[libcxx-commits] [libcxx] [libc++] Introduce `__product_iterator_traits` and optimise `flat_map::insert` (PR #139454)

[Louis Dionne via libcxx-commits]

================
@@ -93,6 +94,25 @@ struct __flat_map_utils {
     }
     return __num_appended;
   }
+
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ldionne wrote:

The `TODO` above can now go away.

https://github.com/llvm/llvm-project/pull/139454