package Qty;
sub new {
    my $class = shift;
    bless { @_ }, $class;
}
sub qtyTotal {
    my $phObj = shift;
    foreach my $qType ('qty', 'qtySum', 'qtyCont'){
        $qty += $phObj->{$qType} if exists $phObj->{$qType};
    }
    return $qty;
}

package main;

my %phrases = (
 "phrase 1" => Qty->new(
   qty        => 1,
   qtySum     => 5,
   qtyCont    => 8,
 ),
 "phrase 2" => Qty->new(
   qty        =>10,
   qtyCont    =>34,
 ),
 "phrase 3" => Qty->new(
   qty        =>1,
 ),
);

print "${ \$phrases{'phrase 2'}->qtyTotal() }\n";