old Data) types is nonstandard
# pragma warning(disable: 2196) // warning #2196: routine is both "inline" and "noinline"
#elif defined(__GNUG__) && !defined(__clang__)
# pragma GCC diagnostic push
# pragma GCC diagnostic ignored "-Wunused-but-set-parameter"
# pragma GCC diagnostic ignored "-Wunused-but-set-variable"
# pragma GCC diagnostic ignored "-Wmissing-field-initializers"
# pragma GCC diagnostic ignored "-Wstrict-aliasing"
# pragma GCC diagnostic ignored "-Wattributes"
# if __GNUC__ >= 7
# pragma GCC diagnostic ignored "-Wnoexcept-type"
# endif
#endif
#include "attr.h"
#include "options.h"
#include "detail/class.h"
#include "detail/init.h"
NAMESPACE_BEGIN(PYBIND11_NAMESPACE)
/// Wraps an arbitrary C++ function/method/lambda function/.. into a callable Python object
class cpp_function : public function {
public:
cpp_function() { }
/// Construct a cpp_function from a vanilla function pointer
template <typename Return, typename... Args, typename... Extra>
cpp_function(Return (*f)(Args...), const Extra&... extra) {
initialize(f, f, extra...);
}
/// Construct a cpp_function from a lambda function (possibly with internal state)
template <typename Func, typename... Extra,
typename = detail::enable_if_t<detail::is_lambda<Func>::value>>
cpp_function(Func &&f, const Extra&... extra) {
initialize(std::forward<Func>(f),
(detail::function_signature_t<Func> *) nullptr, extra...);
}
/// Construct a cpp_function from a class method (non-const)
template <typename Return, typename Class, typename... Arg, typename... Extra>
cpp_function(Return (Class::*f)(Arg...), const Extra&... extra) {
initialize([f](Class *c, Arg... args) -> Return { return (c->*f)(args...); },
(Return (*) (Class *, Arg...)) nullptr, extra...);
}
/// Construct a cpp_function from a class method (const)
template <typename Return, typename Class, typename... Arg, typename... Extra>
cpp_function(Return (Class::*f)(Arg...) const, const Extra&... extra) {
initialize([f](const Class *c, Arg... args) -> Return { return (c->*f)(args...); },
(Return (*)(const Class *, Arg ...)) nullptr, extra...);
}
/// Return the function name
object name() const { return attr("__name__"); }
protected:
/// Space optimization: don't inline this frequently instantiated fragment
PYBIND11_NOINLINE detail::function_record *make_function_record() {
return new detail::function_record();
}
/// Special internal constructor for functors, lambda functions, etc.
template <typename Func, typename Return, typename... Args, typename... Extra>
void initialize(Func &&f, Return (*)(Args...), const Extra&... extra) {
struct capture { detail::remove_reference_t<Func> f; };
/* Store the function including any extra state it might have (e.g. a lambda capture object) */
auto rec = make_function_record();
/* Store the capture object directly in the function record if there is enough space */
if (sizeof(capture) <= sizeof(rec->data)) {
/* Without these pragmas, GCC warns that there might not be
enough space to use the placement new operator. However, the
'if' statement above ensures that this is the case. */
#if defined(__GNUG__) && !defined(__clang__) && __GNUC__ >= 6
# pragma GCC diagnostic push
# pragma GCC diagnostic ignored "-Wplacement-new"
#endif
new ((capture *) &rec->data) capture { std::forward<Func>(f) };
#if defined(__GNUG__) && !defined(__clang__) && __GNUC__ >= 6
# pragma GCC diagnostic pop
#endif
if (!std::is_trivially_destructible<Func>::value)
rec->free_data = [](detail::function_record *r) { ((capture *) &r->data)->~capture(); };
} else {
rec->data[0] = new capture { std::forward<Func>(f) };
rec->free_data = [](detail::function_record *r) { delete ((capture *) r->data[0]); };
}
/* Type casters for the function arguments and return value */
using cast_in = detail::argument_loader<Args...>;
using cast_out = detail::make_caster<
detail::conditional_t<std::is_void<Return>::value, detail::void_type, Return>
>;
static_assert(detail::expected_num_args<Extra...>(sizeof...(Args), cast_in::has_args, cast_in::has_kwargs),
