[clang] [clang-tools-extra] [libcxx] [llvm] [libc++] implement views::concat (PR #120920)

[Nhat Nguyen via llvm-commits]

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@@ -0,0 +1,54 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
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changkhothuychung wrote:

Hi, can you elaborate a bit more, what do I need to change in these test files? 

https://github.com/llvm/llvm-project/pull/120920