Select Code to Download

my @cards = (
    {
...
        cost=>{ air=>2, electricity=>4 },
    },
);

my @players = (
    {
...
        mana =>{ water=>5, frost=>10 },
    },
);

sub can_cast {
    my ($rPlayer, $rCard) = @_;
...
    # Nothing rejected, so we can cast it!
    return 1;
}

$ cat mana.pl
use strict;
...
$ perl mana.pl
Joe can cast: Fireball Lightning bolt
Audrey can cast: Ice wall