"The number of argument annotations does not match the number of function arguments");
/* Dispatch code which converts function arguments and performs the actual function call */
rec->impl = [](detail::function_call &call) -> handle {
cast_in args_converter;
/* Try to cast the function arguments into the C++ domain */
if (!args_converter.load_args(call))
return PYBIND11_TRY_NEXT_OVERLOAD;
/* Invoke call policy pre-call hook */
detail::process_attributes<Extra...>::precall(call);
/* Get a pointer to the capture object */
auto data = (sizeof(capture) <= sizeof(call.func.data)
? &call.func.data : call.func.data[0]);
capture *cap = const_cast<capture *>(reinterpret_cast<const capture *>(data));
/* Override policy for rvalues -- usually to enforce rvp::move on an rvalue */
const auto policy = detail::return_value_policy_override<Return>::policy(call.func.policy);
/* Function scope guard -- defaults to the compile-to-nothing `void_type` */
using Guard = detail::extract_guard_t<Extra...>;
/* Perform the function call */
handle result = cast_out::cast(
std::move(args_converter).template call<Return, Guard>(cap->f), policy, call.parent);
/* Invoke call policy post-call hook */
detail::process_attributes<Extra...>::postcall(call, result);
return result;
};
/* Process any user-provided function attributes */
detail::process_attributes<Extra...>::init(extra..., rec);
/* Generate a readable signature describing the function's arguments and return value types */
using detail::descr; using detail::_;
PYBIND11_DESCR signature = _("(") + cast_in::arg_names() + _(") -> ") + cast_out::name();
/* Register the function with Python from generic (non-templated) code */
initialize_generic(rec, signature.text(), signature.types(), sizeof...(Args));
if (cast_in::has_args) rec->has_args = true;
if (cast_in::has_kwargs) rec->has_kwargs = true;
/* Stash some additional information used by an important optimization in 'functional.h' */
using FunctionType = Return (*)(Args...);
constexpr bool is_function_ptr =
std::is_convertible<Func, FunctionType>::value &&
sizeof(capture) == sizeof(void *);
if (is_function_ptr) {
rec->is_stateless = true;
rec->data[1] = const_cast<void *>(reinterpret_cast<const void *>(&typeid(FunctionType)));
}
}
/// Register a function call with Python (generic non-templated code goes here)
void initialize_generic(detail::function_record *rec, const char *text,
const std::type_info *const *types, size_t args) {
/* Create copies of all referenced C-style strings */
rec->name = strdup(rec->name ? rec->name : "");
if (rec->doc) rec->doc = strdup(rec->doc);
for (auto &a: rec->args) {
if (a.name)
a.name = strdup(a.name);
if (a.descr)
a.descr = strdup(a.descr);
else if (a.value)
a.descr = strdup(a.value.attr("__repr__")().cast<std::string>().c_str());
}
rec->is_constructor = !strcmp(rec->name, "__init__") || !strcmp(rec->name, "__setstate__");
/* Generate a proper function signature */
std::string signature;
size_t type_depth = 0, char_index = 0, type_index = 0, arg_index = 0;
while (true) {
char c = text[char_index++];
if (c == '\0')
break;
if (c == '{') {
// Write arg name for everything except *args, **kwargs and return type.
if (type_depth == 0 && text[char_index] != '*' && arg_index < args) {
if (!rec->args.empty() && rec->args[arg_index].name) {
signature += rec->args[arg_index].name;
} else if (arg_index == 0 && rec->is_method) {
signature += "self";
} else {
signature += "arg" + std::to_string(arg_index - (rec->is_method ? 1 : 0));
}
signature += ": ";
}
++type_depth;
} else if (c == '}') {
--type_depth;
if (type_depth == 0) {
if (arg_index < rec->args.size() && rec->args[arg_index].descr) {
signature += "=";
signature += rec->args[arg_index].descr;
}
arg_index++;
}
} else if (c == '%') {
const std::type_info *t = types[type_index++];
if (!t)
pybind11_fail("Internal error while parsing type signature (1)");
if (auto tinfo = detail::get_type_info(*t)) {
#if defined(PYPY_VERSION)
signature += handle((PyObject *) tinfo->type)
.attr("__module__")
.cast<std::string>() + ".";
#endif
signature += tinfo->type->tp_name;
