The cryptic comment in perlref that you refer to is this behaviour: 
$foo{bar}{baz}; # Assumes $foo{bar} exists and is a hash
print ref($foo{bar}); # And lo and behold, it is!

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And I am with japhy on not knowing why this works. Certainly there is nothing I know of about context that would explain it...

In reply to Re (tilly) 4: Warnings, and declaring Hashes of Hashes. by tilly
in thread Warnings, and declaring Hashes of Hashes. by BatGnat

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