The output of Data::Dumper is misleading here, as it looks like undef was assigned to the value, not the key. But it's the key that gets the scalar: 
qwurx [shmem] ~ > perl -le '%h = "one"; print "$_ => $h{$_}" for keys 
+%h'
one =>

[download]

--shmem 

_($_=" "x(1<<5)."?\n".q·/)Oo.  G°\        /
                              /\_¯/(q    /
----------------------------  \__(m.====·.(_("always off the crowd"))."·
");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}

In reply to Re^2: hash assignment wierdness by shmem
in thread hash assignment wierdness by Bro. Doug

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