} else if (rec->is_constructor && arg_index == 0 && detail::same_type(typeid(handle), *t) && rec->scope) {
// A py::init(...) constructor takes `self` as a `handle`; rewrite it to the type
#if defined(PYPY_VERSION)
signature += rec->scope.attr("__module__").cast<std::string>() + ".";
#endif
signature += ((PyTypeObject *) rec->scope.ptr())->tp_name;
} else {
std::string tname(t->name());
detail::clean_type_id(tname);
signature += tname;
}
} else {
signature += c;
}
}
if (type_depth != 0 || types[type_index] != nullptr)
pybind11_fail("Internal error while parsing type signature (2)");
#if !defined(PYBIND11_CONSTEXPR_DESCR)
delete[] types;
delete[] text;
#endif
#if PY_MAJOR_VERSION < 3
if (strcmp(rec->name, "__next__") == 0) {
std::free(rec->name);
rec->name = strdup("next");
} else if (strcmp(rec->name, "__bool__") == 0) {
std::free(rec->name);
rec->name = strdup("__nonzero__");
}
#endif
rec->signature = strdup(signature.c_str());
rec->args.shrink_to_fit();
rec->nargs = (std::uint16_t) args;
if (rec->sibling && PYBIND11_INSTANCE_METHOD_CHECK(rec->sibling.ptr()))
rec->sibling = PYBIND11_INSTANCE_METHOD_GET_FUNCTION(rec->sibling.ptr());
detail::function_record *chain = nullptr, *chain_start = rec;
if (rec->sibling) {
if (PyCFunction_Check(rec->sibling.ptr())) {
auto rec_capsule = reinterpret_borrow<capsule>(PyCFunction_GET_SELF(rec->sibling.ptr()));
chain = (detail::function_record *) rec_capsule;
/* Never append a method to an overload chain of a parent class;
instead, hide the parent's overloads in this case */
if (!chain->scope.is(rec->scope))
chain = nullptr;
}
// Don't trigger for things like the default __init__, which are wrapper_descriptors that we are intentionally replacing
else if (!rec->sibling.is_none() && rec->name[0] != '_')
pybind11_fail("Cannot overload existing non-function object \"" + std::string(rec->name) +
"\" with a function of the same name");
}
if (!chain) {
/* No existing overload was found, create a new function object */
rec->def = new PyMethodDef();
std::memset(rec->def, 0, sizeof(PyMethodDef));
rec->def->ml_name = rec->name;
rec->def->ml_meth = reinterpret_cast<PyCFunction>(*dispatcher);
rec->def->ml_flags = METH_VARARGS | METH_KEYWORDS;
capsule rec_capsule(rec, [](void *ptr) {
destruct((detail::function_record *) ptr);
});
object scope_module;
if (rec->scope) {
if (hasattr(rec->scope, "__module__")) {
scope_module = rec->scope.attr("__module__");
} else if (hasattr(rec->scope, "__name__")) {
scope_module = rec->scope.attr("__name__");
}
}
m_ptr = PyCFunction_NewEx(rec->def, rec_capsule.ptr(), scope_module.ptr());
if (!m_ptr)
pybind11_fail("cpp_function::cpp_function(): Could not allocate function object");
} else {
/* Append at the end of the overload chain */
m_ptr = rec->sibling.ptr();
inc_ref();
chain_start = chain;
if (chain->is_method != rec->is_method)
pybind11_fail("overloading a method with both static and instance methods is not supported; "
#if defined(NDEBUG)
"compile in debug mode for more details"
#else
"error while attempting to bind " + std::string(rec->is_method ? "instance" : "static") + " method " +
std::string(pybind11::str(rec->scope.attr("__name__"))) + "." + std::string(rec->name) + signature
#endif
);
while (chain->next)
chain = chain->next;
chain->next = rec;
}
std::string signatures;
int index = 0;
/* Create a nice pydoc rec including all signatures and
docstrings of the functions in the overload chain */
if (chain && options::show_function_signatures()) {
// First a generic signature
signatures += rec->name;
signatures += "(*args, **kwargs)\n";
signatures += "Overloaded function.\n\n";
}
// Then specific overload signatures
bool first_user_def = true;
for (auto it = chain_start; it != nullptr; it = it->next) {
if (options::show_function_signatures()) {
if (index > 0) signatures += "\n";
if (chain)
signatures += std::to_string(++index) + ". ";
signatures += rec->name;
signatures += it->signature;
signatures += "\n";
}
if (it->doc && strlen(it->doc) > 0 && options::show_user_defined_docstrings()) {
// If we're appending another docstring, and aren't printing function signatures, we
