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Diffstat (limited to 'ext/pybind11/include/pybind11/stl_bind.h')
-rw-r--r-- | ext/pybind11/include/pybind11/stl_bind.h | 541 |
1 files changed, 541 insertions, 0 deletions
diff --git a/ext/pybind11/include/pybind11/stl_bind.h b/ext/pybind11/include/pybind11/stl_bind.h new file mode 100644 index 000000000..ef9950ebb --- /dev/null +++ b/ext/pybind11/include/pybind11/stl_bind.h @@ -0,0 +1,541 @@ +/* + pybind11/std_bind.h: Binding generators for STL data types + + Copyright (c) 2016 Sergey Lyskov and Wenzel Jakob + + 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 + +#include "common.h" +#include "operators.h" + +#include <algorithm> +#include <sstream> + +NAMESPACE_BEGIN(pybind11) +NAMESPACE_BEGIN(detail) + +/* SFINAE helper class used by 'is_comparable */ +template <typename T> struct container_traits { + template <typename T2> static std::true_type test_comparable(decltype(std::declval<const T2 &>() == std::declval<const T2 &>())*); + template <typename T2> static std::false_type test_comparable(...); + template <typename T2> static std::true_type test_value(typename T2::value_type *); + template <typename T2> static std::false_type test_value(...); + template <typename T2> static std::true_type test_pair(typename T2::first_type *, typename T2::second_type *); + template <typename T2> static std::false_type test_pair(...); + + static constexpr const bool is_comparable = std::is_same<std::true_type, decltype(test_comparable<T>(nullptr))>::value; + static constexpr const bool is_pair = std::is_same<std::true_type, decltype(test_pair<T>(nullptr, nullptr))>::value; + static constexpr const bool is_vector = std::is_same<std::true_type, decltype(test_value<T>(nullptr))>::value; + static constexpr const bool is_element = !is_pair && !is_vector; +}; + +/* Default: is_comparable -> std::false_type */ +template <typename T, typename SFINAE = void> +struct is_comparable : std::false_type { }; + +/* For non-map data structures, check whether operator== can be instantiated */ +template <typename T> +struct is_comparable< + T, enable_if_t<container_traits<T>::is_element && + container_traits<T>::is_comparable>> + : std::true_type { }; + +/* For a vector/map data structure, recursively check the value type (which is std::pair for maps) */ +template <typename T> +struct is_comparable<T, enable_if_t<container_traits<T>::is_vector>> { + static constexpr const bool value = + is_comparable<typename T::value_type>::value; +}; + +/* For pairs, recursively check the two data types */ +template <typename T> +struct is_comparable<T, enable_if_t<container_traits<T>::is_pair>> { + static constexpr const bool value = + is_comparable<typename T::first_type>::value && + is_comparable<typename T::second_type>::value; +}; + +/* Fallback functions */ +template <typename, typename, typename... Args> void vector_if_copy_constructible(const Args &...) { } +template <typename, typename, typename... Args> void vector_if_equal_operator(const Args &...) { } +template <typename, typename, typename... Args> void vector_if_insertion_operator(const Args &...) { } +template <typename, typename, typename... Args> void vector_modifiers(const Args &...) { } + +template<typename Vector, typename Class_> +void vector_if_copy_constructible(enable_if_t< + std::is_copy_constructible<Vector>::value && + std::is_copy_constructible<typename Vector::value_type>::value, Class_> &cl) { + + cl.def(pybind11::init<const Vector &>(), "Copy constructor"); +} + +template<typename Vector, typename Class_> +void vector_if_equal_operator(enable_if_t<is_comparable<Vector>::value, Class_> &cl) { + using T = typename Vector::value_type; + + cl.def(self == self); + cl.def(self != self); + + cl.def("count", + [](const Vector &v, const T &x) { + return std::count(v.begin(), v.end(), x); + }, + arg("x"), + "Return the number of times ``x`` appears in the list" + ); + + cl.def("remove", [](Vector &v, const T &x) { + auto p = std::find(v.begin(), v.end(), x); + if (p != v.end()) + v.erase(p); + else + throw pybind11::value_error(); + }, + arg("x"), + "Remove the first item from the list whose value is x. " + "It is an error if there is no such