[clang-tools-extra] [clang-tidy] Support C++26 placeholder bindings (PR #207604)

[Baranov Victor via cfe-commits]

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vbvictor wrote:

BTW, I think we can allow contributors to write RST till official 24th release (in winter). Or till we migrate all current documentation.


https://github.com/llvm/llvm-project/pull/207604