[libcxx-commits] [libcxx] [libc++][c++23] P2374: `views::cartesian_product` (PR #111215)
via libcxx-commits
libcxx-commits at lists.llvm.org
Sun Nov 3 12:46:37 PST 2024
https://github.com/PaulXiCao updated https://github.com/llvm/llvm-project/pull/111215
>From b924fd473793394d8b8bd16e83f3acc5211937f4 Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Fri, 4 Oct 2024 19:04:39 +0200
Subject: [PATCH 01/37] wip
---
libcxx/include/CMakeLists.txt | 1 +
.../include/__ranges/cartesian_product_view.h | 95 +++++++++++++++++++
libcxx/include/ranges | 1 +
.../ctor.pass.cpp | 36 +++++++
.../size.pass.cpp | 46 +++++++++
5 files changed, 179 insertions(+)
create mode 100644 libcxx/include/__ranges/cartesian_product_view.h
create mode 100644 libcxx/test/std/ranges/range.adaptors/range.cartesian.product.view/ctor.pass.cpp
create mode 100644 libcxx/test/std/ranges/range.adaptors/range.cartesian.product.view/size.pass.cpp
diff --git a/libcxx/include/CMakeLists.txt b/libcxx/include/CMakeLists.txt
index 8a63280053340f..ae8dbcafd9ae61 100644
--- a/libcxx/include/CMakeLists.txt
+++ b/libcxx/include/CMakeLists.txt
@@ -647,6 +647,7 @@ set(files
__ranges/access.h
__ranges/all.h
__ranges/as_rvalue_view.h
+ __ranges/cartesian_product_view.h
__ranges/chunk_by_view.h
__ranges/common_view.h
__ranges/concepts.h
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
new file mode 100644
index 00000000000000..46941b9e1c97dd
--- /dev/null
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -0,0 +1,95 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANGES_CARTESIAN_PRODUCT_VIEW_H
+#define _LIBCPP___RANGES_CARTESIAN_PRODUCT_VIEW_H
+
+#include <__config>
+#include <__ranges/concepts.h> // forward_range, view, range_size_t, sized_range, ...
+#include <tuple> // apply
+#include <type_traits> // common_type_t
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 23
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace ranges {
+
+template <input_range First, forward_range... Vs>
+ requires(view<First> && ... && view<Vs>)
+class cartesian_product_view : public view_interface<cartesian_product_view<First, Vs...>> {
+private:
+ tuple<First, Vs...> bases_; // exposition only
+
+ template <bool Const>
+ struct iterator; // exposition only
+
+public:
+ constexpr cartesian_product_view() = default;
+ constexpr explicit cartesian_product_view(First first_base, Vs... bases)
+ : bases_{std::move(first_base), std::move(bases)...} {}
+
+ // constexpr iterator<false> begin()
+ // requires (!simple-view<First> || ... || !simple-view<Vs>)
+ // {
+ // return move_iterator(ranges::begin(bases_));
+ // }
+
+ // constexpr iterator<true> begin() const
+ // requires (range<const First> && ... && range<const Vs>)
+ // {
+ // return move_iterator(ranges::begin(__base_));
+ // }
+
+ // constexpr iterator<false> begin()
+ // requires (!simple-view<First> || ... || !simple-view<Vs>);
+ // constexpr iterator<true> begin() const
+ // requires (range<const First> && ... && range<const Vs>);
+
+ // constexpr iterator<false> end()
+ // requires ((!simple-view<First> || ... || !simple-view<Vs>) &&
+ // cartesian-product-is-common<First, Vs...>);
+ // constexpr iterator<true> end() const
+ // requires cartesian-product-is-common<const First, const Vs...>;
+ // constexpr default_sentinel_t end() const noexcept;
+
+ // constexpr see below size()
+ // requires cartesian-product-is-sized<First, Vs...>;
+ // constexpr see below size() const
+ // requires cartesian-product-is-sized<const First, const Vs...>;
+ constexpr auto size() const
+ requires(sized_range<const First> && ... && sized_range<const Vs>)
+ {
+ return std::apply(
+ [](auto&&... bases) {
+ using size_type = std::common_type_t<std::ranges::range_size_t<decltype(bases)>...>;
+ return (static_cast<size_type>(std::ranges::size(bases)) * ...);
+ },
+ bases_);
+ }
+};
+
+template <class... Rs>
+cartesian_product_view(Rs&&...) -> cartesian_product_view<std::views::all_t<Rs>...>;
+
+} // namespace ranges
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANGES_CARTESIAN_PRODUCT_VIEW_H
diff --git a/libcxx/include/ranges b/libcxx/include/ranges
index fa35874265de67..4d97b19f8f89f2 100644
--- a/libcxx/include/ranges
+++ b/libcxx/include/ranges
@@ -422,6 +422,7 @@ namespace std {
#if _LIBCPP_STD_VER >= 23
# include <__ranges/as_rvalue_view.h>
+# include <__ranges/cartesian_product_view.h>
# include <__ranges/chunk_by_view.h>
# include <__ranges/from_range.h>
# include <__ranges/repeat_view.h>
diff --git a/libcxx/test/std/ranges/range.adaptors/range.cartesian.product.view/ctor.pass.cpp b/libcxx/test/std/ranges/range.adaptors/range.cartesian.product.view/ctor.pass.cpp
new file mode 100644
index 00000000000000..72657095c792ef
--- /dev/null
+++ b/libcxx/test/std/ranges/range.adaptors/range.cartesian.product.view/ctor.pass.cpp
@@ -0,0 +1,36 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// std::ranges::cartesian_product_view
+
+#include <cassert>
+#include <ranges>
+
+#include "test_iterators.h"
+
+struct DefaultConstructibleView : std::ranges::view_base {
+ int i_;
+ int* begin();
+ int* end();
+};
+
+constexpr bool test() {
+ { // view | views::as_rvalue
+ // DefaultConstructibleView v{{}, 3};
+ [[maybe_unused]] std::ranges::cartesian_product_view<DefaultConstructibleView> r1;
+ [[maybe_unused]] std::ranges::cartesian_product_view<DefaultConstructibleView, DefaultConstructibleView> r2;
+ }
+ return true;
+}
+
+int main() {
+ test();
+ static_assert(test());
+}
diff --git a/libcxx/test/std/ranges/range.adaptors/range.cartesian.product.view/size.pass.cpp b/libcxx/test/std/ranges/range.adaptors/range.cartesian.product.view/size.pass.cpp
new file mode 100644
index 00000000000000..5486f9416a66bf
--- /dev/null
+++ b/libcxx/test/std/ranges/range.adaptors/range.cartesian.product.view/size.pass.cpp
@@ -0,0 +1,46 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// std::ranges::cartesian_product_view::size
+
+#include <cassert>
+#include <ranges>
+#include <initializer_list>
+
+constexpr bool test() {
+ {
+ using T = std::initializer_list<int>;
+
+ // example taken from: https://en.cppreference.com/w/cpp/ranges/cartesian_product_view/size
+ constexpr static T w = {1};
+ constexpr static T x = {2, 3};
+ constexpr static T y = {4, 5, 6};
+ constexpr static T z = {7, 8, 9, 10, 11, 12, 13};
+
+ constexpr auto ww = std::ranges::views::all(w);
+ constexpr auto xx = std::ranges::views::all(x);
+ constexpr auto yy = std::ranges::views::all(y);
+ constexpr auto zz = std::ranges::views::all(z);
+
+ constexpr auto v = std::ranges::cartesian_product_view(ww, xx, yy, zz);
+
+ assert(v.size() == 42);
+ assert(v.size() == w.size() * x.size() * y.size() * z.size());
+ static_assert(v.size() == 42);
+ static_assert(v.size() == w.size() * x.size() * y.size() * z.size());
+ }
+
+ return true;
+}
+
+int main() {
+ test();
+ static_assert(test());
+}
>From 5d09a65753e081b65638406f8be6b27f98fd769f Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Fri, 4 Oct 2024 20:31:41 +0200
Subject: [PATCH 02/37] non-const size()
---
.../include/__ranges/cartesian_product_view.h | 21 ++++++++++++-------
.../size.pass.cpp | 18 +++++++---------
2 files changed, 21 insertions(+), 18 deletions(-)
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
index 46941b9e1c97dd..59cf31e3503907 100644
--- a/libcxx/include/__ranges/cartesian_product_view.h
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -11,8 +11,8 @@
#include <__config>
#include <__ranges/concepts.h> // forward_range, view, range_size_t, sized_range, ...