item." + ); + + cl.def("__contains__", + [](const Vector &v, const T &x) { + return std::find(v.begin(), v.end(), x) != v.end(); + }, + arg("x"), + "Return true the container contains ``x``" + ); +} + +// Vector modifiers -- requires a copyable vector_type: +// (Technically, some of these (pop and __delitem__) don't actually require copyability, but it seems +// silly to allow deletion but not insertion, so include them here too.) +template <typename Vector, typename Class_> +void vector_modifiers(enable_if_t<std::is_copy_constructible<typename Vector::value_type>::value, Class_> &cl) { + using T = typename Vector::value_type; + using SizeType = typename Vector::size_type; + using DiffType = typename Vector::difference_type; + + cl.def("append", + [](Vector &v, const T &value) { v.push_back(value); }, + arg("x"), + "Add an item to the end of the list"); + + cl.def("__init__", [](Vector &v, iterable it) { + new (&v) Vector(); + try { + v.reserve(len(it)); + for (handle h : it) + v.push_back(h.cast<T>()); + } catch (...) { + v.~Vector(); + throw; + } + }); + + cl.def("extend", + [](Vector &v, const Vector &src) { + v.reserve(v.size() + src.size()); + v.insert(v.end(), src.begin(), src.end()); + }, + arg("L"), + "Extend the list by appending all the items in the given list" + ); + + cl.def("insert", + [](Vector &v, SizeType i, const T &x) { + v.insert(v.begin() + (DiffType) i, x); + }, + arg("i") , arg("x"), + "Insert an item at a given position." + ); + + cl.def("pop", + [](Vector &v) { + if (v.empty()) + throw pybind11::index_error(); + T t = v.back(); + v.pop_back(); + return t; + }, + "Remove and return the last item" + ); + + cl.def("pop", + [](Vector &v, SizeType i) { + if (i >= v.size()) + throw pybind11::index_error(); + T t = v[i]; + v.erase(v.begin() + (DiffType) i); + return t; + }, + arg("i"), + "Remove and return the item at index ``i``" + ); + + cl.def("__setitem__", + [](Vector &v, SizeType i, const T &t) { + if (i >= v.size()) + throw pybind11::index_error(); + v[i] = t; + } + ); + + /// Slicing protocol + cl.def("__getitem__", + [](const Vector &v, slice slice) -> Vector * { + size_t start, stop, step, slicelength; + + if (!slice.compute(v.size(), &start, &stop, &step, &slicelength)) + throw pybind11::error_already_set(); + + Vector *seq = new Vector(); + seq->reserve((size_t) slicelength); + + for (size_t i=0; i<slicelength; ++i) { + seq->push_back(v[start]); + start += step; + } + return seq; + }, + arg("s"), + "Retrieve list elements using a slice object" + ); + + cl.def("__setitem__", + [](Vector &v, slice slice, const Vector &value) { + size_t start, stop, step, slicelength; + if (!slice.compute(v.size(), &start, &stop, &step, &slicelength)) + throw pybind11::error_already_set(); + + if (slicelength != value.size()) + throw std::runtime_error("Left and right hand size of slice assignment have different sizes!"); + + for (size_t i=0; i<slicelength; ++i) { + v[start] = value[i]; + start += step; + } + }, + "Assign list elements using a slice object" + ); + + cl.def("__delitem__", + [](Vector &v, SizeType i) { + if (i >= v.size()) + throw pybind11::index_error(); + v.erase(v.begin() + DiffType(i)); + }, + "Delete the list elements at index ``i``" + ); + + cl.def("__delitem__", + [](Vector &v, slice slice) { + size_t start, stop, step, slicelength; + + if (!slice.compute(v.size(), &start, &stop, &step, &slicelength)) + throw pybind11::error_already_set(); + + if (step == 1 && false) { + v.erase(v.begin() + (DiffType) start, v.begin() + DiffType(start + slicelength)); + } else { + for (size_t i = 0; i < slicelength; ++i) { + v.erase(v.begin() + DiffType(start)); + start += step - 1; + } + } + }, + "Delete list elements using a slice object" + ); + +} + +// If the type has an operator[] that doesn't return a reference (most notably std::vector<bool>), +// we have to access by copying; otherwise we return by reference. +template <typename Vector> using vector_needs_copy = bool_constant< + !std::is_same<decltype(std::declval<Vector>()[typename Vector::size_type()]), typename Vector::value_type &>::value>; + +// The usual case: access and iterate by reference +template <typename Vector, typename Class_> +void