[Mlir-commits] [llvm] [mlir] [ADT] Use a dedicated empty type for StringSet (NFC) (PR #165967)

[Jakub Kuderski]

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@@ -21,6 +21,9 @@
 
 namespace llvm {
 
+/// The "value type" of StringSet represented as an empty struct.
+struct StringSetTag {};
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kuhar wrote:

If this is only meant for the empty state, maybe call it `EnptyStringSetTag`? Unless I misunderstood this.

https://github.com/llvm/llvm-project/pull/165967