-#include <tuple> // apply
-#include <type_traits> // common_type_t
+#include <tuple> // apply
+#include <type_traits> // common_type_t
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
@@ -65,13 +65,20 @@ class cartesian_product_view : public view_interface<cartesian_product_view<Firs
// requires cartesian-product-is-common<const First, const Vs...>;
// constexpr default_sentinel_t end() const noexcept;
- // constexpr see below size()
- // requires cartesian-product-is-sized<First, Vs...>;
- // constexpr see below size() const
- // requires cartesian-product-is-sized<const First, const Vs...>;
- constexpr auto size() const
+ constexpr auto size()
+ requires(sized_range<First> && ... && sized_range<Vs>)
+ {
+ return size_impl();
+ }
+
+ constexpr auto size() const
requires(sized_range<const First> && ... && sized_range<const Vs>)
{
+ return size_impl();
+ }
+
+private:
+ constexpr auto size_impl() const {
return std::apply(
[](auto&&... bases) {
using size_type = std::common_type_t<std::ranges::range_size_t<decltype(bases)>...>;
diff --git a/libcxx/test/std/ranges/range.adaptors/range.cartesian.product.view/size.pass.cpp b/libcxx/test/std/ranges/range.adaptors/range.cartesian.product.view/size.pass.cpp
index 5486f9416a66bf..82ee47997f53b3 100644
--- a/libcxx/test/std/ranges/range.adaptors/range.cartesian.product.view/size.pass.cpp
+++ b/libcxx/test/std/ranges/range.adaptors/range.cartesian.product.view/size.pass.cpp
@@ -15,26 +15,22 @@
#include <initializer_list>
constexpr bool test() {
- {
- using T = std::initializer_list<int>;
-
+ { // testing: constexpr auto size() const
// example taken from: https://en.cppreference.com/w/cpp/ranges/cartesian_product_view/size
- constexpr static T w = {1};
- constexpr static T x = {2, 3};
- constexpr static T y = {4, 5, 6};
- constexpr static T z = {7, 8, 9, 10, 11, 12, 13};
+ constexpr static auto w = {1};
+ constexpr static auto x = {2, 3};
+ constexpr static auto y = {4, 5, 6};
+ constexpr static auto z = {7, 8, 9, 10, 11, 12, 13};
- constexpr auto ww = std::ranges::views::all(w);
+ constexpr auto ww = std::ranges::views::all(w);
constexpr auto xx = std::ranges::views::all(x);
constexpr auto yy = std::ranges::views::all(y);
constexpr auto zz = std::ranges::views::all(z);
constexpr auto v = std::ranges::cartesian_product_view(ww, xx, yy, zz);
-
+
assert(v.size() == 42);
assert(v.size() == w.size() * x.size() * y.size() * z.size());
- static_assert(v.size() == 42);
- static_assert(v.size() == w.size() * x.size() * y.size() * z.size());
}
return true;
>From 3ffdc30e7f2672f182be03e151c5cd66e084c1df Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Fri, 4 Oct 2024 22:56:20 +0200
Subject: [PATCH 03/37] class cartesian_product_view<First, Vs...>::iterator:
ctors
---
.../include/__ranges/cartesian_product_view.h | 97 ++++++++++++++++++-
1 file changed, 96 insertions(+), 1 deletion(-)
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
index 59cf31e3503907..ac879120295047 100644
--- a/libcxx/include/__ranges/cartesian_product_view.h
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -13,6 +13,7 @@
#include <__ranges/concepts.h> // forward_range, view, range_size_t, sized_range, ...
#include <tuple> // apply
#include <type_traits> // common_type_t
+#include <__type_traits/maybe_const.h>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
@@ -31,10 +32,11 @@ template <input_range First, forward_range... Vs>
requires(view<First> && ... && view<Vs>)
class cartesian_product_view : public view_interface<cartesian_product_view<First, Vs...>> {
private:
+public: // fixme: remove me
tuple<First, Vs...> bases_; // exposition only
template <bool Const>
- struct iterator; // exposition only
+ class iterator; // exposition only
public:
constexpr cartesian_product_view() = default;
@@ -88,6 +90,99 @@ class cartesian_product_view : public view_interface<cartesian_product_view<Firs
}
};
+template<input_range First, forward_range... Vs>
+requires (view<First> && ... && view<Vs>)
+template<bool Const>
+class cartesian_product_view<First, Vs...>::iterator {
+
+ // fixme: implement properly. see section 5.2 in paper.
+ template <class... T>
+ using tuple_or_pair = tuple<T...>;
+
+public:
+// using iterator_category = input_iterator_tag;
+// using iterator_concept = see below;
+// using value_type = tuple-or-pair<range_value_t<__maybe_const<Const, First>>,
+// range_value_t<__maybe_const<Const, Vs>>...>;
+// using reference = tuple-or-pair<reference_t<__maybe_const<Const, First>>,
+// reference_t<__maybe_const<Const, Vs>>...>;
+// using difference_type = see below;
+
+ iterator() requires forward_range<__maybe_const<Const, First>> = default;
+
+ constexpr explicit iterator(tuple_or_pair<iterator_t<__maybe_const<Const, First>>,
+ iterator_t<__maybe_const<Const, Vs>>...> current)
+ : current_(std::move(current)) {}
+
+ constexpr iterator(iterator<!Const> i) requires Const &&
+ (convertible_to<iterator_t<First>, iterator_t<__maybe_const<Const, First>>> &&
+ ... && convertible_to<iterator_t<Vs>, iterator_t<__maybe_const<Const, Vs>>>)
+ : current_(std::move(i.current_)) {}
+
+// constexpr auto operator*() const;
+// constexpr iterator& operator++();
+// constexpr void operator++(int);
+// constexpr iterator operator++(int) requires forward_range<__maybe_const<Const, First>>;
+
+// constexpr iterator& operator--()
+// requires cartesian-product-is-bidirectional<Const, First, Vs...>;
+// constexpr iterator operator--(int)
+// requires cartesian-product-is-bidirectional<Const, First, Vs...>;
+
+// constexpr iterator& operator+=(difference_type x)
+// requires cartesian-product-is-random-access<Const, First, Vs...>;
+// constexpr iterator& operator-=(difference_type x)
+// requires cartesian-product-is-random-access<Const, First, Vs...>;
+
+// constexpr reference operator[](difference_type n) const
+// requires cartesian-product-is-random-access<Const, First, Vs...>;
+
+// friend constexpr bool operator==(const iterator& x, const iterator& y)
+// requires equality_comparable<iterator_t<__maybe_const<Const, First>>>;
+
+// friend constexpr bool operator==(const iterator& x, default_sentinel_t);
+
+// friend constexpr auto operator<=>(const iterator& x, const iterator& y)
+// requires all-random-access<Const, First, Vs...>;
+
+// friend constexpr iterator operator+(const iterator& x, difference_type y)
+// requires cartesian-product-is-random-access<Const, First, Vs...>;
+// friend constexpr iterator operator+(difference_type x, const iterator& y)
+// requires cartesian-product-is-random-access<Const, First, Vs...>;
+// friend constexpr iterator operator-(const iterator& x, difference_type y)
+// requires cartesian-product-is-random-access<Const, First, Vs...>;
+// friend constexpr difference_type operator-(const iterator& x, const iterator& y)
+// requires cartesian-is-sized-sentinel<Const, iterator_t, First, Vs...>;
+
+// friend constexpr difference_type operator-(iterator i, default_sentinel_t)
+// requires cartesian-is-sized-sentinel<Const, sentinel_t, First, Vs...>;
+// friend constexpr difference_type operator-(default_sentinel_t, iterator i)
+// requires cartesian-is-sized-sentinel<Const, sentinel_t, First, Vs...>;
+
+// friend constexpr auto iter_move(const iterator& i) noexcept(see below);
+
+// friend constexpr void iter_swap(const iterator& l, const iterator& r) noexcept(see below)
+// requires (indirectly_swappable<iterator_t<__maybe_const<Const, First>>> && ... &&
+// indirectly_swappable<iterator_t<__maybe_const<Const, Vs>>>);
+
+private:
+// __maybe_const<Const, cartesian_product_view>* parent_ = nullptr; // exposition only
+ tuple_or_pair<iterator_t<__maybe_const<Const, First>>,
+ iterator_t<__maybe_const<Const, Vs>>...> current_; // exposition only
+
+// template <size_t N = sizeof...(Vs)>
+// constexpr void next(); // exposition only
+
+// template <size_t N = sizeof...(Vs)>
+// constexpr void prev(); // exposition only
+
+// template <class Tuple>
+// constexpr difference_type distance-from(Tuple t); // exposition only
+
+// constexpr explicit iterator(tuple-or-pair<iterator_t<__maybe_const<Const, First>>,
+// iterator_t<__maybe_const<Const, Vs>>...> current); // exposition only
+};
+
template <class... Rs>
cartesian_product_view(Rs&&...) -> cartesian_product_view<std::views::all_t<Rs>...>;
>From 7e80ce681d2393eaa43a94aa1bb02ba122ab7d86 Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Fri, 4 Oct 2024 23:16:15 +0200
Subject: [PATCH 04/37] cleanup
---
.../include/__ranges/cartesian_product_view.h | 137 +++---------------
1 file changed, 22 insertions(+), 115 deletions(-)
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
index ac879120295047..811693f3749ce4 100644
--- a/libcxx/include/__ranges/cartesian_product_view.h
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -11,9 +11,9 @@
#include <__config>
#include <__ranges/concepts.h> // forward_range, view, range_size_t, sized_range, ...
-#include <tuple> // apply
-#include <type_traits> // common_type_t
#include <__type_traits/maybe_const.h>
+#include <tuple> // apply
+#include <type_traits> // common_type_t
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
@@ -32,41 +32,18 @@ template <input_range First, forward_range... Vs>
requires(view<First> && ... && view<Vs>)
class cartesian_product_view : public view_interface<cartesian_product_view<First, Vs...>> {
private:
+
public: // fixme: remove me
- tuple<First, Vs...> bases_; // exposition only
+ tuple<First, Vs...> bases_;
template <bool Const>
- class iterator; // exposition only
+ class iterator;
public:
constexpr cartesian_product_view() = default;
constexpr explicit cartesian_product_view(First first_base, Vs... bases)
: bases_{std::move(first_base), std::move(bases)...} {}
- // constexpr iterator<false> begin()
- // requires (!simple-view<First> || ... || !simple-view<Vs>)
- // {
- // return move_iterator(ranges::begin(bases_));
- // }
-
- // constexpr iterator<true> begin() const
- // requires (range<const First> && ... && range<const Vs>)
- // {
- // return move_iterator(ranges::begin(__base_));
- // }
-
- // constexpr iterator<false> begin()
- // requires (!simple-view<First> || ... || !simple-view<Vs>);
- // constexpr iterator<true> begin() const
- // requires (range<const First> && ... && range<const Vs>);
-
- // constexpr iterator<false> end()
- // requires ((!simple-view<First> || ... || !simple-view<Vs>) &&
- // cartesian-product-is-common<First, Vs...>);
- // constexpr iterator<true> end() const
- // requires cartesian-product-is-common<const First, const Vs...>;
- // constexpr default_sentinel_t end() const noexcept;
-
constexpr auto size()
requires(sized_range<First> && ... && sized_range<Vs>)
{
@@ -90,102 +67,32 @@ class cartesian_product_view : public view_interface<cartesian_product_view<Firs
}
};
-template<input_range First, forward_range... Vs>
-requires (view<First> && ... && view<Vs>)
-template<bool Const>
-class cartesian_product_view<First, Vs...>::iterator {
-
- // fixme: implement properly. see section 5.2 in paper.
