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

[Christopher Di Bella via cfe-commits]

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@@ -0,0 +1,202 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
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cjdb wrote:

Ah, this comment was made before my revert, so it's no longer applicable.

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