c:\@Work\Perl\monks>perl -wMstrict -MData::Dump -le "my %h; ;; $h{'www'}{'xxx'}{'yyy'}{'zzz'}; dd 'access in void context', \%h; %h = (); dd 'assigning empty list really does clear hash', \%h; ;; my $x = $h{'www'}{'xxx'}{'yyy'}{'zzz'}; dd 'access in assignment (rvalue) context', \%h; %h = (); ;; 1 if $h{'www'}{'xxx'}{'yyy'}{'zzz'}; dd 'access in boolean context', \%h; %h = (); ;; 1 for $h{'www'}{'xxx'}{'yyy'}{'zzz'}; dd 'access in aliased (lvalue) context', \%h; " Useless use of hash element in void context at -e line 1. ("access in void context", { www => { xxx => { yyy => {} } } }) ("assigning empty list really does clear hash", {}) ( "access in assignment (rvalue) context", { www => { xxx => { yyy => {} } } }, ) ( "access in boolean context", { www => { xxx => { yyy => {} } } }, ) ( "access in aliased (lvalue) context", { www => { xxx => { yyy => { zzz => undef } } } }, )