| /* |
| pybind11/detail/descr.h: Helper type for concatenating type signatures |
| either at runtime (C++11) or compile time (C++14) |
| |
| 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 |
| |
| #include "common.h" |
| |
| NAMESPACE_BEGIN(PYBIND11_NAMESPACE) |
| NAMESPACE_BEGIN(detail) |
| |
| /* Concatenate type signatures at compile time using C++14 */ |
| #if defined(PYBIND11_CPP14) && !defined(_MSC_VER) |
| #define PYBIND11_CONSTEXPR_DESCR |
| |
| template <size_t Size1, size_t Size2> class descr { |
| template <size_t Size1_, size_t Size2_> friend class descr; |
| public: |
| constexpr descr(char const (&text) [Size1+1], const std::type_info * const (&types)[Size2+1]) |
| : descr(text, types, |
| make_index_sequence<Size1>(), |
| make_index_sequence<Size2>()) { } |
| |
| constexpr const char *text() const { return m_text; } |
| constexpr const std::type_info * const * types() const { return m_types; } |
| |
| template <size_t OtherSize1, size_t OtherSize2> |
| constexpr descr<Size1 + OtherSize1, Size2 + OtherSize2> operator+(const descr<OtherSize1, OtherSize2> &other) const { |
| return concat(other, |
| make_index_sequence<Size1>(), |
| make_index_sequence<Size2>(), |
| make_index_sequence<OtherSize1>(), |
| make_index_sequence<OtherSize2>()); |
| } |
| |
| protected: |
| template <size_t... Indices1, size_t... Indices2> |
| constexpr descr( |
| char const (&text) [Size1+1], |
| const std::type_info * const (&types) [Size2+1], |
| index_sequence<Indices1...>, index_sequence<Indices2...>) |
| : m_text{text[Indices1]..., '\0'}, |
| m_types{types[Indices2]..., nullptr } {} |
| |
| template <size_t OtherSize1, size_t OtherSize2, size_t... Indices1, |
| size_t... Indices2, size_t... OtherIndices1, size_t... OtherIndices2> |
| constexpr descr<Size1 + OtherSize1, Size2 + OtherSize2> |
| concat(const descr<OtherSize1, OtherSize2> &other, |
| index_sequence<Indices1...>, index_sequence<Indices2...>, |
| index_sequence<OtherIndices1...>, index_sequence<OtherIndices2...>) const { |
| return descr<Size1 + OtherSize1, Size2 + OtherSize2>( |
| { m_text[Indices1]..., other.m_text[OtherIndices1]..., '\0' }, |
| { m_types[Indices2]..., other.m_types[OtherIndices2]..., nullptr } |
| ); |
| } |
| |
| protected: |
| char m_text[Size1 + 1]; |
| const std::type_info * m_types[Size2 + 1]; |
| }; |
| |
| template <size_t Size> constexpr descr<Size - 1, 0> _(char const(&text)[Size]) { |
| return descr<Size - 1, 0>(text, { nullptr }); |
| } |
| |
| template <size_t Rem, size_t... Digits> struct int_to_str : int_to_str<Rem/10, Rem%10, Digits...> { }; |
| template <size_t...Digits> struct int_to_str<0, Digits...> { |
| static constexpr auto digits = descr<sizeof...(Digits), 0>({ ('0' + Digits)..., '\0' }, { nullptr }); |
| }; |
| |
| // Ternary description (like std::conditional) |
| template <bool B, size_t Size1, size_t Size2> |
| constexpr enable_if_t<B, descr<Size1 - 1, 0>> _(char const(&text1)[Size1], char const(&)[Size2]) { |
| return _(text1); |
| } |
| template <bool B, size_t Size1, size_t Size2> |
| constexpr enable_if_t<!B, descr<Size2 - 1, 0>> _(char const(&)[Size1], char const(&text2)[Size2]) { |
| return _(text2); |
| } |
| template <bool B, size_t SizeA1, size_t SizeA2, size_t SizeB1, size_t SizeB2> |
| constexpr enable_if_t<B, descr<SizeA1, SizeA2>> _(descr<SizeA1, SizeA2> d, descr<SizeB1, SizeB2>) { return d; } |
| template <bool B, size_t SizeA1, size_t SizeA2, size_t SizeB1, size_t SizeB2> |
| constexpr enable_if_t<!B, descr<SizeB1, SizeB2>> _(descr<SizeA1, SizeA2>, descr<SizeB1, SizeB2> d) { return d; } |
| |
| template <size_t Size> auto constexpr _() -> decltype(int_to_str<Size / 10, Size % 10>::digits) { |
| return int_to_str<Size / 10, Size % 10>::digits; |
| } |
| |
| template <typename Type> constexpr descr<1, 1> _() { |
