Hello monks, could you please help me understand this syntax? Why do we have parentheses around FOO/BAR in the hash? Thanks a bunch!

use constant FOO => 10;
use constant BAR => 20; 

%BAZ = ( FOO() => 1, 
         BAR() => 1
 );

sub is_baz {
    my $i = shift; 
    return ( exists $BAZ{$i} ) ? 1 : 0;
}
....
is_baz(10);

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In reply to understanding this syntax by Anonymous Monk

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