And in object-speak, one seldom uses $object += ..., as theat requires complicated overloading.

my $pan = Saucepan->new ();
$pan->heat ("medium");
$pan->add (Ingredient->new ("butter", cup => .5));
$pan->add (Ingredient->new ("sugar",  cup => .5));
wait () until $pan->content ()->state ("melted");
$pan->bubble ($_) for Time->new (minute => (1 || 2));
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