$ perl -e '$h={a=>2,b=>3,c=>4};print %$h'
    a2b3c4

    $ perl -e '$h={a=>2,b=>3,c=>4};print @$h'
    Not an ARRAY reference at -e line 1.
 
    $ perl -e '%h=(a=>2,b=>3,c=>4);@a=%h;print@a'
    a2b3c4