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

[Erich Keane via cfe-commits]

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@@ -1884,6 +1884,10 @@ class Parser : public CodeCompletionHandler {
   // C++ Expressions
   ExprResult tryParseCXXIdExpression(CXXScopeSpec &SS, bool isAddressOfOperand,
                                      Token &Replacement);
+
+  ExprResult tryParseCXXPackIndexingExpression(ExprResult PackIdExpression);
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erichkeane wrote:

Some detailed comments on what the difference between teh expression/indexed type name pack parsing would be nice/helpful.

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