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

[Louis Dionne via libcxx-commits]

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@@ -0,0 +1,500 @@
+//===----------------------------------------------------------------------===//
+//
+// 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 TEST_STD_RANGES_RANGE_ADAPTORS_RANGE_ZIP_TRANSFORM_TYPES_H
+#define TEST_STD_RANGES_RANGE_ADAPTORS_RANGE_ZIP_TRANSFORM_TYPES_H
+
+#include <functional>
+#include <ranges>
+
+#include "test_macros.h"
+#include "test_iterators.h"
+#include "test_range.h"
+
+#if TEST_STD_VER <= 20
+#  error "range.zip.transform/types.h" can only be included in builds supporting C++20
+#endif // TEST_STD_VER <= 20
+
+struct IntView : std::ranges::view_base {
+  int* begin() const;
+  int* end() const;
+};
+
+struct Fn {
+  int operator()(auto&&...) const { return 5; }
+};
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ldionne wrote:

IMO this is small enough that we should define it in each TU where it's used. Otherwise it's less readable to have to jump around just to see this simple definition.

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