use Data::Dumper;

my %h = 'a'..'f';
$_ .= '_mod' for %h;

print Dumper \%h;

##</code><code>##

$h{a_mod} = delete $h{a};

##</code><code>##

my @h = 'a'..'f';
$_ .= '_mod' for @h;

%h = @h;
print Dumper \%h;