- template <class... T>
- using tuple_or_pair = tuple<T...>;
+template <class... Vs>
+cartesian_product_view(Vs&&...) -> cartesian_product_view<views::all_t<Vs>...>;
+template <input_range First, forward_range... Vs>
+ requires(view<First> && ... && view<Vs>)
+template <bool Const>
+class cartesian_product_view<First, Vs...>::iterator {
public:
-// using iterator_category = input_iterator_tag;
-// using iterator_concept = see below;
-// using value_type = tuple-or-pair<range_value_t<__maybe_const<Const, First>>,
-// range_value_t<__maybe_const<Const, Vs>>...>;
-// using reference = tuple-or-pair<reference_t<__maybe_const<Const, First>>,
-// reference_t<__maybe_const<Const, Vs>>...>;
-// using difference_type = see below;
-
- iterator() requires forward_range<__maybe_const<Const, First>> = default;
-
- constexpr explicit iterator(tuple_or_pair<iterator_t<__maybe_const<Const, First>>,
- iterator_t<__maybe_const<Const, Vs>>...> current)
+ iterator()
+ requires forward_range<__maybe_const<Const, First>>
+ = default;
+
+ constexpr explicit iterator(
+ tuple<iterator_t<__maybe_const<Const, First>>, iterator_t<__maybe_const<Const, Vs>>...> current)
: current_(std::move(current)) {}
- constexpr iterator(iterator<!Const> i) requires Const &&
- (convertible_to<iterator_t<First>, iterator_t<__maybe_const<Const, First>>> &&
- ... && convertible_to<iterator_t<Vs>, iterator_t<__maybe_const<Const, Vs>>>)
+ constexpr iterator(iterator<!Const> i)
+ requires Const && (convertible_to<iterator_t<First>, iterator_t<__maybe_const<Const, First>>> && ... &&
+ convertible_to<iterator_t<Vs>, iterator_t<__maybe_const<Const, Vs>>>)
: current_(std::move(i.current_)) {}
-// constexpr auto operator*() const;
-// constexpr iterator& operator++();
-// constexpr void operator++(int);
-// constexpr iterator operator++(int) requires forward_range<__maybe_const<Const, First>>;
-
-// constexpr iterator& operator--()
-// requires cartesian-product-is-bidirectional<Const, First, Vs...>;
-// constexpr iterator operator--(int)
-// requires cartesian-product-is-bidirectional<Const, First, Vs...>;
-
-// constexpr iterator& operator+=(difference_type x)
-// requires cartesian-product-is-random-access<Const, First, Vs...>;
-// constexpr iterator& operator-=(difference_type x)
-// requires cartesian-product-is-random-access<Const, First, Vs...>;
-
-// constexpr reference operator[](difference_type n) const
-// requires cartesian-product-is-random-access<Const, First, Vs...>;
-
-// friend constexpr bool operator==(const iterator& x, const iterator& y)
-// requires equality_comparable<iterator_t<__maybe_const<Const, First>>>;
-
-// friend constexpr bool operator==(const iterator& x, default_sentinel_t);
-
-// friend constexpr auto operator<=>(const iterator& x, const iterator& y)
-// requires all-random-access<Const, First, Vs...>;
-
-// friend constexpr iterator operator+(const iterator& x, difference_type y)
-// requires cartesian-product-is-random-access<Const, First, Vs...>;
-// friend constexpr iterator operator+(difference_type x, const iterator& y)
-// requires cartesian-product-is-random-access<Const, First, Vs...>;
-// friend constexpr iterator operator-(const iterator& x, difference_type y)
-// requires cartesian-product-is-random-access<Const, First, Vs...>;
-// friend constexpr difference_type operator-(const iterator& x, const iterator& y)
-// requires cartesian-is-sized-sentinel<Const, iterator_t, First, Vs...>;
-
-// friend constexpr difference_type operator-(iterator i, default_sentinel_t)
-// requires cartesian-is-sized-sentinel<Const, sentinel_t, First, Vs...>;
-// friend constexpr difference_type operator-(default_sentinel_t, iterator i)
-// requires cartesian-is-sized-sentinel<Const, sentinel_t, First, Vs...>;
-
-// friend constexpr auto iter_move(const iterator& i) noexcept(see below);
-
-// friend constexpr void iter_swap(const iterator& l, const iterator& r) noexcept(see below)
-// requires (indirectly_swappable<iterator_t<__maybe_const<Const, First>>> && ... &&
-// indirectly_swappable<iterator_t<__maybe_const<Const, Vs>>>);
-
private:
-// __maybe_const<Const, cartesian_product_view>* parent_ = nullptr; // exposition only
- tuple_or_pair<iterator_t<__maybe_const<Const, First>>,
- iterator_t<__maybe_const<Const, Vs>>...> current_; // exposition only
-
-// template <size_t N = sizeof...(Vs)>
-// constexpr void next(); // exposition only
-
-// template <size_t N = sizeof...(Vs)>
-// constexpr void prev(); // exposition only
-
-// template <class Tuple>
-// constexpr difference_type distance-from(Tuple t); // exposition only
-
-// constexpr explicit iterator(tuple-or-pair<iterator_t<__maybe_const<Const, First>>,
-// iterator_t<__maybe_const<Const, Vs>>...> current); // exposition only
+ // __maybe_const<Const, cartesian_product_view>* parent_ = nullptr;
+ tuple<iterator_t<__maybe_const<Const, First>>, iterator_t<__maybe_const<Const, Vs>>...> current_;
};
-template <class... Rs>
-cartesian_product_view(Rs&&...) -> cartesian_product_view<std::views::all_t<Rs>...>;
-
} // namespace ranges
_LIBCPP_END_NAMESPACE_STD
>From f318b23f2d2cd86c4f052134a59e9ac9f77cc376 Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Fri, 4 Oct 2024 23:24:02 +0200
Subject: [PATCH 05/37] cartesian_product_view::iterator parent member
---
.../include/__ranges/cartesian_product_view.h | 18 +++++++-----------
1 file changed, 7 insertions(+), 11 deletions(-)
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
index 811693f3749ce4..bd0302f7f197d9 100644
--- a/libcxx/include/__ranges/cartesian_product_view.h
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -10,6 +10,7 @@
#define _LIBCPP___RANGES_CARTESIAN_PRODUCT_VIEW_H
#include <__config>
+#include <__memory/addressof.h>
#include <__ranges/concepts.h> // forward_range, view, range_size_t, sized_range, ...
#include <__type_traits/maybe_const.h>
#include <tuple> // apply
@@ -75,21 +76,16 @@ template <input_range First, forward_range... Vs>
template <bool Const>
class cartesian_product_view<First, Vs...>::iterator {
public:
- iterator()
- requires forward_range<__maybe_const<Const, First>>
- = default;
-
- constexpr explicit iterator(
- tuple<iterator_t<__maybe_const<Const, First>>, iterator_t<__maybe_const<Const, Vs>>...> current)
- : current_(std::move(current)) {}
+ iterator() = default;
constexpr iterator(iterator<!Const> i)
- requires Const && (convertible_to<iterator_t<First>, iterator_t<__maybe_const<Const, First>>> && ... &&
- convertible_to<iterator_t<Vs>, iterator_t<__maybe_const<Const, Vs>>>)
- : current_(std::move(i.current_)) {}
+ requires Const && (convertible_to<iterator_t<First>, iterator_t<const First>> && ... &&
+ convertible_to<iterator_t<Vs>, iterator_t<const Vs>>)
+ : parent_(std::addressof(i.parent_)), current_(std::move(i.current_)) {}
private:
- // __maybe_const<Const, cartesian_product_view>* parent_ = nullptr;
+ using Parent = __maybe_const<Const, cartesian_product_view>;
+ Parent* parent_ = nullptr;
tuple<iterator_t<__maybe_const<Const, First>>, iterator_t<__maybe_const<Const, Vs>>...> current_;
};
>From 72ba4530d4333596782b235ac9d78937164a2e24 Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Fri, 4 Oct 2024 23:31:03 +0200
Subject: [PATCH 06/37] iterator: private ctor
---
libcxx/include/__ranges/cartesian_product_view.h | 3 +++
1 file changed, 3 insertions(+)
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
index bd0302f7f197d9..f330f186e72b83 100644
--- a/libcxx/include/__ranges/cartesian_product_view.h
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -87,6 +87,9 @@ class cartesian_product_view<First, Vs...>::iterator {
using Parent = __maybe_const<Const, cartesian_product_view>;
Parent* parent_ = nullptr;
tuple<iterator_t<__maybe_const<Const, First>>, iterator_t<__maybe_const<Const, Vs>>...> current_;
+
+ constexpr iterator(Parent& parent, decltype(current_) current)
+ : parent_(std::addressof(parent)), current_(std::move(current)) {}
};
} // namespace ranges
>From a9ff49b5796574f4a07e20eac7477d8042a93f75 Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Fri, 4 Oct 2024 23:34:55 +0200
Subject: [PATCH 07/37] iterator: tags
---
libcxx/include/__ranges/cartesian_product_view.h | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
index f330f186e72b83..65111a7f827426 100644
--- a/libcxx/include/__ranges/cartesian_product_view.h
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -76,6 +76,11 @@ template <input_range First, forward_range... Vs>
template <bool Const>
class cartesian_product_view<First, Vs...>::iterator {
public:
+ using iterator_category = input_iterator_tag;
+ using value_type = tuple<range_value_t<__maybe_const<Const, First>>, range_value_t<__maybe_const<Const, Vs>>...>;
+ using reference =
+ tuple<range_reference_t<__maybe_const<Const, First>>, range_reference_t<__maybe_const<Const, Vs>>...>;
+
iterator() = default;
constexpr iterator(iterator<!Const> i)
>From a6b0981dbe86513309446575212e36b5f839d18f Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Fri, 4 Oct 2024 23:44:10 +0200
Subject: [PATCH 08/37] iterator: operator*()
---
libcxx/include/__ranges/cartesian_product_view.h | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
index 65111a7f827426..16fe28a6122c92 100644
--- a/libcxx/include/__ranges/cartesian_product_view.h
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -12,6 +12,7 @@
#include <__config>
#include <__memory/addressof.h>
#include <__ranges/concepts.h> // forward_range, view, range_size_t, sized_range, ...
