a.b cannot be auto-stringified because it does not match the pattern ^\w+$. What you're observing is the valid perl a.b becomng 'a'.'b' because strict allowed your bareword strings to be unquoted. At this point this has nothing to do with being a hash key. It's just that they're an expression. Enable strict to see what you were missing.

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In reply to Re^4: Numeric as hash key returns undef... by diotalevi
in thread Numeric as hash key returns undef... by journey

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