vector_accessor(enable_if_t<!vector_needs_copy<Vector>::value, Class_> &cl) { + using T = typename Vector::value_type; + using SizeType = typename Vector::size_type; + using ItType = typename Vector::iterator; + + cl.def("__getitem__", + [](Vector &v, SizeType i) -> T & { + if (i >= v.size()) + throw pybind11::index_error(); + return v[i]; + }, + return_value_policy::reference_internal // ref + keepalive + ); + + cl.def("__iter__", + [](Vector &v) { + return pybind11::make_iterator< + return_value_policy::reference_internal, ItType, ItType, T&>( + v.begin(), v.end()); + }, + keep_alive<0, 1>() /* Essential: keep list alive while iterator exists */ + ); +} + +// The case for special objects, like std::vector<bool>, that have to be returned-by-copy: +template <typename Vector, typename Class_> +void vector_accessor(enable_if_t<vector_needs_copy<Vector>::value, Class_> &cl) { + using T = typename Vector::value_type; + using SizeType = typename Vector::size_type; + using ItType = typename Vector::iterator; + cl.def("__getitem__", + [](const Vector &v, SizeType i) -> T { + if (i >= v.size()) + throw pybind11::index_error(); + return v[i]; + } + ); + + cl.def("__iter__", + [](Vector &v) { + return pybind11::make_iterator< + return_value_policy::copy, ItType, ItType, T>( + v.begin(), v.end()); + }, + keep_alive<0, 1>() /* Essential: keep list alive while iterator exists */ + ); +} + +template <typename Vector, typename Class_> auto vector_if_insertion_operator(Class_ &cl, std::string const &name) + -> decltype(std::declval<std::ostream&>() << std::declval<typename Vector::value_type>(), void()) { + using size_type = typename Vector::size_type; + + cl.def("__repr__", + [name](Vector &v) { + std::ostringstream s; + s << name << '['; + for (size_type i=0; i < v.size(); ++i) { + s << v[i]; + if (i != v.size() - 1) + s << ", "; + } + s << ']'; + return s.str(); + }, + "Return the canonical string representation of this list." + ); +} + +NAMESPACE_END(detail) + +// +// std::vector +// +template <typename Vector, typename holder_type = std::unique_ptr<Vector>, typename... Args> +pybind11::class_<Vector, holder_type> bind_vector(pybind11::module &m, std::string const &name, Args&&... args) { + using Class_ = pybind11::class_<Vector, holder_type>; + + Class_ cl(m, name.c_str(), std::forward<Args>(args)...); + + cl.def(pybind11::init<>()); + + // Register copy constructor (if possible) + detail::vector_if_copy_constructible<Vector, Class_>(cl); + + // Register comparison-related operators and functions (if possible) + detail::vector_if_equal_operator<Vector, Class_>(cl); + + // Register stream insertion operator (if possible) + detail::vector_if_insertion_operator<Vector, Class_>(cl, name); + + // Modifiers require copyable vector value type + detail::vector_modifiers<Vector, Class_>(cl); + + // Accessor and iterator; return by value if copyable, otherwise we return by ref + keep-alive + detail::vector_accessor<Vector, Class_>(cl); + + cl.def("__bool__", + [](const Vector &v) -> bool { + return !v.empty(); + }, + "Check whether the list is nonempty" + ); + + cl.def("__len__", &Vector::size); + + + + +#if 0 + // C++ style functions deprecated, leaving it here as an example + cl.def(pybind11::init<size_type>()); + + cl.def("resize", + (void (Vector::*) (size_type count)) & Vector::resize, + "changes the number of elements stored"); + + cl.def("erase", + [](Vector &v, SizeType i) { + if (i >= v.size()) + throw pybind11::index_error(); + v.erase(v.begin() + i); + }, "erases element at index ``i``"); + + cl.def("empty", &Vector::empty, "checks whether the container is empty"); + cl.def("size", &Vector::size, "returns the number of elements"); + cl.def("push_back", (void (Vector::*)(const T&)) &Vector::push_back, "adds an element to the end"); + cl.def("pop_back", &Vector::pop_back, "removes the last element"); + + cl.def("max_size", &Vector::max_size, "returns the maximum possible number of elements"); + cl.def("reserve", &Vector::reserve, "reserves storage"); + cl.def("capacity", &Vector::capacity, "returns the number of elements that can be held in currently allocated storage"); + cl.def("shrink_to_fit", &Vector::shrink_to_fit, "reduces memory usage by