+#include <__ranges/zip_view.h> // tuple_transform
#include <__type_traits/maybe_const.h>
#include <tuple> // apply
#include <type_traits> // common_type_t
@@ -88,6 +89,10 @@ class cartesian_product_view<First, Vs...>::iterator {
convertible_to<iterator_t<Vs>, iterator_t<const Vs>>)
: parent_(std::addressof(i.parent_)), current_(std::move(i.current_)) {}
+ constexpr auto operator*() const {
+ return __tuple_transform([](auto& i) -> decltype(auto) { return *i; }, current_);
+ }
+
private:
using Parent = __maybe_const<Const, cartesian_product_view>;
Parent* parent_ = nullptr;
>From 3cab3df41fd023b3c3608b61d90abb01dc575790 Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Sat, 5 Oct 2024 22:27:46 +0200
Subject: [PATCH 09/37] add to modulemap
---
libcxx/include/module.modulemap | 1 +
1 file changed, 1 insertion(+)
diff --git a/libcxx/include/module.modulemap b/libcxx/include/module.modulemap
index 881c0ca6c3669c..dc307c9c5600f8 100644
--- a/libcxx/include/module.modulemap
+++ b/libcxx/include/module.modulemap
@@ -1673,6 +1673,7 @@ module std [system] {
module access { header "__ranges/access.h" }
module all { header "__ranges/all.h" }
module as_rvalue_view { header "__ranges/as_rvalue_view.h" }
+ module cartesian_product_view { header "__ranges/cartesian_product_view.h" }
module chunk_by_view {
header "__ranges/chunk_by_view.h"
export std.functional.bind_back
>From db0a2be20d6126255732d07fd67c15b0571f13fa Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Sat, 5 Oct 2024 22:46:25 +0200
Subject: [PATCH 10/37] iterator: operator++(), next()
---
.../include/__ranges/cartesian_product_view.h | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
index 16fe28a6122c92..7218da2906a8c1 100644
--- a/libcxx/include/__ranges/cartesian_product_view.h
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -10,6 +10,7 @@
#define _LIBCPP___RANGES_CARTESIAN_PRODUCT_VIEW_H
#include <__config>
+#include <__iterator/access.h> // begin
#include <__memory/addressof.h>
#include <__ranges/concepts.h> // forward_range, view, range_size_t, sized_range, ...
#include <__ranges/zip_view.h> // tuple_transform
@@ -93,6 +94,11 @@ class cartesian_product_view<First, Vs...>::iterator {
return __tuple_transform([](auto& i) -> decltype(auto) { return *i; }, current_);
}
+ constexpr iterator& operator++() {
+ next();
+ return *this;
+ }
+
private:
using Parent = __maybe_const<Const, cartesian_product_view>;
Parent* parent_ = nullptr;
@@ -100,6 +106,18 @@ class cartesian_product_view<First, Vs...>::iterator {
constexpr iterator(Parent& parent, decltype(current_) current)
: parent_(std::addressof(parent)), current_(std::move(current)) {}
+
+ template <auto N = sizeof...(Vs)>
+ constexpr void next() {
+ const auto& v = std::get<N>(parent_->bases_);
+ auto& it = std::get<N>(current_);
+ if (++it == std::end(v)) {
+ if constexpr (N != 0) {
+ it = std::ranges::begin(v);
+ next<N - 1>();
+ }
+ }
+ }
};
} // namespace ranges
>From 1b5c94f914e40ea659dc51be6a328bf3eae40be0 Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Sat, 5 Oct 2024 23:05:50 +0200
Subject: [PATCH 11/37] iterator: operator++(int)
---
libcxx/include/__ranges/cartesian_product_view.h | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
index 7218da2906a8c1..fd2d3f4e099804 100644
--- a/libcxx/include/__ranges/cartesian_product_view.h
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -99,6 +99,16 @@ class cartesian_product_view<First, Vs...>::iterator {
return *this;
}
+ constexpr void operator++(int) { next(); }
+
+ constexpr iterator operator++(int)
+ requires forward_range<__maybe_const<Const, First>>
+ {
+ auto tmp = *this;
+ next();
+ return tmp;
+ }
+
private:
using Parent = __maybe_const<Const, cartesian_product_view>;
Parent* parent_ = nullptr;
>From d11813e06a8eb6a288008c4fd1f9a96aaa5e5b4f Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Sat, 5 Oct 2024 23:38:28 +0200
Subject: [PATCH 12/37] iterator: operator--(), prev(); concepts
---
.../include/__ranges/cartesian_product_view.h | 40 +++++++++++++++++--
1 file changed, 37 insertions(+), 3 deletions(-)
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
index fd2d3f4e099804..586dcde42c6f47 100644
--- a/libcxx/include/__ranges/cartesian_product_view.h
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -31,12 +31,27 @@ _LIBCPP_BEGIN_NAMESPACE_STD
namespace ranges {
+template <class R>
+concept cartesian_product_common_arg = common_range<R> || (sized_range<R> && random_access_range<R>);
+
+template <bool Const, class First, class... Vs>
+concept cartesian_product_is_bidirectional =
+ (bidirectional_range<__maybe_const<Const, First>> && ... &&
+ (bidirectional_range<__maybe_const<Const, Vs>> && cartesian_product_common_arg<__maybe_const<Const, Vs>>));
+
+template <cartesian_product_common_arg R>
+constexpr auto cartesian_common_arg_end(R& r) {
+ if constexpr (common_range<R>) {
+ return ranges::end(r);
+ } else {
+ return ranges::begin(r) + ranges::distance(r);
+ }
+}
+
template <input_range First, forward_range... Vs>
requires(view<First> && ... && view<Vs>)
class cartesian_product_view : public view_interface<cartesian_product_view<First, Vs...>> {
-private:
-
-public: // fixme: remove me
+public: // fixme: make private
tuple<First, Vs...> bases_;
template <bool Const>
@@ -109,6 +124,13 @@ class cartesian_product_view<First, Vs...>::iterator {
return tmp;
}
+ constexpr iterator& operator--()
+ requires cartesian_product_is_bidirectional<Const, First, Vs...>
+ {
+ prev();
+ return *this;
+ }
+
private:
using Parent = __maybe_const<Const, cartesian_product_view>;
Parent* parent_ = nullptr;
@@ -128,6 +150,18 @@ class cartesian_product_view<First, Vs...>::iterator {
}
}
}
+
+ template <auto N = sizeof...(Vs)>
+ constexpr void prev() {
+ auto& it = std::get<N>(current_);
+ if constexpr (N > 0) {
+ if (const auto& v = std::get<N>(parent_->bases_); it == ranges::begin(v)) {
+ it = cartesian_common_arg_end(v);
+ prev<N - 1>();
+ }
+ }
+ --it;
+ }
};
} // namespace ranges
>From bf48c4963c1159bb703039251c5937d479b71905 Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Sat, 5 Oct 2024 23:41:32 +0200
Subject: [PATCH 13/37] iterator: next() as suggested in std
---
libcxx/include/__ranges/cartesian_product_view.h | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
index 586dcde42c6f47..8fb4a09d4e8d22 100644
--- a/libcxx/include/__ranges/cartesian_product_view.h
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -141,11 +141,11 @@ class cartesian_product_view<First, Vs...>::iterator {
template <auto N = sizeof...(Vs)>
constexpr void next() {
- const auto& v = std::get<N>(parent_->bases_);
- auto& it = std::get<N>(current_);
- if (++it == std::end(v)) {
- if constexpr (N != 0) {
- it = std::ranges::begin(v);
+ auto& it = std::get<N>(current_);
+ ++it;
+ if constexpr (N > 0) {
+ if (const auto& v = std::get<N>(parent_->bases_); it == ranges::end(v)) {
+ it = ranges::begin(v);
next<N - 1>();
}
}
>From 5aed102f15ddaea2c4de813a81fb2fa102278b8b Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Sat, 5 Oct 2024 23:43:36 +0200
Subject: [PATCH 14/37] iterator: operator--(int)
---
libcxx/include/__ranges/cartesian_product_view.h | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
index 8fb4a09d4e8d22..4f6fded8c74b3d 100644
--- a/libcxx/include/__ranges/cartesian_product_view.h
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -131,6 +131,13 @@ class cartesian_product_view<First, Vs...>::iterator {
return *this;
}
+ constexpr iterator operator--(int)
+requires cartesian_product_is_bidirectional <Const, First, Vs...> {
+ auto tmp = *this;
+ prev();
+ return tmp;
+}
+
private:
using Parent = __maybe_const<Const, cartesian_product_view>;
Parent* parent_ = nullptr;
>From e234275ce31d38127d4abae670725dc79bc182e5 Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Sun, 6 Oct 2024 00:11:27 +0200
Subject: [PATCH 15/37] iterator: operator+=(x), -=(x); concept
---
.../include/__ranges/cartesian_product_view.h | 58 ++++++++++++++++++-
1 file changed, 55 insertions(+), 3 deletions(-)
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
index 4f6fded8c74b3d..495ec1fd63e51e 100644
--- a/libcxx/include/__ranges/cartesian_product_view.h
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -31,6 +31,11 @@ _LIBCPP_BEGIN_NAMESPACE_STD
namespace ranges {
+template <bool Const, class First, class... Vs>
+concept cartesian_product_is_random_access =
+ (random_access_range<__maybe_const<Const, First>> && ... &&
+ (random_access_range<__maybe_const<Const, Vs>> && sized_range<__maybe_const<Const, Vs>>));
+
template <class R>
concept cartesian_product_common_arg = common_range<R> || (sized_range<R> && random_access_range<R>);
@@ -97,6 +102,7 @@ class cartesian_product_view<First, Vs...>::iterator {
using value_type = tuple<range_value_t<__maybe_const<Const, First>>, range_value_t<__maybe_const<Const, Vs>>...>;
using reference =
