[llvm] [libcxx] [clang-tools-extra] [clang] [libcxx] adds ranges::fold_left_with_iter and ranges::fold_left (PR #75259)

[Konstantin Varlamov via cfe-commits]

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@@ -0,0 +1,259 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+// <algorithm>
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// Checks that `std::ranges::fold_left_with_iter`'s requirements reject parameters that don't meet
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var-const wrote:

Nit: this comment should also mention `fold_left`.

Consider also copying the declaration of the algorithms into the comment, so that the exact requirements are easy to see.

https://github.com/llvm/llvm-project/pull/75259