DB<33> $h{!A}=1

  DB<34> $h{!(A)}=1

  DB<35> $h{!("A")}=1

  DB<36> x \%h
0  HASH(0x32dad38)
   '' => 1
  DB<37>

##</code><code>##

  DB<40> @h!{"A"} = (1)
syntax error at ...