freeing unused memory"); + + cl.def("clear", &Vector::clear, "clears the contents"); + cl.def("swap", &Vector::swap, "swaps the contents"); + + cl.def("front", [](Vector &v) { + if (v.size()) return v.front(); + else throw pybind11::index_error(); + }, "access the first element"); + + cl.def("back", [](Vector &v) { + if (v.size()) return v.back(); + else throw pybind11::index_error(); + }, "access the last element "); + +#endif + + return cl; +} + + + +// +// std::map, std::unordered_map +// + +NAMESPACE_BEGIN(detail) + +/* Fallback functions */ +template <typename, typename, typename... Args> void map_if_insertion_operator(const Args &...) { } +template <typename, typename, typename... Args> void map_assignment(const Args &...) { } + +// Map assignment when copy-assignable: just copy the value +template <typename Map, typename Class_> +void map_assignment(enable_if_t<std::is_copy_assignable<typename Map::mapped_type>::value, Class_> &cl) { + using KeyType = typename Map::key_type; + using MappedType = typename Map::mapped_type; + + cl.def("__setitem__", + [](Map &m, const KeyType &k, const MappedType &v) { + auto it = m.find(k); + if (it != m.end()) it->second = v; + else m.emplace(k, v); + } + ); +} + +// Not copy-assignable, but still copy-constructible: we can update the value by erasing and reinserting +template<typename Map, typename Class_> +void map_assignment(enable_if_t< + !std::is_copy_assignable<typename Map::mapped_type>::value && + std::is_copy_constructible<typename Map::mapped_type>::value, + Class_> &cl) { + using KeyType = typename Map::key_type; + using MappedType = typename Map::mapped_type; + + cl.def("__setitem__", + [](Map &m, const KeyType &k, const MappedType &v) { + // We can't use m[k] = v; because value type might not be default constructable + auto r = m.emplace(k, v); + if (!r.second) { + // value type is not copy assignable so the only way to insert it is to erase it first... + m.erase(r.first); + m.emplace(k, v); + } + } + ); +} + + +template <typename Map, typename Class_> auto map_if_insertion_operator(Class_ &cl, std::string const &name) +-> decltype(std::declval<std::ostream&>() << std::declval<typename Map::key_type>() << std::declval<typename Map::mapped_type>(), void()) { + + cl.def("__repr__", + [name](Map &m) { + std::ostringstream s; + s << name << '{'; + bool f = false; + for (auto const &kv : m) { + if (f) + s << ", "; + s << kv.first << ": " << kv.second; + f = true; + } + s << '}'; + return s.str(); + }, + "Return the canonical string representation of this map." + ); +} + + +NAMESPACE_END(detail) + +template <typename Map, typename holder_type = std::unique_ptr<Map>, typename... Args> +pybind11::class_<Map, holder_type> bind_map(module &m, const std::string &name, Args&&... args) { + using KeyType = typename Map::key_type; + using MappedType = typename Map::mapped_type; + using Class_ = pybind11::class_<Map, holder_type>; + + Class_ cl(m, name.c_str(), std::forward<Args>(args)...); + + cl.def(pybind11::init<>()); + + // Register stream insertion operator (if possible) + detail::map_if_insertion_operator<Map, Class_>(cl, name); + + cl.def("__bool__", + [](const Map &m) -> bool { return !m.empty(); }, + "Check whether the map is nonempty" + ); + + cl.def("__iter__", + [](Map &m) { return pybind11::make_key_iterator(m.begin(), m.end()); }, + pybind11::keep_alive<0, 1>() /* Essential: keep list alive while iterator exists */ + ); + + cl.def("items", + [](Map &m) { return pybind11::make_iterator(m.begin(), m.end()); }, + pybind11::keep_alive<0, 1>() /* Essential: keep list alive while iterator exists */ + ); + + cl.def("__getitem__", + [](Map &m, const KeyType &k) -> MappedType & { + auto it = m.find(k); + if (it == m.end()) + throw pybind11::key_error(); + return it->second; + }, + return_value_policy::reference_internal // ref + keepalive + ); + + // Assignment provided only if the type is copyable + detail::map_assignment<Map, Class_>(cl); + + cl.def("__delitem__", + [](Map &m, const KeyType &k) { + auto it = m.find(k); + if (it == m.end()) + throw pybind11::key_error(); + return m.erase(it); + } + ); + + cl.def("__len__", &Map::size); + + return cl; +} + +NAMESPACE_END(pybind11) |