// need to append a newline first:
if (!options::show_function_signatures()) {
if (first_user_def) first_user_def = false;
else signatures += "\n";
}
if (options::show_function_signatures()) signatures += "\n";
signatures += it->doc;
if (options::show_function_signatures()) signatures += "\n";
}
}
/* Install docstring */
PyCFunctionObject *func = (PyCFunctionObject *) m_ptr;
if (func->m_ml->ml_doc)
std::free(const_cast<char *>(func->m_ml->ml_doc));
func->m_ml->ml_doc = strdup(signatures.c_str());
if (rec->is_method) {
m_ptr = PYBIND11_INSTANCE_METHOD_NEW(m_ptr, rec->scope.ptr());
if (!m_ptr)
pybind11_fail("cpp_function::cpp_function(): Could not allocate instance method object");
Py_DECREF(func);
}
}
/// When a cpp_function is GCed, release any memory allocated by pybind11
static void destruct(detail::function_record *rec) {
while (rec) {
detail::function_record *next = rec->next;
if (rec->free_data)
rec->free_data(rec);
std::free((char *) rec->name);
std::free((char *) rec->doc);
std::free((char *) rec->signature);
for (auto &arg: rec->args) {
std::free(const_cast<char *>(arg.name));
std::free(const_cast<char *>(arg.descr));
arg.value.dec_ref();
}
if (rec->def) {
std::free(const_cast<char *>(rec->def->ml_doc));
delete rec->def;
}
delete rec;
rec = next;
}
}
/// Main dispatch logic for calls to functions bound using pybind11
static PyObject *dispatcher(PyObject *self, PyObject *args_in, PyObject *kwargs_in) {
using namespace detail;
/* Iterator over the list of potentially admissible overloads */
function_record *overloads = (function_record *) PyCapsule_GetPointer(self, nullptr),
*it = overloads;
/* Need to know how many arguments + keyword arguments there are to pick the right overload */
const size_t n_args_in = (size_t) PyTuple_GET_SIZE(args_in);
handle parent = n_args_in > 0 ? PyTuple_GET_ITEM(args_in, 0) : nullptr,
result = PYBIND11_TRY_NEXT_OVERLOAD;
try {
// We do this in two passes: in the first pass, we load arguments with `convert=false`;
// in the second, we allow conversion (except for arguments with an explicit
// py::arg().noconvert()). This lets us prefer calls without conversion, with
// conversion as a fallback.
std::vector<function_call> second_pass;
// However, if there are no overloads, we can just skip the no-convert pass entirely
const bool overloaded = it != nullptr && it->next != nullptr;
for (; it != nullptr; it = it->next) {
/* For each overload:
1. Copy all positional arguments we were given, also checking to make sure that
named positional arguments weren't *also* specified via kwarg.
2. If we weren't given enough, try to make up the omitted ones by checking
whether they were provided by a kwarg matching the `py::arg("name")` name. If
so, use it (and remove it from kwargs; if not, see if the function binding
provided a default that we can use.
3. Ensure that either all keyword arguments were "consumed", or that the function
takes a kwargs argument to accept unconsumed kwargs.
4. Any positional arguments still left get put into a tuple (for args), and any
leftover kwargs get put into a dict.
5. Pack everything into a vector; if we have py::args or py::kwargs, they are an
extra tuple or dict at the end of the positional arguments.
6. Call the function call dispatcher (function_record::impl)
If one of these fail, move on to the next overload and keep trying until we get a
result other than PYBIND11_TRY_NEXT_OVERLOAD.
*/
function_record &func = *it;
size_t pos_args = func.nargs; // Number of positional arguments that we need
if (func.has_args) --pos_args; // (but don't count py::args
if (func.has_kwargs) --pos_args; // or py::kwargs)
if (!func.has_args && n_args_in > pos_args)
continue; // Too many arguments for this overload
if (n_args_in < pos_args && func.args.size() < pos_args)
continue; // Not enough arguments given, and not enough defaults to fill in the blanks
function_call call(func, parent);
size_t args_to_copy = std::min(pos_args, n_args_in);
size_t args_copied = 0;
// 1. Copy any position arguments given.
