[libcxx-commits] [libcxx] [libc++][ranges] implement `std::ranges::zip_transform_view` (PR #79605)

[Louis Dionne via libcxx-commits]

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@@ -0,0 +1,72 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+
+// constexpr auto begin();
+// constexpr auto begin() const
+//   requires range<const InnerView> &&
+//            regular_invocable<const F&, range_reference_t<const Views>...>;
+
+#include <ranges>
+
+#include <cassert>
+#include <concepts>
+
+#include "types.h"
+
+template <class T>
+concept HasConstBegin = requires(const T& ct) { ct.begin(); };
+
+template <class T>
+concept HasBegin = requires(T& t) { t.begin(); };
+
+constexpr bool test() {
+  int buffer[8] = {1, 2, 3, 4, 5, 6, 7, 8};
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ldionne wrote:

I'd like to have an actual runtime test for 1, 2 and 3 views.

Also, a test where you put an empty view in position 0, 1 and 2.

https://github.com/llvm/llvm-project/pull/79605