tuple<range_reference_t<__maybe_const<Const, First>>, range_reference_t<__maybe_const<Const, Vs>>...>;
+ using difference_type = std::common_type_t<range_difference_t<First>, range_difference_t<Vs>...>;
iterator() = default;
@@ -132,11 +138,26 @@ class cartesian_product_view<First, Vs...>::iterator {
}
constexpr iterator operator--(int)
-requires cartesian_product_is_bidirectional <Const, First, Vs...> {
- auto tmp = *this;
+ requires cartesian_product_is_bidirectional<Const, First, Vs...>
+ {
+ auto tmp = *this;
prev();
return tmp;
-}
+ }
+
+ constexpr iterator& operator+=(difference_type x)
+ requires cartesian_product_is_random_access<Const, First, Vs...>
+ {
+ advance(x);
+ return *this;
+ }
+
+ constexpr iterator& operator-=(difference_type x)
+ requires cartesian_product_is_random_access<Const, First, Vs...>
+ {
+ advance(x);
+ return *this;
+ }
private:
using Parent = __maybe_const<Const, cartesian_product_view>;
@@ -169,6 +190,37 @@ requires cartesian_product_is_bidirectional <Const, First, Vs...> {
}
--it;
}
+
+ template <std::size_t N = sizeof...(Vs)>
+ constexpr void advance(difference_type x) {
+ if (x == 0)
+ return;
+
+ const auto& v = std::get<N>(parent_->bases_);
+ auto& it = std::get<N>(current_);
+ const auto sz = static_cast<difference_type>(std::ranges::size(v));
+ const auto first = begin(v);
+
+ const auto idx = static_cast<difference_type>(it - first);
+ x += idx;
+
+ auto div = sz ? x / sz : 0;
+ auto mod = sz ? x % sz : 0;
+
+ if constexpr (N != 0) {
+ if (mod < 0) {
+ mod += sz;
+ div--;
+ }
+ advance<N - 1>(div);
+ } else {
+ if (div > 0) {
+ mod = sz;
+ }
+ }
+ using D = std::iter_difference_t<decltype(first)>;
+ it = first + static_cast<D>(mod);
+ }
};
} // namespace ranges
>From eafa9b765ceb2b057423b834294a922b14b461db Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Fri, 11 Oct 2024 22:33:21 +0200
Subject: [PATCH 16/37] cleanup of iterator: operator+=(x), -=(x)
---
.../include/__ranges/cartesian_product_view.h | 39 +++++++++++--------
1 file changed, 23 insertions(+), 16 deletions(-)
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
index 495ec1fd63e51e..aca22153e1366e 100644
--- a/libcxx/include/__ranges/cartesian_product_view.h
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -11,6 +11,8 @@
#include <__config>
#include <__iterator/access.h> // begin
+#include <__iterator/distance.h>
+#include <__iterator/next.h>
#include <__memory/addressof.h>
#include <__ranges/concepts.h> // forward_range, view, range_size_t, sized_range, ...
#include <__ranges/zip_view.h> // tuple_transform
@@ -155,7 +157,7 @@ class cartesian_product_view<First, Vs...>::iterator {
constexpr iterator& operator-=(difference_type x)
requires cartesian_product_is_random_access<Const, First, Vs...>
{
- advance(x);
+ *this += -x;
return *this;
}
@@ -201,25 +203,30 @@ class cartesian_product_view<First, Vs...>::iterator {
const auto sz = static_cast<difference_type>(std::ranges::size(v));
const auto first = begin(v);
- const auto idx = static_cast<difference_type>(it - first);
- x += idx;
-
- auto div = sz ? x / sz : 0;
- auto mod = sz ? x % sz : 0;
-
- if constexpr (N != 0) {
- if (mod < 0) {
- mod += sz;
- div--;
+ if (sz > 0) {
+ const auto idx = static_cast<difference_type>(std::distance(first, it));
+ x += idx;
+
+ difference_type mod;
+ if constexpr (N > 0) {
+ difference_type div = x / sz;
+ mod = x % sz;
+ if (mod < 0) {
+ mod += sz;
+ div--;
+ }
+ advance<N - 1>(div);
+ } else {
+ mod = (x >= 0 && x < sz) ? x : sz;
}
- advance<N - 1>(div);
+ it = std::next(first, mod);
+
} else {
- if (div > 0) {
- mod = sz;
+ if constexpr (N > 0) {
+ advance<N - 1>(x);
}
+ it = first;
}
- using D = std::iter_difference_t<decltype(first)>;
- it = first + static_cast<D>(mod);
}
};
>From 4090501d4888cce43e1189c0916a6e0e862506a3 Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Fri, 11 Oct 2024 22:37:41 +0200
Subject: [PATCH 17/37] iterator: operator[](n)
---
libcxx/include/__ranges/cartesian_product_view.h | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
index aca22153e1366e..0f9f825dba5e6c 100644
--- a/libcxx/include/__ranges/cartesian_product_view.h
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -161,6 +161,12 @@ class cartesian_product_view<First, Vs...>::iterator {
return *this;
}
+ constexpr reference operator[](difference_type n) const
+ requires cartesian_product_is_random_access<Const, First, Vs...>
+ {
+ return *((*this) + n);
+ }
+
private:
using Parent = __maybe_const<Const, cartesian_product_view>;
Parent* parent_ = nullptr;
>From 30744d92dcb38fb043b64890b546a3915b50cd59 Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Fri, 11 Oct 2024 22:40:28 +0200
Subject: [PATCH 18/37] iterator: operator==(iterator, iterator)
---
libcxx/include/__ranges/cartesian_product_view.h | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
index 0f9f825dba5e6c..bf533ebc59aa96 100644
--- a/libcxx/include/__ranges/cartesian_product_view.h
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -167,6 +167,12 @@ class cartesian_product_view<First, Vs...>::iterator {
return *((*this) + n);
}
+ friend constexpr bool operator==(const iterator& x, const iterator& y)
+ requires equality_comparable<iterator_t<__maybe_const<Const, First>>>
+ {
+ return x.current_ == y.current_;
+ }
+
private:
using Parent = __maybe_const<Const, cartesian_product_view>;
Parent* parent_ = nullptr;
>From d38953907bba91df2ac1f55816da23cbae145cae Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Fri, 11 Oct 2024 22:56:55 +0200
Subject: [PATCH 19/37] iterator: operator==(iterator, sentinel)
---
libcxx/include/__ranges/cartesian_product_view.h | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
index bf533ebc59aa96..191fe44433270b 100644
--- a/libcxx/include/__ranges/cartesian_product_view.h
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -173,6 +173,8 @@ class cartesian_product_view<First, Vs...>::iterator {
return x.current_ == y.current_;
}
+ friend constexpr bool operator==(const iterator& x, default_sentinel_t) { return x.at_end(); }
+
private:
using Parent = __maybe_const<Const, cartesian_product_view>;
Parent* parent_ = nullptr;
@@ -240,6 +242,15 @@ class cartesian_product_view<First, Vs...>::iterator {
it = first;
}
}
+
+ template <auto N = sizeof...(Vs)>
+ constexpr bool at_end() const {
+ if (std::get<N>(current_) == end(std::get<N>(parent_->bases_)))
+ return true;
+ if constexpr (N > 0)
+ return at_end<N - 1>();
+ return false;
+ }
};
} // namespace ranges
>From b6347518ad1c779d40ca5c68c6c9fc7ff2ff6f9a Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Fri, 11 Oct 2024 23:08:14 +0200
Subject: [PATCH 20/37] iterator: operator<=>(iterator, iterator); concept
---
libcxx/include/__ranges/cartesian_product_view.h | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
index 191fe44433270b..c4428845e2c5c3 100644
--- a/libcxx/include/__ranges/cartesian_product_view.h
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -55,6 +55,10 @@ constexpr auto cartesian_common_arg_end(R& r) {
}
}
+template <bool Const, class First, class... Vs>
+concept __cartesian_product_all_random_access =
+ (random_access_range<__maybe_const<Const, First>> && ... && random_access_range<__maybe_const<Const, Vs>>);
+
template <input_range First, forward_range... Vs>
requires(view<First> && ... && view<Vs>)
class cartesian_product_view : public view_interface<cartesian_product_view<First, Vs...>> {
@@ -175,6 +179,12 @@ class cartesian_product_view<First, Vs...>::iterator {
friend constexpr bool operator==(const iterator& x, default_sentinel_t) { return x.at_end(); }
+ friend constexpr auto operator<=>(const iterator& x, const iterator& y)
+ requires __cartesian_product_all_random_access<Const, First, Vs...>
+ {
+ return x.current_ <=> y.current_;
+ }
+
private:
using Parent = __maybe_const<Const, cartesian_product_view>;
Parent* parent_ = nullptr;
>From 0edb1f46bd0056f1c517af23f468ff406884790c Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Fri, 11 Oct 2024 23:10:24 +0200
Subject: [PATCH 21/37] iterator: operator+(iterator, diffType)
---
libcxx/include/__ranges/cartesian_product_view.h | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
index c4428845e2c5c3..329e9787062467 100644
--- a/libcxx/include/__ranges/cartesian_product_view.h
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -185,6 +185,12 @@ class cartesian_product_view<First, Vs...>::iterator {
return x.current_ <=> y.current_;
}
+ friend constexpr iterator operator+(const iterator& x, difference_type y)
+ requires cartesian_product_is_random_access<Const, First, Vs...>
+ {
+ return iterator(x) += y;
+ }
+
private:
using Parent = __maybe_const<Const, cartesian_product_view>;
Parent* parent_ = nullptr;
>From 14ac91f588c043e63206973d12a83a5de37b0cd2 Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Fri, 11 Oct 2024 23:11:41 +0200
Subject: [PATCH 22/37] iterator: operator+(diffType, iterator)
---