bool bad_arg = false;
for (; args_copied < args_to_copy; ++args_copied) {
argument_record *arg_rec = args_copied < func.args.size() ? &func.args[args_copied] : nullptr;
if (kwargs_in && arg_rec && arg_rec->name && PyDict_GetItemString(kwargs_in, arg_rec->name)) {
bad_arg = true;
break;
}
handle arg(PyTuple_GET_ITEM(args_in, args_copied));
if (arg_rec && !arg_rec->none && arg.is_none()) {
bad_arg = true;
break;
}
call.args.push_back(arg);
call.args_convert.push_back(arg_rec ? arg_rec->convert : true);
}
if (bad_arg)
continue; // Maybe it was meant for another overload (issue #688)
// We'll need to copy this if we steal some kwargs for defaults
dict kwargs = reinterpret_borrow<dict>(kwargs_in);
// 2. Check kwargs and, failing that, defaults that may help complete the list
if (args_copied < pos_args) {
bool copied_kwargs = false;
for (; args_copied < pos_args; ++args_copied) {
const auto &arg = func.args[args_copied];
handle value;
if (kwargs_in && arg.name)
value = PyDict_GetItemString(kwargs.ptr(), arg.name);
if (value) {
// Consume a kwargs value
if (!copied_kwargs) {
kwargs = reinterpret_steal<dict>(PyDict_Copy(kwargs.ptr()));
copied_kwargs = true;
}
PyDict_DelItemString(kwargs.ptr(), arg.name);
} else if (arg.value) {
value = arg.value;
}
if (value) {
call.args.push_back(value);
call.args_convert.push_back(arg.convert);
}
else
break;
}
if (args_copied < pos_args)
continue; // Not enough arguments, defaults, or kwargs to fill the positional arguments
}
// 3. Check everything was consumed (unless we have a kwargs arg)
if (kwargs && kwargs.size() > 0 && !func.has_kwargs)
continue; // Unconsumed kwargs, but no py::kwargs argument to accept them
// 4a. If we have a py::args argument, create a new tuple with leftovers
tuple extra_args;
if (func.has_args) {
if (args_to_copy == 0) {
// We didn't copy out any position arguments from the args_in tuple, so we
// can reuse it directly without copying:
extra_args = reinterpret_borrow<tuple>(args_in);
} else if (args_copied >= n_args_in) {
extra_args = tuple(0);
} else {
size_t args_size = n_args_in - args_copied;
extra_args = tuple(args_size);
for (size_t i = 0; i < args_size; ++i) {
handle item = PyTuple_GET_ITEM(args_in, args_copied + i);
extra_args[i] = item.inc_ref().ptr();
}
}
call.args.push_back(extra_args);
call.args_convert.push_back(false);
}
// 4b. If we have a py::kwargs, pass on any remaining kwargs
if (func.has_kwargs) {
if (!kwargs.ptr())
kwargs = dict(); // If we didn't get one, send an empty one
call.args.push_back(kwargs);
call.args_convert.push_back(false);
}
// 5. Put everything in a vector. Not technically step 5, we've been building it
// in `call.args` all along.
#if !defined(NDEBUG)
if (call.args.size() != func.nargs || call.args_convert.size() != func.nargs)
pybind11_fail("Internal error: function call dispatcher inserted wrong number of arguments!");
#endif
std::vector<bool> second_pass_convert;
if (overloaded) {
// We're in the first no-convert pass, so swap out the conversion flags for a
// set of all-false flags. If the call fails, we'll swap the flags back in for
// the conversion-allowed call below.
second_pass_convert.resize(func.nargs, false);
call.args_convert.swap(second_pass_convert);
}
// 6. Call the function.
try {
loader_life_support guard{};
result = func.impl(call);
} catch (reference_cast_error &) {
result = PYBIND11_TRY_NEXT_OVERLOAD;
}
if (result.ptr() != PYBIND11_TRY_NEXT_OVERLOAD)
break;
if (overloaded) {
// The (overloaded) call failed; if the call has at least one argument that
// permits conversion (i.e. it hasn't been explicitly specified `.noconvert()`)
// then add this call to the list of second pass overloads to try.
for (size_t i = func.is_method ? 1 : 0; i < pos_args; i++) {
if (second_pass_convert[i]) {
// Found one: swap the converting flags back in and store the call for
// the second pass.
call.args_convert.swap(second_pass_convert);
second_pass.push_back(std::move(call));
break;
}
}
}
}
if (overloaded && !second_pass.empty() && result.ptr() == PYBIND11_TRY_NEXT_OVERLOAD) {
// The no-conversion pass finished without success, try again with conversion allowed
for (auto &call : second_pass) {
try {
loader_life_support guard{};
result = call.func.impl(call);
} catch (reference_cast_error &) {
result = PYBIND11_TRY_NEXT_OVERLOAD;
}
if (result.ptr() != PYBIND11_TRY_NEXT_OVERLOAD)
break;
}
}
} catch (error_already_set &e) {
e.restore();
return nullptr;
} catch (...) {
/* When an exception is caught, give each registered exception
translator a chance to translate it to a Python exception
in reverse order of registration.
