my $array=[]; #$array is a refrence to an anonymous array my @array; #### $array[1]; #### $array->[1]; #### my @sorted=map {$_->[0]} sort{$a->[1] <=> $b->[1]} map {[$_,keyfunction($_)]} @list; my $nasty=join(",", map {$_->[0]} sort{$a->[1] <=> $b->[1]} map {[$_,keyfunction($_)]} grep {/^\w/} @list );