[clang] [Clang][C++26] Implement Pack Indexing (P2662R3). (PR #72644)

[Erich Keane via cfe-commits]

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@@ -309,6 +309,7 @@ class DeclSpec {
   static const TST TST_typeof_unqualExpr = clang::TST_typeof_unqualExpr;
   static const TST TST_decltype = clang::TST_decltype;
   static const TST TST_decltype_auto = clang::TST_decltype_auto;
+  static const TST TST_indexed_typename_pack = clang::TST_indexed_typename_pack;
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erichkeane wrote:

another place where we're using 'indexed pack' instead of 'pack indexing'?  

https://github.com/llvm/llvm-project/pull/72644