A translator may choose to do one of the following:
- catch the exception and call PyErr_SetString or PyErr_SetObject
to set a standard (or custom) Python exception, or
- do nothing and let the exception fall through to the next translator, or
- delegate translation to the next translator by throwing a new type of exception. */
auto last_exception = std::current_exception();
auto ®istered_exception_translators = get_internals().registered_exception_translators;
for (auto& translator : registered_exception_translators) {
try {
translator(last_exception);
} catch (...) {
last_exception = std::current_exception();
continue;
}
return nullptr;
}
PyErr_SetString(PyExc_SystemError, "Exception escaped from default exception translator!");
return nullptr;
}
if (result.ptr() == PYBIND11_TRY_NEXT_OVERLOAD) {
if (overloads->is_operator)
return handle(Py_NotImplemented).inc_ref().ptr();
std::string msg = std::string(overloads->name) + "(): incompatible " +
std::string(overloads->is_constructor ? "constructor" : "function") +
" arguments. The following argument types are supported:\n";
int ctr = 0;
for (function_record *it2 = overloads; it2 != nullptr; it2 = it2->next) {
msg += " "+ std::to_string(++ctr) + ". ";
bool wrote_sig = false;
if (overloads->is_constructor) {
// For a constructor, rewrite `(self: Object, arg0, ...) -> NoneType` as `Object(arg0, ...)`
std::string sig = it2->signature;
size_t start = sig.find('(') + 7; // skip "(self: "
if (start < sig.size()) {
// End at the , for the next argument
size_t end = sig.find(", "), next = end + 2;
size_t ret = sig.rfind(" -> ");
// Or the ), if there is no comma:
if (end >= sig.size()) next = end = sig.find(')');
if (start < end && next < sig.size()) {
msg.append(sig, start, end - start);
msg += '(';
msg.append(sig, next, ret - next);
wrote_sig = true;
}
}
}
if (!wrote_sig) msg += it2->signature;
msg += "\n";
}
msg += "\nInvoked with: ";
auto args_ = reinterpret_borrow<tuple>(args_in);
bool some_args = false;
for (size_t ti = overloads->is_constructor ? 1 : 0; ti < args_.size(); ++ti) {
if (!some_args) some_args = true;
else msg += ", ";
msg += pybind11::repr(args_[ti]);
}
if (kwargs_in) {
auto kwargs = reinterpret_borrow<dict>(kwargs_in);
if (kwargs.size() > 0) {
if (some_args) msg += "; ";
msg += "kwargs: ";
bool first = true;
for (auto kwarg : kwargs) {
if (first) first = false;
else msg += ", ";
msg += pybind11::str("{}={!r}").format(kwarg.first, kwarg.second);
}
}
}
PyErr_SetString(PyExc_TypeError, msg.c_str());
return nullptr;
} else if (!result) {
std::string msg = "Unable to convert function return value to a "
"Python type! The signature was\n\t";
msg += it->signature;
PyErr_SetString(PyExc_TypeError, msg.c_str());
return nullptr;
} else {
if (overloads->is_constructor) {
auto tinfo = get_type_info((PyTypeObject *) overloads->scope.ptr());
auto *pi = reinterpret_cast<instance *>(parent.ptr());
auto v_h = pi->get_value_and_holder(tinfo);
if (!v_h.holder_constructed()) {
tinfo->init_instance(pi, nullptr);
}
}
return result.ptr();
}
}
};
/// Wrapper for Python extension modules
class module : public object {
public:
PYBIND11_OBJECT_DEFAULT(module, object, PyModule_Check)
/// Create a new top-level Python module with the given name and docstring
explicit module(const char *name, const char *doc = nullptr) {
if (!options::show_user_defined_docstrings()) doc = nullptr;
#if PY_MAJOR_VERSION >= 3
PyModuleDef *def = new PyModuleDef();
std::memset(def, 0, sizeof(PyModuleDef));
def->m_name = name;
def->m_doc = doc;
def->m_size = -1;
Py_INCREF(def);
m_ptr = PyModule_Create(def);
#else
m_ptr = Py_InitModule3(name, nullptr, doc);
#endif
if (m_ptr == nullptr)
pybind11_fail("Internal error in module::module()");
inc_ref();
}
/** \rst
Create Python binding for a new function within the module scope. ``Func``
can be a plain C++ function, a function pointer, or a lambda function. For
details on the ``Extra&& ... extra`` argument, see section :ref:`extras`.
\endrst */
template <typename Func, typename... Extra>
module &def(const char *name_, Func &&f, const Extra& ... extra) {
cpp_function func(std::forward<Func>(f), name(name_), scope(*this),
sibling(getattr(*this, name_, none())), extra...);
// NB: allow overwriting here because cpp_function sets up a chain with the intention of
// overwriting (and has already checked internally that it isn't overwriting non-functions).
add_object(name_, func, true /* overwrite */);
return *this;
}
/** \rst
Create and return a new Python submodule with the given name and docstring.
This also works recursively, i.e.
.. code-block:: cpp
py::module m("example", "pybind11 example plugin");
py::module m2 = m.def_submodule("sub", "A submodule of 'example'");
py::module m3 = m2.def_submodule("subsub", "A submodule of 'example.sub'");
\endrst */
module def_submodule(const char *name, const char *doc = nullptr) {
std::string full_name = std::string(PyModule_GetName(m_ptr))
+ std::string(".") + std::string(name);
auto result = reinterpret_borrow<module>(PyImport_AddModule(full_name.c_str()));
if (doc && options::show_user_defined_docstrings())
result.attr("__doc__") = pybind11::str(doc);
attr(name) = result;
return result;
}
/// Import and return a module or throws `error_already_set`.
static module import(const char *name) {
PyObject *obj = PyImport_ImportModule(name);
if (!obj)
throw error_already_set();
return reinterpret_steal<module>(obj);
}
// Adds an object to the module using the given name. Throws if an object with the given name
// already exists.
