> The bit I haven't quite grasped is the circumstances under which \$pos1 and \$pos2 should be considered the same.

Never, it's a false positive.

(Or to be more precise only if both are aliases, hence \$pos1 == \$pos2 , but which can't happen in my use case )

They are not nested in the OP because it's the easiest possible demo.

See here Re: Test scalar refs (not values) in deeply nested structure (workaround) for more test cases.

Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery

In reply to Re^2: Test scalar refs (not values) in deeply nested structure by LanX
in thread Test scalar refs (not values) in deeply nested structure by LanX

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