Generation of a HASH OF LISTS

 # reading from file
 # flintstones: fred barney wilma dino
 while ( <> ) {
     next unless s/^(.*?):\s*//;
     $HoL{$1} = [ split ];
 }

 # reading from file; more temps
 # flintstones: fred barney wilma dino
 while ( $line = <> ) {
     ($who, $rest) = split /:\s*/, $line, 2;
     @fields = split ' ', $rest;
     $HoL{$who} = [ @fields ];
 }

 # calling a function that returns a list
 for $group ( "simpsons", "jetsons", "flintstones" ) {
     $HoL{$group} = [ get_family($group) ];
 }

 # likewise, but using temps
 for $group ( "simpsons", "jetsons", "flintstones" ) {
     @members = get_family($group);
     $HoL{$group} = [ @members ];
 }

 # append new members to an existing family
 push @{ $HoL{"flintstones"} }, "wilma", "betty";