~ $ perl -de0

...


  DB<4> $hash{key1} = 'val1'  # add scalar to %hash

  DB<5> say %hash             # list form
key1val1

  DB<6> x \%hash              # dump
0  HASH(0xb400007063b64e70)
   'key1' => 'val1'
  DB<7> use strict; $hash{key1} = 'val1'
Variable "%hash" is not imported at...

# versa

DB<8> $hash->{key2} = 'val2'     # add scalar to $hash

  DB<9> say $hash                # hash ref
HASH(0xb400007063ceb198)

  DB<10> x $hash                 # dump
0  HASH(0xb400007063ceb198)
   'key2' => 'val2'
  DB<11> use strict; $hash->{key2} = 'val2'
Variable "$hash" is not imported at