libcxx/include/__ranges/cartesian_product_view.h | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
index 329e9787062467..d2ed56d2a8ae1d 100644
--- a/libcxx/include/__ranges/cartesian_product_view.h
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -191,6 +191,12 @@ class cartesian_product_view<First, Vs...>::iterator {
return iterator(x) += y;
}
+ friend constexpr iterator operator+(difference_type x, const iterator& y)
+ requires cartesian_product_is_random_access<Const, First, Vs...>
+ {
+ return y + x;
+ }
+
private:
using Parent = __maybe_const<Const, cartesian_product_view>;
Parent* parent_ = nullptr;
>From 35dbac4ebb8ecfea7cb9b82488eac26893acbcae Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Fri, 11 Oct 2024 23:13:52 +0200
Subject: [PATCH 23/37] iterator: operator-(iterator, diffType)
---
libcxx/include/__ranges/cartesian_product_view.h | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
index d2ed56d2a8ae1d..8c09e2b097df9a 100644
--- a/libcxx/include/__ranges/cartesian_product_view.h
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -197,6 +197,12 @@ class cartesian_product_view<First, Vs...>::iterator {
return y + x;
}
+ friend constexpr iterator operator-(const iterator& x, difference_type y)
+ requires cartesian_product_is_random_access<Const, First, Vs...>
+ {
+ return iterator(x) -= y;
+ }
+
private:
using Parent = __maybe_const<Const, cartesian_product_view>;
Parent* parent_ = nullptr;
>From bf4f8dffbdc327a8eb6ff3e07a7d98cd26220963 Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Fri, 11 Oct 2024 23:49:29 +0200
Subject: [PATCH 24/37] iterator: operator-(iterator, iterator); concept
---
.../include/__ranges/cartesian_product_view.h | 36 +++++++++++++++++++
1 file changed, 36 insertions(+)
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
index 8c09e2b097df9a..399c28585b1414 100644
--- a/libcxx/include/__ranges/cartesian_product_view.h
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -46,6 +46,15 @@ concept cartesian_product_is_bidirectional =
(bidirectional_range<__maybe_const<Const, First>> && ... &&
(bidirectional_range<__maybe_const<Const, Vs>> && cartesian_product_common_arg<__maybe_const<Const, Vs>>));
+template <class... Vs>
+concept cartesian_product_is_sized = (sized_range<Vs> && ...);
+
+template <bool Const, template <class> class FirstSent, class First, class... Vs>
+concept cartesian_is_sized_sentinel =
+ (sized_sentinel_for<FirstSent<__maybe_const<Const, First>>, iterator_t<__maybe_const<Const, First>>> && ... &&
+ (sized_range<__maybe_const<Const, Vs>> &&
+ sized_sentinel_for<iterator_t<__maybe_const<Const, Vs>>, iterator_t<__maybe_const<Const, Vs>>>));
+
template <cartesian_product_common_arg R>
constexpr auto cartesian_common_arg_end(R& r) {
if constexpr (common_range<R>) {
@@ -203,6 +212,12 @@ class cartesian_product_view<First, Vs...>::iterator {
return iterator(x) -= y;
}
+ friend constexpr iterator operator-(const iterator& x, const iterator& y)
+ requires cartesian_product_is_random_access<Const, First, Vs...>
+ {
+ return x.distance_from(y.current_);
+ }
+
private:
using Parent = __maybe_const<Const, cartesian_product_view>;
Parent* parent_ = nullptr;
@@ -279,6 +294,27 @@ class cartesian_product_view<First, Vs...>::iterator {
return at_end<N - 1>();
return false;
}
+
+ template <class Tuple>
+ constexpr difference_type distance_from(const Tuple& t) const {
+ constexpr auto seq = std::make_integer_sequence<int, sizeof...(Vs) + 1>{};
+ constexpr auto scaled_sum = [&t, this]<int... Ints>(std::integer_sequence<int, Ints...>) -> difference_type {
+ return (scaled_distance<Ints>(t) + ...);
+ };
+ return scaled_sum(seq);
+ }
+
+ template <auto N>
+ constexpr difference_type scaled_size() const {
+ if constexpr (N <= sizeof...(Vs))
+ return static_cast<difference_type>(ranges::size(std::get<N>(parent_->bases_))) * scaled_size<N + 1>();
+ return static_cast<difference_type>(1);
+ }
+
+ template <auto N, class Tuple>
+ constexpr difference_type scaled_distance(const Tuple& t) const {
+ return static_cast<difference_type>(std::get<N>(current_) - std::get<N>(t)) * scaled_size<N + 1>();
+ }
};
} // namespace ranges
>From 070cd743ec5032edfc6256e8eae79b648258c9f8 Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Sun, 13 Oct 2024 20:13:12 +0200
Subject: [PATCH 25/37] iterator: operator-(iterator, iterator) <cleanup>
---
.../include/__ranges/cartesian_product_view.h | 17 ++++++++++-------
1 file changed, 10 insertions(+), 7 deletions(-)
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
index 399c28585b1414..6cba859d28c573 100644
--- a/libcxx/include/__ranges/cartesian_product_view.h
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -297,11 +297,7 @@ class cartesian_product_view<First, Vs...>::iterator {
template <class Tuple>
constexpr difference_type distance_from(const Tuple& t) const {
- constexpr auto seq = std::make_integer_sequence<int, sizeof...(Vs) + 1>{};
- constexpr auto scaled_sum = [&t, this]<int... Ints>(std::integer_sequence<int, Ints...>) -> difference_type {
- return (scaled_distance<Ints>(t) + ...);
- };
- return scaled_sum(seq);
+ return scaled_sum(t);
}
template <auto N>
@@ -311,10 +307,17 @@ class cartesian_product_view<First, Vs...>::iterator {
return static_cast<difference_type>(1);
}
- template <auto N, class Tuple>
- constexpr difference_type scaled_distance(const Tuple& t) const {
+ template <auto N>
+ constexpr difference_type scaled_distance(const auto& t) const {
return static_cast<difference_type>(std::get<N>(current_) - std::get<N>(t)) * scaled_size<N + 1>();
}
+
+ template <auto N = 0>
+ constexpr difference_type scaled_sum(const auto& t) const {
+ if constexpr (N <= sizeof...(Vs))
+ return scaled_distance<N>(t) + scaled_sum<N + 1>(t);
+ return static_cast<difference_type>(0);
+ }
};
} // namespace ranges
>From 9d243a8b5b5c69bcb48b40abe06806180d488567 Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Sun, 13 Oct 2024 20:26:45 +0200
Subject: [PATCH 26/37] iterator: operator-(iterator, sentinel)
---
libcxx/include/__ranges/cartesian_product_view.h | 13 ++++++++++++-
1 file changed, 12 insertions(+), 1 deletion(-)
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
index 6cba859d28c573..9d56422e65141d 100644
--- a/libcxx/include/__ranges/cartesian_product_view.h
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -218,10 +218,21 @@ class cartesian_product_view<First, Vs...>::iterator {
return x.distance_from(y.current_);
}
+ friend constexpr difference_type operator-(const iterator& i, default_sentinel_t)
+ requires cartesian_is_sized_sentinel<Const, sentinel_t, First, Vs...>
+ {
+ MultiIterator end_tuple;
+ std::get<0>(end_tuple) = ranges::end(std::get<0>(i.parent_->bases_));
+ for (int N = 1; N <= sizeof...(Vs); N++)
+ std::get<N>(end_tuple) = ranges::begin(std::get<N>(i.parent_->bases_));
+ return i.distance_from(end_tuple);
+ }
+
private:
using Parent = __maybe_const<Const, cartesian_product_view>;
Parent* parent_ = nullptr;
- tuple<iterator_t<__maybe_const<Const, First>>, iterator_t<__maybe_const<Const, Vs>>...> current_;
+ using MultiIterator = tuple<iterator_t<__maybe_const<Const, First>>, iterator_t<__maybe_const<Const, Vs>>...>;
+ MultiIterator current_;
constexpr iterator(Parent& parent, decltype(current_) current)
: parent_(std::addressof(parent)), current_(std::move(current)) {}
>From 5d91da30f9d2ee9fa8afe57f0e59cc039409422e Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Sun, 13 Oct 2024 20:28:16 +0200
Subject: [PATCH 27/37] iterator: operator-(sentinel, iterator)
---
libcxx/include/__ranges/cartesian_product_view.h | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
index 9d56422e65141d..e76af70aaf5907 100644
--- a/libcxx/include/__ranges/cartesian_product_view.h
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -228,6 +228,12 @@ class cartesian_product_view<First, Vs...>::iterator {
return i.distance_from(end_tuple);
}
+ friend constexpr difference_type operator-(default_sentinel_t s, const iterator& i)
+ requires cartesian_is_sized_sentinel<Const, sentinel_t, First, Vs...>
+ {
+ return -(i - s);
+ }
+
private:
using Parent = __maybe_const<Const, cartesian_product_view>;
Parent* parent_ = nullptr;
>From 4616f00163df648f3de07c0c1cb0b271850280ff Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Sun, 13 Oct 2024 20:38:16 +0200
Subject: [PATCH 28/37] iterator: iter_move(iterator)
---
libcxx/include/__ranges/cartesian_product_view.h | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
index e76af70aaf5907..a954b2e62aa992 100644
--- a/libcxx/include/__ranges/cartesian_product_view.h
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -12,6 +12,7 @@
#include <__config>
#include <__iterator/access.h> // begin
#include <__iterator/distance.h>
+#include <__iterator/iter_move.h>
#include <__iterator/next.h>
#include <__memory/addressof.h>
#include <__ranges/concepts.h> // forward_range, view, range_size_t, sized_range, ...