| return descr<1, 1>({ '%', '\0' }, { &typeid(Type), nullptr }); |
| } |
| |
| inline constexpr descr<0, 0> concat() { return _(""); } |
| template <size_t Size1, size_t Size2, typename... Args> auto constexpr concat(descr<Size1, Size2> descr) { return descr; } |
| template <size_t Size1, size_t Size2, typename... Args> auto constexpr concat(descr<Size1, Size2> descr, Args&&... args) { return descr + _(", ") + concat(args...); } |
| template <size_t Size1, size_t Size2> auto constexpr type_descr(descr<Size1, Size2> descr) { return _("{") + descr + _("}"); } |
| |
| #define PYBIND11_DESCR constexpr auto |
| |
| #else /* Simpler C++11 implementation based on run-time memory allocation and copying */ |
| |
| class descr { |
| public: |
| PYBIND11_NOINLINE descr(const char *text, const std::type_info * const * types) { |
| size_t nChars = len(text), nTypes = len(types); |
| m_text = new char[nChars]; |
| m_types = new const std::type_info *[nTypes]; |
| memcpy(m_text, text, nChars * sizeof(char)); |
| memcpy(m_types, types, nTypes * sizeof(const std::type_info *)); |
| } |
| |
| PYBIND11_NOINLINE descr operator+(descr &&d2) && { |
| descr r; |
| |
| size_t nChars1 = len(m_text), nTypes1 = len(m_types); |
| size_t nChars2 = len(d2.m_text), nTypes2 = len(d2.m_types); |
| |
| r.m_text = new char[nChars1 + nChars2 - 1]; |
| r.m_types = new const std::type_info *[nTypes1 + nTypes2 - 1]; |
| memcpy(r.m_text, m_text, (nChars1-1) * sizeof(char)); |
| memcpy(r.m_text + nChars1 - 1, d2.m_text, nChars2 * sizeof(char)); |
| memcpy(r.m_types, m_types, (nTypes1-1) * sizeof(std::type_info *)); |
| memcpy(r.m_types + nTypes1 - 1, d2.m_types, nTypes2 * sizeof(std::type_info *)); |
| |
| delete[] m_text; delete[] m_types; |
| delete[] d2.m_text; delete[] d2.m_types; |
| |
| return r; |
| } |
| |
| char *text() { return m_text; } |
| const std::type_info * * types() { return m_types; } |
| |
| protected: |
| PYBIND11_NOINLINE descr() { } |
| |
| template <typename T> static size_t len(const T *ptr) { // return length including null termination |
| const T *it = ptr; |
| while (*it++ != (T) 0) |
| ; |
| return static_cast<size_t>(it - ptr); |
| } |
| |
| const std::type_info **m_types = nullptr; |
| char *m_text = nullptr; |
| }; |
| |
| /* The 'PYBIND11_NOINLINE inline' combinations below are intentional to get the desired linkage while producing as little object code as possible */ |
| |
| PYBIND11_NOINLINE inline descr _(const char *text) { |
| const std::type_info *types[1] = { nullptr }; |
| return descr(text, types); |
| } |
| |
| template <bool B> PYBIND11_NOINLINE enable_if_t<B, descr> _(const char *text1, const char *) { return _(text1); } |
| template <bool B> PYBIND11_NOINLINE enable_if_t<!B, descr> _(char const *, const char *text2) { return _(text2); } |
| template <bool B> PYBIND11_NOINLINE enable_if_t<B, descr> _(descr d, descr) { return d; } |
| template <bool B> PYBIND11_NOINLINE enable_if_t<!B, descr> _(descr, descr d) { return d; } |
| |
| template <typename Type> PYBIND11_NOINLINE descr _() { |
| const std::type_info *types[2] = { &typeid(Type), nullptr }; |
| return descr("%", types); |
| } |
| |
| template <size_t Size> PYBIND11_NOINLINE descr _() { |
| const std::type_info *types[1] = { nullptr }; |
| return descr(std::to_string(Size).c_str(), types); |
| } |
| |
| PYBIND11_NOINLINE inline descr concat() { return _(""); } |
| PYBIND11_NOINLINE inline descr concat(descr &&d) { return d; } |
| template <typename... Args> PYBIND11_NOINLINE descr concat(descr &&d, Args&&... args) { return std::move(d) + _(", ") + concat(std::forward<Args>(args)...); } |
| PYBIND11_NOINLINE inline descr type_descr(descr&& d) { return _("{") + std::move(d) + _("}"); } |
| |
| #define PYBIND11_DESCR ::pybind11::detail::descr |
| #endif |
| |
| NAMESPACE_END(detail) |
| NAMESPACE_END(PYBIND11_NAMESPACE) |