It's effectively identical to %foo = ( {} => undef );.

If strict/warnings were in force, it would have il elicited: 

%foo = {};;
Reference found where even-sized list expected at ...

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Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
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In reply to Re: Curious about Hashes which viewed as a list has only one item by BrowserUk
in thread Curious about Hashes which viewed as a list has only one item by ack

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