@@ -234,6 +235,10 @@ class cartesian_product_view<First, Vs...>::iterator {
return -(i - s);
}
+ friend constexpr auto iter_move(const iterator& i) /*fixme: noexcept(...) */ {
+ return __tuple_transform(ranges::iter_move, i.current_);
+ }
+
private:
using Parent = __maybe_const<Const, cartesian_product_view>;
Parent* parent_ = nullptr;
>From 934613049ff9fbbde42ba0bc311ca185201c5408 Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Sun, 13 Oct 2024 20:46:50 +0200
Subject: [PATCH 29/37] iterator: iter_swap(iterator, iterator)
---
libcxx/include/__ranges/cartesian_product_view.h | 14 ++++++++++++++
1 file changed, 14 insertions(+)
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
index a954b2e62aa992..4903eb4773c00e 100644
--- a/libcxx/include/__ranges/cartesian_product_view.h
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -239,6 +239,13 @@ class cartesian_product_view<First, Vs...>::iterator {
return __tuple_transform(ranges::iter_move, i.current_);
}
+ friend constexpr void iter_swap(const iterator& l, const iterator& r) /*fixme: noexcept(...) */
+ requires(indirectly_swappable<iterator_t<__maybe_const<Const, First>>> && ... &&
+ indirectly_swappable<iterator_t<__maybe_const<Const, Vs>>>)
+ {
+ iter_swap_helper(l, r);
+ }
+
private:
using Parent = __maybe_const<Const, cartesian_product_view>;
Parent* parent_ = nullptr;
@@ -340,6 +347,13 @@ class cartesian_product_view<First, Vs...>::iterator {
return scaled_distance<N>(t) + scaled_sum<N + 1>(t);
return static_cast<difference_type>(0);
}
+
+ template <auto N = sizeof...(Vs)>
+ static constexpr void iter_swap_helper(const iterator& l, const iterator& r) {
+ ranges::iter_swap(std::get<N>(l.current_), std::get<N>(r.current_));
+ if constexpr (N > 0)
+ iter_swap_helper<N - 1>(l, r);
+ }
};
} // namespace ranges
>From 78d97196d44978ce531180c65441406eb9a10642 Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Fri, 18 Oct 2024 22:29:02 +0200
Subject: [PATCH 30/37] concept; style change
---
libcxx/include/__ranges/cartesian_product_view.h | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
index 4903eb4773c00e..035c60a6a94388 100644
--- a/libcxx/include/__ranges/cartesian_product_view.h
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -47,6 +47,9 @@ concept cartesian_product_is_bidirectional =
(bidirectional_range<__maybe_const<Const, First>> && ... &&
(bidirectional_range<__maybe_const<Const, Vs>> && cartesian_product_common_arg<__maybe_const<Const, Vs>>));
+template <class First, class... Vs>
+concept cartesian_product_is_common = cartesian_product_common_arg<First>;
+
template <class... Vs>
concept cartesian_product_is_sized = (sized_range<Vs> && ...);
@@ -72,7 +75,7 @@ concept __cartesian_product_all_random_access =
template <input_range First, forward_range... Vs>
requires(view<First> && ... && view<Vs>)
class cartesian_product_view : public view_interface<cartesian_product_view<First, Vs...>> {
-public: // fixme: make private
+private:
tuple<First, Vs...> bases_;
template <bool Const>
>From aa2c1697d18c123a72bd2d5a592dc3f7561c73d4 Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Fri, 18 Oct 2024 22:30:01 +0200
Subject: [PATCH 31/37] view: begin()
---
libcxx/include/__ranges/cartesian_product_view.h | 14 +++++++++++++-
1 file changed, 13 insertions(+), 1 deletion(-)
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
index 035c60a6a94388..39e53bffecc628 100644
--- a/libcxx/include/__ranges/cartesian_product_view.h
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -86,6 +86,18 @@ class cartesian_product_view : public view_interface<cartesian_product_view<Firs
constexpr explicit cartesian_product_view(First first_base, Vs... bases)
: bases_{std::move(first_base), std::move(bases)...} {}
+ constexpr iterator<false> begin()
+ requires(!__simple_view<First> || ... || !__simple_view<Vs>)
+ {
+ return iterator<false>(*this, __tuple_transform(ranges::begin, bases_));
+ }
+
+ constexpr iterator<true> begin() const
+ requires(range<const First> && ... && range<const Vs>)
+ {
+ return iterator<true>(*this, __tuple_transform(ranges::begin, bases_));
+ }
+
constexpr auto size()
requires(sized_range<First> && ... && sized_range<Vs>)
{
@@ -290,7 +302,7 @@ class cartesian_product_view<First, Vs...>::iterator {
const auto& v = std::get<N>(parent_->bases_);
auto& it = std::get<N>(current_);
const auto sz = static_cast<difference_type>(std::ranges::size(v));
- const auto first = begin(v);
+ const auto first = ranges::begin(v);
if (sz > 0) {
const auto idx = static_cast<difference_type>(std::distance(first, it));
>From 7c593fba8687787de0dbc70aa685dc62299350ef Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Sun, 20 Oct 2024 22:07:01 +0200
Subject: [PATCH 32/37] view: end()
---
.../include/__ranges/cartesian_product_view.h | 40 ++++++++++++++++++-
1 file changed, 39 insertions(+), 1 deletion(-)
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
index 39e53bffecc628..1b9b5211687d46 100644
--- a/libcxx/include/__ranges/cartesian_product_view.h
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -98,6 +98,20 @@ class cartesian_product_view : public view_interface<cartesian_product_view<Firs
return iterator<true>(*this, __tuple_transform(ranges::begin, bases_));
}
+ constexpr iterator<false> end()
+ requires((!__simple_view<First> || ... || !__simple_view<Vs>) && cartesian_product_is_common<First, Vs...>)
+ {
+ constexpr bool is_const = false;
+ return end_impl<is_const>();
+ }
+
+ constexpr iterator<true> end() const
+ requires(cartesian_product_is_common<const First, const Vs...>)
+ {
+ constexpr bool is_const = true;
+ return end_impl<is_const>();
+ }
+
constexpr auto size()
requires(sized_range<First> && ... && sized_range<Vs>)
{
@@ -111,6 +125,30 @@ class cartesian_product_view : public view_interface<cartesian_product_view<Firs
}
private:
+ template <bool is_const>
+ constexpr iterator<is_const> end_impl() const {
+ bool is_empty = end_is_empty();
+ const auto ranges_to_iterators = [is_empty, &b = bases_]<std::size_t... I>(std::index_sequence<I...>) {
+ const auto begin_or_first_end = [is_empty]<bool is_first>(const auto& rng) {
+ if constexpr (is_first)
+ return is_empty ? ranges::begin(rng) : cartesian_common_arg_end(rng);
+ return ranges::begin(rng);
+ };
+ return std::make_tuple(begin_or_first_end<I == 0>(std::get<I>(b))...);
+ };
+ iterator<is_const> it(*this, ranges_to_iterators(std::make_index_sequence<1 + sizeof...(Vs)>{}));
+ return it;
+ }
+
+ template <auto N = 0>
+ constexpr bool end_is_empty() const {
+ if constexpr (N == sizeof...(Vs))
+ return false;
+ if (const auto& v = std::get<N + 1>(bases_); ranges::empty(v))
+ return true;
+ return end_is_empty<N + 1>();
+ }
+
constexpr auto size_impl() const {
return std::apply(
[](auto&&... bases) {
@@ -332,7 +370,7 @@ class cartesian_product_view<First, Vs...>::iterator {
template <auto N = sizeof...(Vs)>
constexpr bool at_end() const {
- if (std::get<N>(current_) == end(std::get<N>(parent_->bases_)))
+ if (std::get<N>(current_) == ranges::end(std::get<N>(parent_->bases_)))
return true;
if constexpr (N > 0)
return at_end<N - 1>();
>From e1d65ac1c18fde9960eb2e27eb6c0469127ca73c Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Sun, 3 Nov 2024 12:51:39 +0100
Subject: [PATCH 33/37] view: default_sentinel_t end()
---
libcxx/include/__ranges/cartesian_product_view.h | 3 +++
1 file changed, 3 insertions(+)
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
index 1b9b5211687d46..2b9b6dca4475c7 100644
--- a/libcxx/include/__ranges/cartesian_product_view.h
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -11,6 +11,7 @@
#include <__config>
#include <__iterator/access.h> // begin
+#include <__iterator/default_sentinel.h>
#include <__iterator/distance.h>
#include <__iterator/iter_move.h>
#include <__iterator/next.h>
@@ -112,6 +113,8 @@ class cartesian_product_view : public view_interface<cartesian_product_view<Firs
return end_impl<is_const>();
}
+ constexpr default_sentinel_t end() const noexcept { return {}; }
+
constexpr auto size()
requires(sized_range<First> && ... && sized_range<Vs>)
{
>From aea6830bbac6d017b6d5cf721adf44fbdf522c69 Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Sun, 3 Nov 2024 13:02:12 +0100
Subject: [PATCH 34/37] view: clarify helper func of end()