//
// overwrite should almost always be false: attempting to overwrite objects that pybind11 has
// established will, in most cases, break things.
PYBIND11_NOINLINE void add_object(const char *name, handle obj, bool overwrite = false) {
if (!overwrite && hasattr(*this, name))
pybind11_fail("Error during initialization: multiple incompatible definitions with name \"" +
std::string(name) + "\"");
PyModule_AddObject(ptr(), name, obj.inc_ref().ptr() /* steals a reference */);
}
};
/// \ingroup python_builtins
/// Return a dictionary representing the global variables in the current execution frame,
/// or ``__main__.__dict__`` if there is no frame (usually when the interpreter is embedded).
inline dict globals() {
PyObject *p = PyEval_GetGlobals();
return reinterpret_borrow<dict>(p ? p : module::import("__main__").attr("__dict__").ptr());
}
NAMESPACE_BEGIN(detail)
/// Generic support for creating new Python heap types
class generic_type : public object {
template <typename...> friend class class_;
public:
PYBIND11_OBJECT_DEFAULT(generic_type, object, PyType_Check)
protected:
void initialize(const type_record &rec) {
if (rec.scope && hasattr(rec.scope, rec.name))
pybind11_fail("generic_type: cannot initialize type \"" + std::string(rec.name) +
"\": an object with that name is already defined");
if (rec.module_local ? get_local_type_info(*rec.type) : get_global_type_info(*rec.type))
pybind11_fail("generic_type: type \"" + std::string(rec.name) +
"\" is already registered!");
m_ptr = make_new_python_type(rec);
/* Register supplemental type information in C++ dict */
auto *tinfo = new detail::type_info();
tinfo->type = (PyTypeObject *) m_ptr;
tinfo->cpptype = rec.type;
tinfo->type_size = rec.type_size;
tinfo->operator_new = rec.operator_new;
tinfo->holder_size_in_ptrs = size_in_ptrs(rec.holder_size);
tinfo->init_instance = rec.init_instance;
tinfo->dealloc = rec.dealloc;
tinfo->simple_type = true;
tinfo->simple_ancestors = true;
tinfo->default_holder = rec.default_holder;
tinfo->module_local = rec.module_local;
auto &internals = get_internals();
auto tindex = std::type_index(*rec.type);
tinfo->direct_conversions = &internals.direct_conversions[tindex];
if (rec.module_local)
registered_local_types_cpp()[tindex] = tinfo;
else
internals.registered_types_cpp[tindex] = tinfo;
internals.registered_types_py[(PyTypeObject *) m_ptr] = { tinfo };
if (rec.bases.size() > 1 || rec.multiple_inheritance) {
mark_parents_nonsimple(tinfo->type);
tinfo->simple_ancestors = false;
}
else if (rec.bases.size() == 1) {
auto parent_tinfo = get_type_info((PyTypeObject *) rec.bases[0].ptr());
tinfo->simple_ancestors = parent_tinfo->simple_ancestors;
}
if (rec.module_local) {
// Stash the local typeinfo and loader so that external modules can access it.
tinfo->module_local_load = &type_caster_generic::local_load;
setattr(m_ptr, PYBIND11_MODULE_LOCAL_ID, capsule(tinfo));
}
}
/// Helper function which tags all parents of a type using mult. inheritance
void mark_parents_nonsimple(PyTypeObject *value) {
auto t = reinterpret_borrow<tuple>(value->tp_bases);
for (handle h : t) {
auto tinfo2 = get_type_info((PyTypeObject *) h.ptr());
if (tinfo2)
tinfo2->simple_type = false;
mark_parents_nonsimple((PyTypeObject *) h.ptr());
}
}
void install_buffer_funcs(
buffer_info *(*get_buffer)(PyObject *, void *),
void *get_buffer_data) {
PyHeapTypeObject *type = (PyHeapTypeObject*) m_ptr;
auto tinfo = detail::get_type_info(&type->ht_type);
if (!type->ht_type.tp_as_buffer)
pybind11_fail(
"To be able to register buffer protocol support for the type '" +
std::string(tinfo->type->tp_name) +
"' the associated class<>(..) invocation must "
"include the pybind11::buffer_protocol() annotation!");
tinfo->get_buffer = get_buffer;
tinfo->get_buffer_data = get_buffer_data;
}
void def_property_static_impl(const char *name,
handle fget, handle fset,
detail::function_record *rec_fget) {
const auto is_static = !(rec_fget->is_method && rec_fget->scope);
const auto has_doc = rec_fget->doc && pybind11::options::show_user_defined_docstrings();
auto property = handle((PyObject *) (is_static ? get_internals().static_property_type
: &PyProperty_Type));
attr(name) = property(fget.ptr() ? fget : none(),
fset.ptr() ? fset : none(),
/*deleter*/none(),
pybind11::str(has_doc ? rec_fget->doc : ""));
}
};
/// Set the pointer to operator new if it exists. The cast is needed because it can be overloaded.
