This module works: after a tieing a hash, you get elements back in the order they were inserted. Tie::InsertOrderHash has a slightly nicer interface, where the contents of a hash can be assigned in the tie statement.
The documentation would be much better if it explained what this module does on its own terms, rather than describing itself relative to Tie::IxHash, which the reader may not be familiar with.
I'm not convinced about the name: to me "indexed" makes me think more of being able to access hash elements by number; I'd simply describe a hash of the type this module provides as being "ordered".
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