---
libcxx/include/__ranges/cartesian_product_view.h | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
index 2b9b6dca4475c7..09b32864c88f33 100644
--- a/libcxx/include/__ranges/cartesian_product_view.h
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -143,11 +143,11 @@ class cartesian_product_view : public view_interface<cartesian_product_view<Firs
return it;
}
- template <auto N = 0>
+ template <auto N = 1>
constexpr bool end_is_empty() const {
- if constexpr (N == sizeof...(Vs))
+ if constexpr (N == 1 + sizeof...(Vs))
return false;
- if (const auto& v = std::get<N + 1>(bases_); ranges::empty(v))
+ if (const auto& v = std::get<N>(bases_); ranges::empty(v))
return true;
return end_is_empty<N + 1>();
}
>From 061e31d8c2a5af0ed89ec9f086034d039b443187 Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Sun, 3 Nov 2024 13:08:06 +0100
Subject: [PATCH 35/37] view: end(), size(): cleanup requires
---
libcxx/include/__ranges/cartesian_product_view.h | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
index 09b32864c88f33..8bd99552c9e109 100644
--- a/libcxx/include/__ranges/cartesian_product_view.h
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -107,7 +107,7 @@ class cartesian_product_view : public view_interface<cartesian_product_view<Firs
}
constexpr iterator<true> end() const
- requires(cartesian_product_is_common<const First, const Vs...>)
+ requires cartesian_product_is_common<const First, const Vs...>
{
constexpr bool is_const = true;
return end_impl<is_const>();
@@ -116,13 +116,13 @@ class cartesian_product_view : public view_interface<cartesian_product_view<Firs
constexpr default_sentinel_t end() const noexcept { return {}; }
constexpr auto size()
- requires(sized_range<First> && ... && sized_range<Vs>)
+ requires cartesian_product_is_sized<First, Vs...>
{
return size_impl();
}
constexpr auto size() const
- requires(sized_range<const First> && ... && sized_range<const Vs>)
+ requires cartesian_product_is_sized<const First, const Vs...>
{
return size_impl();
}
>From d6d6c80e1ea843d3b6b49f800f82b7948bd7ff55 Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Sun, 3 Nov 2024 13:26:40 +0100
Subject: [PATCH 36/37] iterator: iterator_concept
---
libcxx/include/__ranges/cartesian_product_view.h | 12 ++++++++++++
1 file changed, 12 insertions(+)
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
index 8bd99552c9e109..088cd869a680f6 100644
--- a/libcxx/include/__ranges/cartesian_product_view.h
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -169,8 +169,20 @@ template <input_range First, forward_range... Vs>
requires(view<First> && ... && view<Vs>)
template <bool Const>
class cartesian_product_view<First, Vs...>::iterator {
+ static constexpr auto get_iterator_tag() {
+ if constexpr (cartesian_product_is_random_access<Const, First, Vs...>)
+ return random_access_iterator_tag{};
+ else if constexpr (cartesian_product_is_bidirectional<Const, First, Vs...>)
+ return bidirectional_iterator_tag{};
+ else if constexpr (forward_range<__maybe_const<Const, First>>)
+ return forward_iterator_tag{};
+ else
+ return input_iterator_tag{};
+ }
+
public:
using iterator_category = input_iterator_tag;
+ using iterator_concept = decltype(get_iterator_tag());
using value_type = tuple<range_value_t<__maybe_const<Const, First>>, range_value_t<__maybe_const<Const, Vs>>...>;
using reference =
tuple<range_reference_t<__maybe_const<Const, First>>, range_reference_t<__maybe_const<Const, Vs>>...>;
>From b16e6032a53af7869771257f70ed38217907e667 Mon Sep 17 00:00:00 2001
From: Paul <paulxicao7 at gmail.com>
Date: Sun, 3 Nov 2024 21:46:05 +0100
Subject: [PATCH 37/37] iterator: multiple smaller fixes/cleanups
---
.../include/__ranges/cartesian_product_view.h | 41 +++++++++----------
1 file changed, 20 insertions(+), 21 deletions(-)
diff --git a/libcxx/include/__ranges/cartesian_product_view.h b/libcxx/include/__ranges/cartesian_product_view.h
index 088cd869a680f6..79e7cff84d4cdf 100644
--- a/libcxx/include/__ranges/cartesian_product_view.h
+++ b/libcxx/include/__ranges/cartesian_product_view.h
@@ -193,7 +193,7 @@ class cartesian_product_view<First, Vs...>::iterator {
constexpr iterator(iterator<!Const> i)
requires Const && (convertible_to<iterator_t<First>, iterator_t<const First>> && ... &&
convertible_to<iterator_t<Vs>, iterator_t<const Vs>>)
- : parent_(std::addressof(i.parent_)), current_(std::move(i.current_)) {}
+ : parent_(i.parent_), current_(std::move(i.current_)) {}
constexpr auto operator*() const {
return __tuple_transform([](auto& i) -> decltype(auto) { return *i; }, current_);
@@ -204,13 +204,13 @@ class cartesian_product_view<First, Vs...>::iterator {
return *this;
}
- constexpr void operator++(int) { next(); }
+ constexpr void operator++(int) { ++*this; }
constexpr iterator operator++(int)
requires forward_range<__maybe_const<Const, First>>
{
auto tmp = *this;
- next();
+ ++*this;
return tmp;
}
@@ -225,7 +225,7 @@ class cartesian_product_view<First, Vs...>::iterator {
requires cartesian_product_is_bidirectional<Const, First, Vs...>
{
auto tmp = *this;
- prev();
+ --*this;
return tmp;
}
@@ -281,8 +281,8 @@ class cartesian_product_view<First, Vs...>::iterator {
return iterator(x) -= y;
}
- friend constexpr iterator operator-(const iterator& x, const iterator& y)
- requires cartesian_product_is_random_access<Const, First, Vs...>
+ friend constexpr difference_type operator-(const iterator& x, const iterator& y)
+ requires cartesian_is_sized_sentinel<Const, iterator_t, First, Vs...>
{
return x.distance_from(y.current_);
}
@@ -290,10 +290,9 @@ class cartesian_product_view<First, Vs...>::iterator {
friend constexpr difference_type operator-(const iterator& i, default_sentinel_t)
requires cartesian_is_sized_sentinel<Const, sentinel_t, First, Vs...>
{
- MultiIterator end_tuple;
- std::get<0>(end_tuple) = ranges::end(std::get<0>(i.parent_->bases_));
- for (int N = 1; N <= sizeof...(Vs); N++)
- std::get<N>(end_tuple) = ranges::begin(std::get<N>(i.parent_->bases_));
+ tuple end_tuple = [&b = i.parent_->bases_]<size_t... I>(index_sequence<I...>) {
+ return tuple{ranges::end(std::get<0>(b)), ranges::begin(std::get<1 + I>(b))...};
+ }(std::make_index_sequence<sizeof...(Vs)>{});
return i.distance_from(end_tuple);
}
@@ -311,19 +310,16 @@ class cartesian_product_view<First, Vs...>::iterator {
requires(indirectly_swappable<iterator_t<__maybe_const<Const, First>>> && ... &&
indirectly_swappable<iterator_t<__maybe_const<Const, Vs>>>)
{
- iter_swap_helper(l, r);
+ iter_swap_impl(l, r);
}
private:
- using Parent = __maybe_const<Const, cartesian_product_view>;
- Parent* parent_ = nullptr;
+ using Parent = __maybe_const<Const, cartesian_product_view>;
+ Parent* parent_ = nullptr;
using MultiIterator = tuple<iterator_t<__maybe_const<Const, First>>, iterator_t<__maybe_const<Const, Vs>>...>;
MultiIterator current_;
- constexpr iterator(Parent& parent, decltype(current_) current)
- : parent_(std::addressof(parent)), current_(std::move(current)) {}
-
- template <auto N = sizeof...(Vs)>
+ template <size_t N = sizeof...(Vs)>
constexpr void next() {
auto& it = std::get<N>(current_);
++it;
@@ -335,7 +331,7 @@ class cartesian_product_view<First, Vs...>::iterator {
}
}
- template <auto N = sizeof...(Vs)>
+ template <size_t N = sizeof...(Vs)>
constexpr void prev() {
auto& it = std::get<N>(current_);
if constexpr (N > 0) {
@@ -347,7 +343,7 @@ class cartesian_product_view<First, Vs...>::iterator {
--it;
}
- template <std::size_t N = sizeof...(Vs)>
+ template <auto N = sizeof...(Vs)>
constexpr void advance(difference_type x) {
if (x == 0)
return;
@@ -416,11 +412,14 @@ class cartesian_product_view<First, Vs...>::iterator {
return static_cast<difference_type>(0);
}
+ constexpr iterator(Parent& parent, MultiIterator current)
+ : parent_(std::addressof(parent)), current_(std::move(current)) {}
+
template <auto N = sizeof...(Vs)>
- static constexpr void iter_swap_helper(const iterator& l, const iterator& r) {
+ static constexpr void iter_swap_impl(const iterator& l, const iterator& r) {
ranges::iter_swap(std::get<N>(l.current_), std::get<N>(r.current_));
if constexpr (N > 0)
- iter_swap_helper<N - 1>(l, r);
+ iter_swap_impl<N - 1>(l, r);
}
};
More information about the libcxx-commits
mailing list