template <typename T, typename = void_t<decltype(static_cast<void *(*)(size_t)>(T::operator new))>>
void set_operator_new(type_record *r) { r->operator_new = &T::operator new; }
template <typename> void set_operator_new(...) { }
template <typename T, typename SFINAE = void> struct has_operator_delete : std::false_type { };
template <typename T> struct has_operator_delete<T, void_t<decltype(static_cast<void (*)(void *)>(T::operator delete))>>
: std::true_type { };
template <typename T, typename SFINAE = void> struct has_operator_delete_size : std::false_type { };
template <typename T> struct has_operator_delete_size<T, void_t<decltype(static_cast<void (*)(void *, size_t)>(T::operator delete))>>
: std::true_type { };
/// Call class-specific delete if it exists or global otherwise. Can also be an overload set.
template <typename T, enable_if_t<has_operator_delete<T>::value, int> = 0>
void call_operator_delete(T *p, size_t) { T::operator delete(p); }
template <typename T, enable_if_t<!has_operator_delete<T>::value && has_operator_delete_size<T>::value, int> = 0>
void call_operator_delete(T *p, size_t s) { T::operator delete(p, s); }
inline void call_operator_delete(void *p, size_t) { ::operator delete(p); }
NAMESPACE_END(detail)
/// Given a pointer to a member function, cast it to its `Derived` version.
/// Forward everything else unchanged.
template <typename /*Derived*/, typename F>
auto method_adaptor(F &&f) -> decltype(std::forward<F>(f)) { return std::forward<F>(f); }
template <typename Derived, typename Return, typename Class, typename... Args>
auto method_adaptor(Return (Class::*pmf)(Args...)) -> Return (Derived::*)(Args...) { return pmf; }
template <typename Derived, typename Return, typename Class, typename... Args>
auto method_adaptor(Return (Class::*pmf)(Args...) const) -> Return (Derived::*)(Args...) const { return pmf; }
template <typename type_, typename... options>
class class_ : public detail::generic_type {
template <typename T> using is_holder = detail::is_holder_type<type_, T>;
template <typename T> using is_subtype = detail::is_strict_base_of<type_, T>;
template <typename T> using is_base = detail::is_strict_base_of<T, type_>;
// struct instead of using here to help MSVC:
template <typename T> struct is_valid_class_option :
detail::any_of<is_holder<T>, is_subtype<T>, is_base<T>> {};
public:
using type = type_;
using type_alias = detail::exactly_one_t<is_subtype, void, options...>;
constexpr static bool has_alias = !std::is_void<type_alias>::value;
using holder_type = detail::exactly_one_t<is_holder, std::unique_ptr<type>, options...>;
static_assert(detail::all_of<is_valid_class_option<options>...>::value,
"Unknown/invalid class_ template parameters provided");
static_assert(!has_alias || std::is_polymorphic<type>::value,
"Cannot use an alias class with a non-polymorphic type");
PYBIND11_OBJECT(class_, generic_type, PyType_Check)
template <typename... Extra>
class_(handle scope, const char *name, const Extra &... extra) {
using namespace detail;
// MI can only be specified via class_ template options, not constructor parameters
static_assert(
none_of<is_pyobject<Extra>...>::value || // no base class arguments, or:
( constexpr_sum(is_pyobject<Extra>::value...) == 1 && // Exactly one base
constexpr_sum(is_base<options>::value...) == 0 && // no template option bases
none_of<std::is_same<multiple_inheritance, Extra>...>::value), // no multiple_inheritance attr
"Error: multiple inheritance bases must be specified via class_ template options");
type_record record;
record.scope = scope;
record.name = name;
record.type = &typeid(type);
record.type_size = sizeof(conditional_t<has_alias, type_alias, type>);
record.holder_size = sizeof(holder_type);
record.init_instance = init_instance;
record.dealloc = dealloc;
record.default_holder = std::is_same<holder_type, std::unique_ptr<type>>::value;
set_operator_new<type>(&record);
/* Register base classes specified via template arguments to class_, if any */