# reading from file
# flintstones: lead=fred pal=barney wife=wilma pet=dino
while ( <> ) {
    next unless s/^(.*?):\s*//;
    $who = $1;
    for $field ( split ) {
        ($key, $value) = split /=/, $field;
        $HoH{$who}{$key} = $value;
    }
}

# reading from file; more temporary variables
while ( <> ) {
    next unless s/^(.*?):\s*//;
    $who = $1;
    $rec = {};
    $HoH{$who} = $rec;
    for $field ( split ) {
        ($key, $value) = split /=/, $field;
        $rec->{$key} = $value;
    }
}

# calling a function that returns a key,value for the inner hash
for $group ( "simpsons", "jetsons", "flintstones" ) {
    $HoH{$group} = { get_family($group) };
}

# likewise, but using temporary variables
for $group ( "simpsons", "jetsons", "flintstones" ) {
    %members = get_family($group);
    $HoH{$group} = { %members };
}

# calling a function that returns the outer hash, including
# references to the created inner hashes
sub hash_families {
    my @ret;
    foreach $group ( @_ ) {
        push @ret, $group, { get_family($group) };
    }
    @ret;
}
%HoH = hash_families( "simpsons", "jetsons", "flintstones" );

# append new members to an existing family
%new_folks = (
    wife => "wilma",
    pet  => "dino";
);
for $what (keys %new_folks) {
    $HoH{flintstones}{$what} = $new_folks{$what};
}